rpc/generator: try to resolve return types too

Godeps/Godeps.json

@@ -118,6 +118,22 @@
 			"ImportPath": "golang.org/x/tools/go/ast/astutil",
 			"Rev": "69f53eb622e0f41d0e91debd71d6694148b52a30"
 		},
+		{
+			"ImportPath": "golang.org/x/tools/go/buildutil",
+			"Rev": "69f53eb622e0f41d0e91debd71d6694148b52a30"
+		},
+		{
+			"ImportPath": "golang.org/x/tools/go/exact",
+			"Rev": "69f53eb622e0f41d0e91debd71d6694148b52a30"
+		},
+		{
+			"ImportPath": "golang.org/x/tools/go/loader",
+			"Rev": "69f53eb622e0f41d0e91debd71d6694148b52a30"
+		},
+		{
+			"ImportPath": "golang.org/x/tools/go/types",
+			"Rev": "69f53eb622e0f41d0e91debd71d6694148b52a30"
+		},
 		{
 			"ImportPath": "golang.org/x/tools/imports",
 			"Rev": "69f53eb622e0f41d0e91debd71d6694148b52a30"

Godeps/_workspace/src/golang.org/x/tools/go/buildutil/allpackages.go

@@ -0,0 +1,123 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package buildutil provides utilities related to the go/build
+// package in the standard library.
+//
+// All I/O is done via the build.Context file system interface, which must
+// be concurrency-safe.
+package buildutil
+
+import (
+	"go/build"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"sync"
+)
+
+// AllPackages returns the import path of each Go package in any source
+// directory of the specified build context (e.g. $GOROOT or an element
+// of $GOPATH).  Errors are ignored.  The results are sorted.
+//
+// The result may include import paths for directories that contain no
+// *.go files, such as "archive" (in $GOROOT/src).
+//
+// All I/O is done via the build.Context file system interface,
+// which must be concurrency-safe.
+//
+func AllPackages(ctxt *build.Context) []string {
+	var list []string
+	ForEachPackage(ctxt, func(pkg string, _ error) {
+		list = append(list, pkg)
+	})
+	sort.Strings(list)
+	return list
+}
+
+// ForEachPackage calls the found function with the import path of
+// each Go package it finds in any source directory of the specified
+// build context (e.g. $GOROOT or an element of $GOPATH).
+//
+// If the package directory exists but could not be read, the second
+// argument to the found function provides the error.
+//
+// All I/O is done via the build.Context file system interface,
+// which must be concurrency-safe.
+//
+func ForEachPackage(ctxt *build.Context, found func(importPath string, err error)) {
+	// We use a counting semaphore to limit
+	// the number of parallel calls to ReadDir.
+	sema := make(chan bool, 20)
+
+	ch := make(chan item)
+
+	var wg sync.WaitGroup
+	for _, root := range ctxt.SrcDirs() {
+		root := root
+		wg.Add(1)
+		go func() {
+			allPackages(ctxt, sema, root, ch)
+			wg.Done()
+		}()
+	}
+	go func() {
+		wg.Wait()
+		close(ch)
+	}()
+
+	// All calls to found occur in the caller's goroutine.
+	for i := range ch {
+		found(i.importPath, i.err)
+	}
+}
+
+type item struct {
+	importPath string
+	err        error // (optional)
+}
+
+func allPackages(ctxt *build.Context, sema chan bool, root string, ch chan<- item) {
+	root = filepath.Clean(root) + string(os.PathSeparator)
+
+	var wg sync.WaitGroup
+
+	var walkDir func(dir string)
+	walkDir = func(dir string) {
+		// Avoid .foo, _foo, and testdata directory trees.
+		base := filepath.Base(dir)
+		if base == "" || base[0] == '.' || base[0] == '_' || base == "testdata" {
+			return
+		}
+
+		pkg := filepath.ToSlash(strings.TrimPrefix(dir, root))
+
+		// Prune search if we encounter any of these import paths.
+		switch pkg {
+		case "builtin":
+			return
+		}
+
+		sema <- true
+		files, err := ReadDir(ctxt, dir)
+		<-sema
+		if pkg != "" || err != nil {
+			ch <- item{pkg, err}
+		}
+		for _, fi := range files {
+			fi := fi
+			if fi.IsDir() {
+				wg.Add(1)
+				go func() {
+					walkDir(filepath.Join(dir, fi.Name()))
+					wg.Done()
+				}()
+			}
+		}
+	}
+
+	walkDir(root)
+	wg.Wait()
+}

Godeps/_workspace/src/golang.org/x/tools/go/buildutil/allpackages_test.go

@@ -0,0 +1,32 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package buildutil_test
+
+import (
+	"go/build"
+	"testing"
+
+	"golang.org/x/tools/go/buildutil"
+)
+
+func TestAllPackages(t *testing.T) {
+	all := buildutil.AllPackages(&build.Default)
+
+	set := make(map[string]bool)
+	for _, pkg := range all {
+		set[pkg] = true
+	}
+
+	const wantAtLeast = 250
+	if len(all) < wantAtLeast {
+		t.Errorf("Found only %d packages, want at least %d", len(all), wantAtLeast)
+	}
+
+	for _, want := range []string{"fmt", "crypto/sha256", "golang.org/x/tools/go/buildutil"} {
+		if !set[want] {
+			t.Errorf("Package %q not found; got %s", want, all)
+		}
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/buildutil/fakecontext.go

@@ -0,0 +1,108 @@
+package buildutil
+
+import (
+	"fmt"
+	"go/build"
+	"io"
+	"io/ioutil"
+	"os"
+	"path"
+	"path/filepath"
+	"sort"
+	"strings"
+	"time"
+)
+
+// FakeContext returns a build.Context for the fake file tree specified
+// by pkgs, which maps package import paths to a mapping from file base
+// names to contents.
+//
+// The fake Context has a GOROOT of "/go" and no GOPATH, and overrides
+// the necessary file access methods to read from memory instead of the
+// real file system.
+//
+// Unlike a real file tree, the fake one has only two levels---packages
+// and files---so ReadDir("/go/src/") returns all packages under
+// /go/src/ including, for instance, "math" and "math/big".
+// ReadDir("/go/src/math/big") would return all the files in the
+// "math/big" package.
+//
+func FakeContext(pkgs map[string]map[string]string) *build.Context {
+	clean := func(filename string) string {
+		f := path.Clean(filepath.ToSlash(filename))
+		// Removing "/go/src" while respecting segment
+		// boundaries has this unfortunate corner case:
+		if f == "/go/src" {
+			return ""
+		}
+		return strings.TrimPrefix(f, "/go/src/")
+	}
+
+	ctxt := build.Default // copy
+	ctxt.GOROOT = "/go"
+	ctxt.GOPATH = ""
+	ctxt.IsDir = func(dir string) bool {
+		dir = clean(dir)
+		if dir == "" {
+			return true // needed by (*build.Context).SrcDirs
+		}
+		return pkgs[dir] != nil
+	}
+	ctxt.ReadDir = func(dir string) ([]os.FileInfo, error) {
+		dir = clean(dir)
+		var fis []os.FileInfo
+		if dir == "" {
+			// enumerate packages
+			for importPath := range pkgs {
+				fis = append(fis, fakeDirInfo(importPath))
+			}
+		} else {
+			// enumerate files of package
+			for basename := range pkgs[dir] {
+				fis = append(fis, fakeFileInfo(basename))
+			}
+		}
+		sort.Sort(byName(fis))
+		return fis, nil
+	}
+	ctxt.OpenFile = func(filename string) (io.ReadCloser, error) {
+		filename = clean(filename)
+		dir, base := path.Split(filename)
+		content, ok := pkgs[path.Clean(dir)][base]
+		if !ok {
+			return nil, fmt.Errorf("file not found: %s", filename)
+		}
+		return ioutil.NopCloser(strings.NewReader(content)), nil
+	}
+	ctxt.IsAbsPath = func(path string) bool {
+		path = filepath.ToSlash(path)
+		// Don't rely on the default (filepath.Path) since on
+		// Windows, it reports virtual paths as non-absolute.
+		return strings.HasPrefix(path, "/")
+	}
+	return &ctxt
+}
+
+type byName []os.FileInfo
+
+func (s byName) Len() int           { return len(s) }
+func (s byName) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+func (s byName) Less(i, j int) bool { return s[i].Name() < s[j].Name() }
+
+type fakeFileInfo string
+
+func (fi fakeFileInfo) Name() string    { return string(fi) }
+func (fakeFileInfo) Sys() interface{}   { return nil }
+func (fakeFileInfo) ModTime() time.Time { return time.Time{} }
+func (fakeFileInfo) IsDir() bool        { return false }
+func (fakeFileInfo) Size() int64        { return 0 }
+func (fakeFileInfo) Mode() os.FileMode  { return 0644 }
+
+type fakeDirInfo string
+
+func (fd fakeDirInfo) Name() string    { return string(fd) }
+func (fakeDirInfo) Sys() interface{}   { return nil }
+func (fakeDirInfo) ModTime() time.Time { return time.Time{} }
+func (fakeDirInfo) IsDir() bool        { return true }
+func (fakeDirInfo) Size() int64        { return 0 }
+func (fakeDirInfo) Mode() os.FileMode  { return 0755 }

Godeps/_workspace/src/golang.org/x/tools/go/buildutil/tags.go

@@ -0,0 +1,73 @@
+package buildutil
+
+// This logic was copied from stringsFlag from $GOROOT/src/cmd/go/build.go.
+
+import "fmt"
+
+const TagsFlagDoc = "a list of `build tags` to consider satisfied during the build. " +
+	"For more information about build tags, see the description of " +
+	"build constraints in the documentation for the go/build package"
+
+// TagsFlag is an implementation of the flag.Value interface that parses
+// a flag value in the same manner as go build's -tags flag and
+// populates a []string slice.
+//
+// See $GOROOT/src/go/build/doc.go for description of build tags.
+// See $GOROOT/src/cmd/go/doc.go for description of 'go build -tags' flag.
+//
+// Example:
+//	flag.Var((*buildutil.TagsFlag)(&build.Default.BuildTags), "tags", buildutil.TagsDoc)
+type TagsFlag []string
+
+func (v *TagsFlag) Set(s string) error {
+	var err error
+	*v, err = splitQuotedFields(s)
+	if *v == nil {
+		*v = []string{}
+	}
+	return err
+}
+
+func splitQuotedFields(s string) ([]string, error) {
+	// Split fields allowing '' or "" around elements.
+	// Quotes further inside the string do not count.
+	var f []string
+	for len(s) > 0 {
+		for len(s) > 0 && isSpaceByte(s[0]) {
+			s = s[1:]
+		}
+		if len(s) == 0 {
+			break
+		}
+		// Accepted quoted string. No unescaping inside.
+		if s[0] == '"' || s[0] == '\'' {
+			quote := s[0]
+			s = s[1:]
+			i := 0
+			for i < len(s) && s[i] != quote {
+				i++
+			}
+			if i >= len(s) {
+				return nil, fmt.Errorf("unterminated %c string", quote)
+			}
+			f = append(f, s[:i])
+			s = s[i+1:]
+			continue
+		}
+		i := 0
+		for i < len(s) && !isSpaceByte(s[i]) {
+			i++
+		}
+		f = append(f, s[:i])
+		s = s[i:]
+	}
+	return f, nil
+}
+
+func (v *TagsFlag) String() string {
+	return "<tagsFlag>"
+}
+
+func isSpaceByte(c byte) bool {
+	return c == ' ' || c == '\t' || c == '\n' || c == '\r'
+}

Godeps/_workspace/src/golang.org/x/tools/go/buildutil/tags_test.go

@@ -0,0 +1,28 @@
+package buildutil_test
+
+import (
+	"flag"
+	"go/build"
+	"reflect"
+	"testing"
+
+	"golang.org/x/tools/go/buildutil"
+)
+
+func TestTags(t *testing.T) {
+	f := flag.NewFlagSet("TestTags", flag.PanicOnError)
+	var ctxt build.Context
+	f.Var((*buildutil.TagsFlag)(&ctxt.BuildTags), "tags", buildutil.TagsFlagDoc)
+	f.Parse([]string{"-tags", ` 'one'"two"	'three "four"'`, "rest"})
+
+	// BuildTags
+	want := []string{"one", "two", "three \"four\""}
+	if !reflect.DeepEqual(ctxt.BuildTags, want) {
+		t.Errorf("BuildTags = %q, want %q", ctxt.BuildTags, want)
+	}
+
+	// Args()
+	if want := []string{"rest"}; !reflect.DeepEqual(f.Args(), want) {
+		t.Errorf("f.Args() = %q, want %q", f.Args(), want)
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/buildutil/util.go

@@ -0,0 +1,158 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package buildutil
+
+import (
+	"fmt"
+	"go/ast"
+	"go/build"
+	"go/parser"
+	"go/token"
+	"io"
+	"io/ioutil"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+)
+
+// ParseFile behaves like parser.ParseFile,
+// but uses the build context's file system interface, if any.
+//
+// If file is not absolute (as defined by IsAbsPath), the (dir, file)
+// components are joined using JoinPath; dir must be absolute.
+//
+// The displayPath function, if provided, is used to transform the
+// filename that will be attached to the ASTs.
+//
+// TODO(adonovan): call this from go/loader.parseFiles when the tree thaws.
+//
+func ParseFile(fset *token.FileSet, ctxt *build.Context, displayPath func(string) string, dir string, file string, mode parser.Mode) (*ast.File, error) {
+	if !IsAbsPath(ctxt, file) {
+		file = JoinPath(ctxt, dir, file)
+	}
+	rd, err := OpenFile(ctxt, file)
+	if err != nil {
+		return nil, err
+	}
+	defer rd.Close() // ignore error
+	if displayPath != nil {
+		file = displayPath(file)
+	}
+	return parser.ParseFile(fset, file, rd, mode)
+}
+
+// ContainingPackage returns the package containing filename.
+//
+// If filename is not absolute, it is interpreted relative to working directory dir.
+// All I/O is via the build context's file system interface, if any.
+//
+// The '...Files []string' fields of the resulting build.Package are not
+// populated (build.FindOnly mode).
+//
+// TODO(adonovan): call this from oracle when the tree thaws.
+//
+func ContainingPackage(ctxt *build.Context, dir, filename string) (*build.Package, error) {
+	if !IsAbsPath(ctxt, filename) {
+		filename = JoinPath(ctxt, dir, filename)
+	}
+
+	// We must not assume the file tree uses
+	// "/" always,
+	// `\` always,
+	// or os.PathSeparator (which varies by platform),
+	// but to make any progress, we are forced to assume that
+	// paths will not use `\` unless the PathSeparator
+	// is also `\`, thus we can rely on filepath.ToSlash for some sanity.
+
+	dirSlash := path.Dir(filepath.ToSlash(filename)) + "/"
+
+	// We assume that no source root (GOPATH[i] or GOROOT) contains any other.
+	for _, srcdir := range ctxt.SrcDirs() {
+		srcdirSlash := filepath.ToSlash(srcdir) + "/"
+		if strings.HasPrefix(dirSlash, srcdirSlash) {
+			importPath := dirSlash[len(srcdirSlash) : len(dirSlash)-len("/")]
+			return ctxt.Import(importPath, dir, build.FindOnly)
+		}
+	}
+
+	return nil, fmt.Errorf("can't find package containing %s", filename)
+}
+
+// -- Effective methods of file system interface -------------------------
+
+// (go/build.Context defines these as methods, but does not export them.)
+
+// TODO(adonovan): HasSubdir?
+
+// FileExists returns true if the specified file exists,
+// using the build context's file system interface.
+func FileExists(ctxt *build.Context, path string) bool {
+	if ctxt.OpenFile != nil {
+		r, err := ctxt.OpenFile(path)
+		if err != nil {
+			return false
+		}
+		r.Close() // ignore error
+		return true
+	}
+	_, err := os.Stat(path)
+	return err == nil
+}
+
+// OpenFile behaves like os.Open,
+// but uses the build context's file system interface, if any.
+func OpenFile(ctxt *build.Context, path string) (io.ReadCloser, error) {
+	if ctxt.OpenFile != nil {
+		return ctxt.OpenFile(path)
+	}
+	return os.Open(path)
+}
+
+// IsAbsPath behaves like filepath.IsAbs,
+// but uses the build context's file system interface, if any.
+func IsAbsPath(ctxt *build.Context, path string) bool {
+	if ctxt.IsAbsPath != nil {
+		return ctxt.IsAbsPath(path)
+	}
+	return filepath.IsAbs(path)
+}
+
+// JoinPath behaves like filepath.Join,
+// but uses the build context's file system interface, if any.
+func JoinPath(ctxt *build.Context, path ...string) string {
+	if ctxt.JoinPath != nil {
+		return ctxt.JoinPath(path...)
+	}
+	return filepath.Join(path...)
+}
+
+// IsDir behaves like os.Stat plus IsDir,
+// but uses the build context's file system interface, if any.
+func IsDir(ctxt *build.Context, path string) bool {
+	if ctxt.IsDir != nil {
+		return ctxt.IsDir(path)
+	}
+	fi, err := os.Stat(path)
+	return err == nil && fi.IsDir()
+}
+
+// ReadDir behaves like ioutil.ReadDir,
+// but uses the build context's file system interface, if any.
+func ReadDir(ctxt *build.Context, path string) ([]os.FileInfo, error) {
+	if ctxt.ReadDir != nil {
+		return ctxt.ReadDir(path)
+	}
+	return ioutil.ReadDir(path)
+}
+
+// SplitPathList behaves like filepath.SplitList,
+// but uses the build context's file system interface, if any.
+func SplitPathList(ctxt *build.Context, s string) []string {
+	if ctxt.SplitPathList != nil {
+		return ctxt.SplitPathList(s)
+	}
+	return filepath.SplitList(s)
+}

Godeps/_workspace/src/golang.org/x/tools/go/buildutil/util_test.go

@@ -0,0 +1,41 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package buildutil_test
+
+import (
+	"go/build"
+	"os"
+	"path/filepath"
+	"runtime"
+	"testing"
+
+	"golang.org/x/tools/go/buildutil"
+)
+
+func TestContainingPackage(t *testing.T) {
+	// unvirtualized:
+	goroot := runtime.GOROOT()
+	gopath := filepath.SplitList(os.Getenv("GOPATH"))[0]
+
+	for _, test := range [][2]string{
+		{goroot + "/src/fmt/print.go", "fmt"},
+		{goroot + "/src/encoding/json/foo.go", "encoding/json"},
+		{goroot + "/src/encoding/missing/foo.go", "(not found)"},
+		{gopath + "/src/golang.org/x/tools/go/buildutil/util_test.go",
+			"golang.org/x/tools/go/buildutil"},
+	} {
+		file, want := test[0], test[1]
+		bp, err := buildutil.ContainingPackage(&build.Default, ".", file)
+		got := bp.ImportPath
+		if err != nil {
+			got = "(not found)"
+		}
+		if got != want {
+			t.Errorf("ContainingPackage(%q) = %s, want %s", file, got, want)
+		}
+	}
+
+	// TODO(adonovan): test on virtualized GOPATH too.
+}

Godeps/_workspace/src/golang.org/x/tools/go/exact/exact.go

@@ -0,0 +1,920 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package exact implements Values representing untyped
+// Go constants and the corresponding operations. Values
+// and operations have unlimited precision.
+//
+// A special Unknown value may be used when a value
+// is unknown due to an error. Operations on unknown
+// values produce unknown values unless specified
+// otherwise.
+//
+package exact
+
+import (
+	"fmt"
+	"go/token"
+	"math/big"
+	"strconv"
+)
+
+// Kind specifies the kind of value represented by a Value.
+type Kind int
+
+// Implementation note: Kinds must be enumerated in
+// order of increasing "complexity" (used by match).
+
+const (
+	// unknown values
+	Unknown Kind = iota
+
+	// non-numeric values
+	Bool
+	String
+
+	// numeric values
+	Int
+	Float
+	Complex
+)
+
+// A Value represents a mathematically exact value of a given Kind.
+type Value interface {
+	// Kind returns the value kind; it is always the smallest
+	// kind in which the value can be represented exactly.
+	Kind() Kind
+
+	// String returns a human-readable form of the value.
+	String() string
+
+	// Prevent external implementations.
+	implementsValue()
+}
+
+// ----------------------------------------------------------------------------
+// Implementations
+
+type (
+	unknownVal struct{}
+	boolVal    bool
+	stringVal  string
+	int64Val   int64
+	intVal     struct{ val *big.Int }
+	floatVal   struct{ val *big.Rat }
+	complexVal struct{ re, im *big.Rat }
+)
+
+func (unknownVal) Kind() Kind { return Unknown }
+func (boolVal) Kind() Kind    { return Bool }
+func (stringVal) Kind() Kind  { return String }
+func (int64Val) Kind() Kind   { return Int }
+func (intVal) Kind() Kind     { return Int }
+func (floatVal) Kind() Kind   { return Float }
+func (complexVal) Kind() Kind { return Complex }
+
+func (unknownVal) String() string   { return "unknown" }
+func (x boolVal) String() string    { return fmt.Sprintf("%v", bool(x)) }
+func (x stringVal) String() string  { return strconv.Quote(string(x)) }
+func (x int64Val) String() string   { return strconv.FormatInt(int64(x), 10) }
+func (x intVal) String() string     { return x.val.String() }
+func (x floatVal) String() string   { return x.val.String() }
+func (x complexVal) String() string { return fmt.Sprintf("(%s + %si)", x.re, x.im) }
+
+func (unknownVal) implementsValue() {}
+func (boolVal) implementsValue()    {}
+func (stringVal) implementsValue()  {}
+func (int64Val) implementsValue()   {}
+func (intVal) implementsValue()     {}
+func (floatVal) implementsValue()   {}
+func (complexVal) implementsValue() {}
+
+// int64 bounds
+var (
+	minInt64 = big.NewInt(-1 << 63)
+	maxInt64 = big.NewInt(1<<63 - 1)
+)
+
+func normInt(x *big.Int) Value {
+	if minInt64.Cmp(x) <= 0 && x.Cmp(maxInt64) <= 0 {
+		return int64Val(x.Int64())
+	}
+	return intVal{x}
+}
+
+func normFloat(x *big.Rat) Value {
+	if x.IsInt() {
+		return normInt(x.Num())
+	}
+	return floatVal{x}
+}
+
+func normComplex(re, im *big.Rat) Value {
+	if im.Sign() == 0 {
+		return normFloat(re)
+	}
+	return complexVal{re, im}
+}
+
+// ----------------------------------------------------------------------------
+// Factories
+
+// MakeUnknown returns the Unknown value.
+func MakeUnknown() Value { return unknownVal{} }
+
+// MakeBool returns the Bool value for x.
+func MakeBool(b bool) Value { return boolVal(b) }
+
+// MakeString returns the String value for x.
+func MakeString(s string) Value { return stringVal(s) }
+
+// MakeInt64 returns the Int value for x.
+func MakeInt64(x int64) Value { return int64Val(x) }
+
+// MakeUint64 returns the Int value for x.
+func MakeUint64(x uint64) Value { return normInt(new(big.Int).SetUint64(x)) }
+
+// MakeFloat64 returns the numeric value for x.
+// If x is not finite, the result is unknown.
+func MakeFloat64(x float64) Value {
+	if f := new(big.Rat).SetFloat64(x); f != nil {
+		return normFloat(f)
+	}
+	return unknownVal{}
+}
+
+// MakeFromLiteral returns the corresponding integer, floating-point,
+// imaginary, character, or string value for a Go literal string. The
+// result is nil if the literal string is invalid.
+func MakeFromLiteral(lit string, tok token.Token) Value {
+	switch tok {
+	case token.INT:
+		if x, err := strconv.ParseInt(lit, 0, 64); err == nil {
+			return int64Val(x)
+		}
+		if x, ok := new(big.Int).SetString(lit, 0); ok {
+			return intVal{x}
+		}
+
+	case token.FLOAT:
+		if x, ok := new(big.Rat).SetString(lit); ok {
+			return normFloat(x)
+		}
+
+	case token.IMAG:
+		if n := len(lit); n > 0 && lit[n-1] == 'i' {
+			if im, ok := new(big.Rat).SetString(lit[0 : n-1]); ok {
+				return normComplex(big.NewRat(0, 1), im)
+			}
+		}
+
+	case token.CHAR:
+		if n := len(lit); n >= 2 {
+			if code, _, _, err := strconv.UnquoteChar(lit[1:n-1], '\''); err == nil {
+				return int64Val(code)
+			}
+		}
+
+	case token.STRING:
+		if s, err := strconv.Unquote(lit); err == nil {
+			return stringVal(s)
+		}
+	}
+
+	return nil
+}
+
+// ----------------------------------------------------------------------------
+// Accessors
+//
+// For unknown arguments the result is the zero value for the respective
+// accessor type, except for Sign, where the result is 1.
+
+// BoolVal returns the Go boolean value of x, which must be a Bool or an Unknown.
+// If x is Unknown, the result is false.
+func BoolVal(x Value) bool {
+	switch x := x.(type) {
+	case boolVal:
+		return bool(x)
+	case unknownVal:
+		return false
+	}
+	panic(fmt.Sprintf("%v not a Bool", x))
+}
+
+// StringVal returns the Go string value of x, which must be a String or an Unknown.
+// If x is Unknown, the result is "".
+func StringVal(x Value) string {
+	switch x := x.(type) {
+	case stringVal:
+		return string(x)
+	case unknownVal:
+		return ""
+	}
+	panic(fmt.Sprintf("%v not a String", x))
+}
+
+// Int64Val returns the Go int64 value of x and whether the result is exact;
+// x must be an Int or an Unknown. If the result is not exact, its value is undefined.
+// If x is Unknown, the result is (0, false).
+func Int64Val(x Value) (int64, bool) {
+	switch x := x.(type) {
+	case int64Val:
+		return int64(x), true
+	case intVal:
+		return x.val.Int64(), x.val.BitLen() <= 63
+	case unknownVal:
+		return 0, false
+	}
+	panic(fmt.Sprintf("%v not an Int", x))
+}
+
+// Uint64Val returns the Go uint64 value of x and whether the result is exact;
+// x must be an Int or an Unknown. If the result is not exact, its value is undefined.
+// If x is Unknown, the result is (0, false).
+func Uint64Val(x Value) (uint64, bool) {
+	switch x := x.(type) {
+	case int64Val:
+		return uint64(x), x >= 0
+	case intVal:
+		return x.val.Uint64(), x.val.Sign() >= 0 && x.val.BitLen() <= 64
+	case unknownVal:
+		return 0, false
+	}
+	panic(fmt.Sprintf("%v not an Int", x))
+}
+
+// Float32Val is like Float64Val but for float32 instead of float64.
+func Float32Val(x Value) (float32, bool) {
+	switch x := x.(type) {
+	case int64Val:
+		f := float32(x)
+		return f, int64Val(f) == x
+	case intVal:
+		return ratToFloat32(new(big.Rat).SetFrac(x.val, int1))
+	case floatVal:
+		return ratToFloat32(x.val)
+	case unknownVal:
+		return 0, false
+	}
+	panic(fmt.Sprintf("%v not a Float", x))
+}
+
+// Float64Val returns the nearest Go float64 value of x and whether the result is exact;
+// x must be numeric but not Complex, or Unknown. For values too small (too close to 0)
+// to represent as float64, Float64Val silently underflows to 0. The result sign always
+// matches the sign of x, even for 0.
+// If x is Unknown, the result is (0, false).
+func Float64Val(x Value) (float64, bool) {
+	switch x := x.(type) {
+	case int64Val:
+		f := float64(int64(x))
+		return f, int64Val(f) == x
+	case intVal:
+		return new(big.Rat).SetFrac(x.val, int1).Float64()
+	case floatVal:
+		return x.val.Float64()
+	case unknownVal:
+		return 0, false
+	}
+	panic(fmt.Sprintf("%v not a Float", x))
+}
+
+// BitLen returns the number of bits required to represent
+// the absolute value x in binary representation; x must be an Int or an Unknown.
+// If x is Unknown, the result is 0.
+func BitLen(x Value) int {
+	switch x := x.(type) {
+	case int64Val:
+		return new(big.Int).SetInt64(int64(x)).BitLen()
+	case intVal:
+		return x.val.BitLen()
+	case unknownVal:
+		return 0
+	}
+	panic(fmt.Sprintf("%v not an Int", x))
+}
+
+// Sign returns -1, 0, or 1 depending on whether x < 0, x == 0, or x > 0;
+// x must be numeric or Unknown. For complex values x, the sign is 0 if x == 0,
+// otherwise it is != 0. If x is Unknown, the result is 1.
+func Sign(x Value) int {
+	switch x := x.(type) {
+	case int64Val:
+		switch {
+		case x < 0:
+			return -1
+		case x > 0:
+			return 1
+		}
+		return 0
+	case intVal:
+		return x.val.Sign()
+	case floatVal:
+		return x.val.Sign()
+	case complexVal:
+		return x.re.Sign() | x.im.Sign()
+	case unknownVal:
+		return 1 // avoid spurious division by zero errors
+	}
+	panic(fmt.Sprintf("%v not numeric", x))
+}
+
+// ----------------------------------------------------------------------------
+// Support for serializing/deserializing integers
+
+const (
+	// Compute the size of a Word in bytes.
+	_m       = ^big.Word(0)
+	_log     = _m>>8&1 + _m>>16&1 + _m>>32&1
+	wordSize = 1 << _log
+)
+
+// Bytes returns the bytes for the absolute value of x in little-
+// endian binary representation; x must be an Int.
+func Bytes(x Value) []byte {
+	var val *big.Int
+	switch x := x.(type) {
+	case int64Val:
+		val = new(big.Int).SetInt64(int64(x))
+	case intVal:
+		val = x.val
+	default:
+		panic(fmt.Sprintf("%v not an Int", x))
+	}
+
+	words := val.Bits()
+	bytes := make([]byte, len(words)*wordSize)
+
+	i := 0
+	for _, w := range words {
+		for j := 0; j < wordSize; j++ {
+			bytes[i] = byte(w)
+			w >>= 8
+			i++
+		}
+	}
+	// remove leading 0's
+	for i > 0 && bytes[i-1] == 0 {
+		i--
+	}
+
+	return bytes[:i]
+}
+
+// MakeFromBytes returns the Int value given the bytes of its little-endian
+// binary representation. An empty byte slice argument represents 0.
+func MakeFromBytes(bytes []byte) Value {
+	words := make([]big.Word, (len(bytes)+(wordSize-1))/wordSize)
+
+	i := 0
+	var w big.Word
+	var s uint
+	for _, b := range bytes {
+		w |= big.Word(b) << s
+		if s += 8; s == wordSize*8 {
+			words[i] = w
+			i++
+			w = 0
+			s = 0
+		}
+	}
+	// store last word
+	if i < len(words) {
+		words[i] = w
+		i++
+	}
+	// remove leading 0's
+	for i > 0 && words[i-1] == 0 {
+		i--
+	}
+
+	return normInt(new(big.Int).SetBits(words[:i]))
+}
+
+// ----------------------------------------------------------------------------
+// Support for disassembling fractions
+
+// Num returns the numerator of x; x must be Int, Float, or Unknown.
+// If x is Unknown, the result is Unknown, otherwise it is an Int
+// with the same sign as x.
+func Num(x Value) Value {
+	switch x := x.(type) {
+	case unknownVal, int64Val, intVal:
+		return x
+	case floatVal:
+		return normInt(x.val.Num())
+	}
+	panic(fmt.Sprintf("%v not Int or Float", x))
+}
+
+// Denom returns the denominator of x; x must be Int, Float, or Unknown.
+// If x is Unknown, the result is Unknown, otherwise it is an Int >= 1.
+func Denom(x Value) Value {
+	switch x := x.(type) {
+	case unknownVal:
+		return x
+	case int64Val, intVal:
+		return int64Val(1)
+	case floatVal:
+		return normInt(x.val.Denom())
+	}
+	panic(fmt.Sprintf("%v not Int or Float", x))
+}
+
+// ----------------------------------------------------------------------------
+// Support for assembling/disassembling complex numbers
+
+// MakeImag returns the numeric value x*i (possibly 0);
+// x must be Int, Float, or Unknown.
+// If x is Unknown, the result is Unknown.
+func MakeImag(x Value) Value {
+	var im *big.Rat
+	switch x := x.(type) {
+	case unknownVal:
+		return x
+	case int64Val:
+		im = big.NewRat(int64(x), 1)
+	case intVal:
+		im = new(big.Rat).SetFrac(x.val, int1)
+	case floatVal:
+		im = x.val
+	default:
+		panic(fmt.Sprintf("%v not Int or Float", x))
+	}
+	return normComplex(rat0, im)
+}
+
+// Real returns the real part of x, which must be a numeric or unknown value.
+// If x is Unknown, the result is Unknown.
+func Real(x Value) Value {
+	switch x := x.(type) {
+	case unknownVal, int64Val, intVal, floatVal:
+		return x
+	case complexVal:
+		return normFloat(x.re)
+	}
+	panic(fmt.Sprintf("%v not numeric", x))
+}
+
+// Imag returns the imaginary part of x, which must be a numeric or unknown value.
+// If x is Unknown, the result is Unknown.
+func Imag(x Value) Value {
+	switch x := x.(type) {
+	case unknownVal:
+		return x
+	case int64Val, intVal, floatVal:
+		return int64Val(0)
+	case complexVal:
+		return normFloat(x.im)
+	}
+	panic(fmt.Sprintf("%v not numeric", x))
+}
+
+// ----------------------------------------------------------------------------
+// Operations
+
+// is32bit reports whether x can be represented using 32 bits.
+func is32bit(x int64) bool {
+	const s = 32
+	return -1<<(s-1) <= x && x <= 1<<(s-1)-1
+}
+
+// is63bit reports whether x can be represented using 63 bits.
+func is63bit(x int64) bool {
+	const s = 63
+	return -1<<(s-1) <= x && x <= 1<<(s-1)-1
+}
+
+// UnaryOp returns the result of the unary expression op y.
+// The operation must be defined for the operand.
+// If size >= 0 it specifies the ^ (xor) result size in bytes.
+// If y is Unknown, the result is Unknown.
+//
+func UnaryOp(op token.Token, y Value, size int) Value {
+	switch op {
+	case token.ADD:
+		switch y.(type) {
+		case unknownVal, int64Val, intVal, floatVal, complexVal:
+			return y
+		}
+
+	case token.SUB:
+		switch y := y.(type) {
+		case unknownVal:
+			return y
+		case int64Val:
+			if z := -y; z != y {
+				return z // no overflow
+			}
+			return normInt(new(big.Int).Neg(big.NewInt(int64(y))))
+		case intVal:
+			return normInt(new(big.Int).Neg(y.val))
+		case floatVal:
+			return normFloat(new(big.Rat).Neg(y.val))
+		case complexVal:
+			return normComplex(new(big.Rat).Neg(y.re), new(big.Rat).Neg(y.im))
+		}
+
+	case token.XOR:
+		var z big.Int
+		switch y := y.(type) {
+		case unknownVal:
+			return y
+		case int64Val:
+			z.Not(big.NewInt(int64(y)))
+		case intVal:
+			z.Not(y.val)
+		default:
+			goto Error
+		}
+		// For unsigned types, the result will be negative and
+		// thus "too large": We must limit the result size to
+		// the type's size.
+		if size >= 0 {
+			s := uint(size) * 8
+			z.AndNot(&z, new(big.Int).Lsh(big.NewInt(-1), s)) // z &^= (-1)<<s
+		}
+		return normInt(&z)
+
+	case token.NOT:
+		switch y := y.(type) {
+		case unknownVal:
+			return y
+		case boolVal:
+			return !y
+		}
+	}
+
+Error:
+	panic(fmt.Sprintf("invalid unary operation %s%v", op, y))
+}
+
+var (
+	int1 = big.NewInt(1)
+	rat0 = big.NewRat(0, 1)
+)
+
+func ord(x Value) int {
+	switch x.(type) {
+	default:
+		return 0
+	case boolVal, stringVal:
+		return 1
+	case int64Val:
+		return 2
+	case intVal:
+		return 3
+	case floatVal:
+		return 4
+	case complexVal:
+		return 5
+	}
+}
+
+// match returns the matching representation (same type) with the
+// smallest complexity for two values x and y. If one of them is
+// numeric, both of them must be numeric. If one of them is Unknown,
+// both results are Unknown.
+//
+func match(x, y Value) (_, _ Value) {
+	if ord(x) > ord(y) {
+		y, x = match(y, x)
+		return x, y
+	}
+	// ord(x) <= ord(y)
+
+	switch x := x.(type) {
+	case unknownVal:
+		return x, x
+
+	case boolVal, stringVal, complexVal:
+		return x, y
+
+	case int64Val:
+		switch y := y.(type) {
+		case int64Val:
+			return x, y
+		case intVal:
+			return intVal{big.NewInt(int64(x))}, y
+		case floatVal:
+			return floatVal{big.NewRat(int64(x), 1)}, y
+		case complexVal:
+			return complexVal{big.NewRat(int64(x), 1), rat0}, y
+		}
+
+	case intVal:
+		switch y := y.(type) {
+		case intVal:
+			return x, y
+		case floatVal:
+			return floatVal{new(big.Rat).SetFrac(x.val, int1)}, y
+		case complexVal:
+			return complexVal{new(big.Rat).SetFrac(x.val, int1), rat0}, y
+		}
+
+	case floatVal:
+		switch y := y.(type) {
+		case floatVal:
+			return x, y
+		case complexVal:
+			return complexVal{x.val, rat0}, y
+		}
+	}
+
+	panic("unreachable")
+}
+
+// BinaryOp returns the result of the binary expression x op y.
+// The operation must be defined for the operands. If one of the
+// operands is Unknown, the result is Unknown.
+// To force integer division of Int operands, use op == token.QUO_ASSIGN
+// instead of token.QUO; the result is guaranteed to be Int in this case.
+// Division by zero leads to a run-time panic.
+//
+func BinaryOp(x Value, op token.Token, y Value) Value {
+	x, y = match(x, y)
+
+	switch x := x.(type) {
+	case unknownVal:
+		return x
+
+	case boolVal:
+		y := y.(boolVal)
+		switch op {
+		case token.LAND:
+			return x && y
+		case token.LOR:
+			return x || y
+		}
+
+	case int64Val:
+		a := int64(x)
+		b := int64(y.(int64Val))
+		var c int64
+		switch op {
+		case token.ADD:
+			if !is63bit(a) || !is63bit(b) {
+				return normInt(new(big.Int).Add(big.NewInt(a), big.NewInt(b)))
+			}
+			c = a + b
+		case token.SUB:
+			if !is63bit(a) || !is63bit(b) {
+				return normInt(new(big.Int).Sub(big.NewInt(a), big.NewInt(b)))
+			}
+			c = a - b
+		case token.MUL:
+			if !is32bit(a) || !is32bit(b) {
+				return normInt(new(big.Int).Mul(big.NewInt(a), big.NewInt(b)))
+			}
+			c = a * b
+		case token.QUO:
+			return normFloat(new(big.Rat).SetFrac(big.NewInt(a), big.NewInt(b)))
+		case token.QUO_ASSIGN: // force integer division
+			c = a / b
+		case token.REM:
+			c = a % b
+		case token.AND:
+			c = a & b
+		case token.OR:
+			c = a | b
+		case token.XOR:
+			c = a ^ b
+		case token.AND_NOT:
+			c = a &^ b
+		default:
+			goto Error
+		}
+		return int64Val(c)
+
+	case intVal:
+		a := x.val
+		b := y.(intVal).val
+		var c big.Int
+		switch op {
+		case token.ADD:
+			c.Add(a, b)
+		case token.SUB:
+			c.Sub(a, b)
+		case token.MUL:
+			c.Mul(a, b)
+		case token.QUO:
+			return normFloat(new(big.Rat).SetFrac(a, b))
+		case token.QUO_ASSIGN: // force integer division
+			c.Quo(a, b)
+		case token.REM:
+			c.Rem(a, b)
+		case token.AND:
+			c.And(a, b)
+		case token.OR:
+			c.Or(a, b)
+		case token.XOR:
+			c.Xor(a, b)
+		case token.AND_NOT:
+			c.AndNot(a, b)
+		default:
+			goto Error
+		}
+		return normInt(&c)
+
+	case floatVal:
+		a := x.val
+		b := y.(floatVal).val
+		var c big.Rat
+		switch op {
+		case token.ADD:
+			c.Add(a, b)
+		case token.SUB:
+			c.Sub(a, b)
+		case token.MUL:
+			c.Mul(a, b)
+		case token.QUO:
+			c.Quo(a, b)
+		default:
+			goto Error
+		}
+		return normFloat(&c)
+
+	case complexVal:
+		y := y.(complexVal)
+		a, b := x.re, x.im
+		c, d := y.re, y.im
+		var re, im big.Rat
+		switch op {
+		case token.ADD:
+			// (a+c) + i(b+d)
+			re.Add(a, c)
+			im.Add(b, d)
+		case token.SUB:
+			// (a-c) + i(b-d)
+			re.Sub(a, c)
+			im.Sub(b, d)
+		case token.MUL:
+			// (ac-bd) + i(bc+ad)
+			var ac, bd, bc, ad big.Rat
+			ac.Mul(a, c)
+			bd.Mul(b, d)
+			bc.Mul(b, c)
+			ad.Mul(a, d)
+			re.Sub(&ac, &bd)
+			im.Add(&bc, &ad)
+		case token.QUO:
+			// (ac+bd)/s + i(bc-ad)/s, with s = cc + dd
+			var ac, bd, bc, ad, s, cc, dd big.Rat
+			ac.Mul(a, c)
+			bd.Mul(b, d)
+			bc.Mul(b, c)
+			ad.Mul(a, d)
+			cc.Mul(c, c)
+			dd.Mul(d, d)
+			s.Add(&cc, &dd)
+			re.Add(&ac, &bd)
+			re.Quo(&re, &s)
+			im.Sub(&bc, &ad)
+			im.Quo(&im, &s)
+		default:
+			goto Error
+		}
+		return normComplex(&re, &im)
+
+	case stringVal:
+		if op == token.ADD {
+			return x + y.(stringVal)
+		}
+	}
+
+Error:
+	panic(fmt.Sprintf("invalid binary operation %v %s %v", x, op, y))
+}
+
+// Shift returns the result of the shift expression x op s
+// with op == token.SHL or token.SHR (<< or >>). x must be
+// an Int or an Unknown. If x is Unknown, the result is x.
+//
+func Shift(x Value, op token.Token, s uint) Value {
+	switch x := x.(type) {
+	case unknownVal:
+		return x
+
+	case int64Val:
+		if s == 0 {
+			return x
+		}
+		switch op {
+		case token.SHL:
+			z := big.NewInt(int64(x))
+			return normInt(z.Lsh(z, s))
+		case token.SHR:
+			return x >> s
+		}
+
+	case intVal:
+		if s == 0 {
+			return x
+		}
+		var z big.Int
+		switch op {
+		case token.SHL:
+			return normInt(z.Lsh(x.val, s))
+		case token.SHR:
+			return normInt(z.Rsh(x.val, s))
+		}
+	}
+
+	panic(fmt.Sprintf("invalid shift %v %s %d", x, op, s))
+}
+
+func cmpZero(x int, op token.Token) bool {
+	switch op {
+	case token.EQL:
+		return x == 0
+	case token.NEQ:
+		return x != 0
+	case token.LSS:
+		return x < 0
+	case token.LEQ:
+		return x <= 0
+	case token.GTR:
+		return x > 0
+	case token.GEQ:
+		return x >= 0
+	}
+	panic("unreachable")
+}
+
+// Compare returns the result of the comparison x op y.
+// The comparison must be defined for the operands.
+// If one of the operands is Unknown, the result is
+// false.
+//
+func Compare(x Value, op token.Token, y Value) bool {
+	x, y = match(x, y)
+
+	switch x := x.(type) {
+	case unknownVal:
+		return false
+
+	case boolVal:
+		y := y.(boolVal)
+		switch op {
+		case token.EQL:
+			return x == y
+		case token.NEQ:
+			return x != y
+		}
+
+	case int64Val:
+		y := y.(int64Val)
+		switch op {
+		case token.EQL:
+			return x == y
+		case token.NEQ:
+			return x != y
+		case token.LSS:
+			return x < y
+		case token.LEQ:
+			return x <= y
+		case token.GTR:
+			return x > y
+		case token.GEQ:
+			return x >= y
+		}
+
+	case intVal:
+		return cmpZero(x.val.Cmp(y.(intVal).val), op)
+
+	case floatVal:
+		return cmpZero(x.val.Cmp(y.(floatVal).val), op)
+
+	case complexVal:
+		y := y.(complexVal)
+		re := x.re.Cmp(y.re)
+		im := x.im.Cmp(y.im)
+		switch op {
+		case token.EQL:
+			return re == 0 && im == 0
+		case token.NEQ:
+			return re != 0 || im != 0
+		}
+
+	case stringVal:
+		y := y.(stringVal)
+		switch op {
+		case token.EQL:
+			return x == y
+		case token.NEQ:
+			return x != y
+		case token.LSS:
+			return x < y
+		case token.LEQ:
+			return x <= y
+		case token.GTR:
+			return x > y
+		case token.GEQ:
+			return x >= y
+		}
+	}
+
+	panic(fmt.Sprintf("invalid comparison %v %s %v", x, op, y))
+}

Godeps/_workspace/src/golang.org/x/tools/go/exact/exact_test.go

@@ -0,0 +1,375 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package exact
+
+import (
+	"go/token"
+	"strings"
+	"testing"
+)
+
+// TODO(gri) expand this test framework
+
+var opTests = []string{
+	// unary operations
+	`+ 0 = 0`,
+	`+ ? = ?`,
+	`- 1 = -1`,
+	`- ? = ?`,
+	`^ 0 = -1`,
+	`^ ? = ?`,
+
+	`! true = false`,
+	`! false = true`,
+	`! ? = ?`,
+
+	// etc.
+
+	// binary operations
+	`"" + "" = ""`,
+	`"foo" + "" = "foo"`,
+	`"" + "bar" = "bar"`,
+	`"foo" + "bar" = "foobar"`,
+
+	`0 + 0 = 0`,
+	`0 + 0.1 = 0.1`,
+	`0 + 0.1i = 0.1i`,
+	`0.1 + 0.9 = 1`,
+	`1e100 + 1e100 = 2e100`,
+	`? + 0 = ?`,
+	`0 + ? = ?`,
+
+	`0 - 0 = 0`,
+	`0 - 0.1 = -0.1`,
+	`0 - 0.1i = -0.1i`,
+	`1e100 - 1e100 = 0`,
+	`? - 0 = ?`,
+	`0 - ? = ?`,
+
+	`0 * 0 = 0`,
+	`1 * 0.1 = 0.1`,
+	`1 * 0.1i = 0.1i`,
+	`1i * 1i = -1`,
+	`? * 0 = ?`,
+	`0 * ? = ?`,
+
+	`0 / 0 = "division_by_zero"`,
+	`10 / 2 = 5`,
+	`5 / 3 = 5/3`,
+	`5i / 3i = 5/3`,
+	`? / 0 = ?`,
+	`0 / ? = ?`,
+
+	`0 % 0 = "runtime_error:_integer_divide_by_zero"`, // TODO(gri) should be the same as for /
+	`10 % 3 = 1`,
+	`? % 0 = ?`,
+	`0 % ? = ?`,
+
+	`0 & 0 = 0`,
+	`12345 & 0 = 0`,
+	`0xff & 0xf = 0xf`,
+	`? & 0 = ?`,
+	`0 & ? = ?`,
+
+	`0 | 0 = 0`,
+	`12345 | 0 = 12345`,
+	`0xb | 0xa0 = 0xab`,
+	`? | 0 = ?`,
+	`0 | ? = ?`,
+
+	`0 ^ 0 = 0`,
+	`1 ^ -1 = -2`,
+	`? ^ 0 = ?`,
+	`0 ^ ? = ?`,
+
+	`0 &^ 0 = 0`,
+	`0xf &^ 1 = 0xe`,
+	`1 &^ 0xf = 0`,
+	// etc.
+
+	// shifts
+	`0 << 0 = 0`,
+	`1 << 10 = 1024`,
+	`0 >> 0 = 0`,
+	`1024 >> 10 == 1`,
+	`? << 0 == ?`,
+	`? >> 10 == ?`,
+	// etc.
+
+	// comparisons
+	`false == false = true`,
+	`false == true = false`,
+	`true == false = false`,
+	`true == true = true`,
+
+	`false != false = false`,
+	`false != true = true`,
+	`true != false = true`,
+	`true != true = false`,
+
+	`"foo" == "bar" = false`,
+	`"foo" != "bar" = true`,
+	`"foo" < "bar" = false`,
+	`"foo" <= "bar" = false`,
+	`"foo" > "bar" = true`,
+	`"foo" >= "bar" = true`,
+
+	`0 == 0 = true`,
+	`0 != 0 = false`,
+	`0 < 10 = true`,
+	`10 <= 10 = true`,
+	`0 > 10 = false`,
+	`10 >= 10 = true`,
+
+	`1/123456789 == 1/123456789 == true`,
+	`1/123456789 != 1/123456789 == false`,
+	`1/123456789 < 1/123456788 == true`,
+	`1/123456788 <= 1/123456789 == false`,
+	`0.11 > 0.11 = false`,
+	`0.11 >= 0.11 = true`,
+
+	`? == 0 = false`,
+	`? != 0 = false`,
+	`? < 10 = false`,
+	`? <= 10 = false`,
+	`? > 10 = false`,
+	`? >= 10 = false`,
+
+	`0 == ? = false`,
+	`0 != ? = false`,
+	`0 < ? = false`,
+	`10 <= ? = false`,
+	`0 > ? = false`,
+	`10 >= ? = false`,
+
+	// etc.
+}
+
+func TestOps(t *testing.T) {
+	for _, test := range opTests {
+		a := strings.Split(test, " ")
+		i := 0 // operator index
+
+		var x, x0 Value
+		switch len(a) {
+		case 4:
+			// unary operation
+		case 5:
+			// binary operation
+			x, x0 = val(a[0]), val(a[0])
+			i = 1
+		default:
+			t.Errorf("invalid test case: %s", test)
+			continue
+		}
+
+		op, ok := optab[a[i]]
+		if !ok {
+			panic("missing optab entry for " + a[i])
+		}
+
+		y, y0 := val(a[i+1]), val(a[i+1])
+
+		got := doOp(x, op, y)
+		want := val(a[i+3])
+		if !eql(got, want) {
+			t.Errorf("%s: got %s; want %s", test, got, want)
+		}
+		if x0 != nil && !eql(x, x0) {
+			t.Errorf("%s: x changed to %s", test, x)
+		}
+		if !eql(y, y0) {
+			t.Errorf("%s: y changed to %s", test, y)
+		}
+	}
+}
+
+func eql(x, y Value) bool {
+	_, ux := x.(unknownVal)
+	_, uy := y.(unknownVal)
+	if ux || uy {
+		return ux == uy
+	}
+	return Compare(x, token.EQL, y)
+}
+
+// ----------------------------------------------------------------------------
+// Support functions
+
+func val(lit string) Value {
+	if len(lit) == 0 {
+		return MakeUnknown()
+	}
+
+	switch lit {
+	case "?":
+		return MakeUnknown()
+	case "true":
+		return MakeBool(true)
+	case "false":
+		return MakeBool(false)
+	}
+
+	tok := token.INT
+	switch first, last := lit[0], lit[len(lit)-1]; {
+	case first == '"' || first == '`':
+		tok = token.STRING
+		lit = strings.Replace(lit, "_", " ", -1)
+	case first == '\'':
+		tok = token.CHAR
+	case last == 'i':
+		tok = token.IMAG
+	default:
+		if !strings.HasPrefix(lit, "0x") && strings.ContainsAny(lit, "./Ee") {
+			tok = token.FLOAT
+		}
+	}
+
+	return MakeFromLiteral(lit, tok)
+}
+
+var optab = map[string]token.Token{
+	"!": token.NOT,
+
+	"+": token.ADD,
+	"-": token.SUB,
+	"*": token.MUL,
+	"/": token.QUO,
+	"%": token.REM,
+
+	"<<": token.SHL,
+	">>": token.SHR,
+
+	"&":  token.AND,
+	"|":  token.OR,
+	"^":  token.XOR,
+	"&^": token.AND_NOT,
+
+	"==": token.EQL,
+	"!=": token.NEQ,
+	"<":  token.LSS,
+	"<=": token.LEQ,
+	">":  token.GTR,
+	">=": token.GEQ,
+}
+
+func panicHandler(v *Value) {
+	switch p := recover().(type) {
+	case nil:
+		// nothing to do
+	case string:
+		*v = MakeString(p)
+	case error:
+		*v = MakeString(p.Error())
+	default:
+		panic(p)
+	}
+}
+
+func doOp(x Value, op token.Token, y Value) (z Value) {
+	defer panicHandler(&z)
+
+	if x == nil {
+		return UnaryOp(op, y, -1)
+	}
+
+	switch op {
+	case token.EQL, token.NEQ, token.LSS, token.LEQ, token.GTR, token.GEQ:
+		return MakeBool(Compare(x, op, y))
+	case token.SHL, token.SHR:
+		s, _ := Int64Val(y)
+		return Shift(x, op, uint(s))
+	default:
+		return BinaryOp(x, op, y)
+	}
+}
+
+// ----------------------------------------------------------------------------
+// Other tests
+
+var fracTests = []string{
+	"0 0 1",
+	"1 1 1",
+	"-1 -1 1",
+	"1.2 6 5",
+	"-0.991 -991 1000",
+	"1e100 1e100 1",
+}
+
+func TestFractions(t *testing.T) {
+	for _, test := range fracTests {
+		a := strings.Split(test, " ")
+		if len(a) != 3 {
+			t.Errorf("invalid test case: %s", test)
+			continue
+		}
+
+		x := val(a[0])
+		n := val(a[1])
+		d := val(a[2])
+
+		if got := Num(x); !eql(got, n) {
+			t.Errorf("%s: got num = %s; want %s", test, got, n)
+		}
+
+		if got := Denom(x); !eql(got, d) {
+			t.Errorf("%s: got denom = %s; want %s", test, got, d)
+		}
+	}
+}
+
+var bytesTests = []string{
+	"0",
+	"1",
+	"123456789",
+	"123456789012345678901234567890123456789012345678901234567890",
+}
+
+func TestBytes(t *testing.T) {
+	for _, test := range bytesTests {
+		x := val(test)
+		bytes := Bytes(x)
+
+		// special case 0
+		if Sign(x) == 0 && len(bytes) != 0 {
+			t.Errorf("%s: got %v; want empty byte slice", test, bytes)
+		}
+
+		if n := len(bytes); n > 0 && bytes[n-1] == 0 {
+			t.Errorf("%s: got %v; want no leading 0 byte", test, bytes)
+		}
+
+		if got := MakeFromBytes(bytes); !eql(got, x) {
+			t.Errorf("%s: got %s; want %s (bytes = %v)", test, got, x, bytes)
+		}
+	}
+}
+
+func TestUnknown(t *testing.T) {
+	u := MakeUnknown()
+	var values = []Value{
+		u,
+		MakeBool(false), // token.ADD ok below, operation is never considered
+		MakeString(""),
+		MakeInt64(1),
+		MakeFromLiteral("-1234567890123456789012345678901234567890", token.INT),
+		MakeFloat64(1.2),
+		MakeImag(MakeFloat64(1.2)),
+	}
+	for _, val := range values {
+		x, y := val, u
+		for i := range [2]int{} {
+			if i == 1 {
+				x, y = y, x
+			}
+			if got := BinaryOp(x, token.ADD, y); got.Kind() != Unknown {
+				t.Errorf("%s + %s: got %s; want %s", x, y, got, u)
+			}
+			if got := Compare(x, token.EQL, y); got {
+				t.Errorf("%s == %s: got true; want false", x, y)
+			}
+		}
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/exact/go13.go

@@ -0,0 +1,24 @@
+// Copyright 2014 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !go1.4
+
+package exact
+
+import (
+	"math"
+	"math/big"
+)
+
+func ratToFloat32(x *big.Rat) (float32, bool) {
+	// Before 1.4, there's no Rat.Float32.
+	// Emulate it, albeit at the cost of
+	// imprecision in corner cases.
+	x64, exact := x.Float64()
+	x32 := float32(x64)
+	if math.IsInf(float64(x32), 0) {
+		exact = false
+	}
+	return x32, exact
+}

Godeps/_workspace/src/golang.org/x/tools/go/exact/go14.go

@@ -0,0 +1,13 @@
+// Copyright 2014 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.4
+
+package exact
+
+import "math/big"
+
+func ratToFloat32(x *big.Rat) (float32, bool) {
+	return x.Float32()
+}

Godeps/_workspace/src/golang.org/x/tools/go/loader/cgo.go

@@ -0,0 +1,199 @@
+package loader
+
+// This file handles cgo preprocessing of files containing `import "C"`.
+//
+// DESIGN
+//
+// The approach taken is to run the cgo processor on the package's
+// CgoFiles and parse the output, faking the filenames of the
+// resulting ASTs so that the synthetic file containing the C types is
+// called "C" (e.g. "~/go/src/net/C") and the preprocessed files
+// have their original names (e.g. "~/go/src/net/cgo_unix.go"),
+// not the names of the actual temporary files.
+//
+// The advantage of this approach is its fidelity to 'go build'.  The
+// downside is that the token.Position.Offset for each AST node is
+// incorrect, being an offset within the temporary file.  Line numbers
+// should still be correct because of the //line comments.
+//
+// The logic of this file is mostly plundered from the 'go build'
+// tool, which also invokes the cgo preprocessor.
+//
+//
+// REJECTED ALTERNATIVE
+//
+// An alternative approach that we explored is to extend go/types'
+// Importer mechanism to provide the identity of the importing package
+// so that each time `import "C"` appears it resolves to a different
+// synthetic package containing just the objects needed in that case.
+// The loader would invoke cgo but parse only the cgo_types.go file
+// defining the package-level objects, discarding the other files
+// resulting from preprocessing.
+//
+// The benefit of this approach would have been that source-level
+// syntax information would correspond exactly to the original cgo
+// file, with no preprocessing involved, making source tools like
+// godoc, oracle, and eg happy.  However, the approach was rejected
+// due to the additional complexity it would impose on go/types.  (It
+// made for a beautiful demo, though.)
+//
+// cgo files, despite their *.go extension, are not legal Go source
+// files per the specification since they may refer to unexported
+// members of package "C" such as C.int.  Also, a function such as
+// C.getpwent has in effect two types, one matching its C type and one
+// which additionally returns (errno C.int).  The cgo preprocessor
+// uses name mangling to distinguish these two functions in the
+// processed code, but go/types would need to duplicate this logic in
+// its handling of function calls, analogous to the treatment of map
+// lookups in which y=m[k] and y,ok=m[k] are both legal.
+
+import (
+	"fmt"
+	"go/ast"
+	"go/build"
+	"go/parser"
+	"go/token"
+	"io/ioutil"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"regexp"
+	"strings"
+)
+
+// processCgoFiles invokes the cgo preprocessor on bp.CgoFiles, parses
+// the output and returns the resulting ASTs.
+//
+func processCgoFiles(bp *build.Package, fset *token.FileSet, DisplayPath func(path string) string, mode parser.Mode) ([]*ast.File, error) {
+	tmpdir, err := ioutil.TempDir("", strings.Replace(bp.ImportPath, "/", "_", -1)+"_C")
+	if err != nil {
+		return nil, err
+	}
+	defer os.RemoveAll(tmpdir)
+
+	pkgdir := bp.Dir
+	if DisplayPath != nil {
+		pkgdir = DisplayPath(pkgdir)
+	}
+
+	cgoFiles, cgoDisplayFiles, err := runCgo(bp, pkgdir, tmpdir)
+	if err != nil {
+		return nil, err
+	}
+	var files []*ast.File
+	for i := range cgoFiles {
+		rd, err := os.Open(cgoFiles[i])
+		if err != nil {
+			return nil, err
+		}
+		defer rd.Close()
+		display := filepath.Join(bp.Dir, cgoDisplayFiles[i])
+		f, err := parser.ParseFile(fset, display, rd, mode)
+		if err != nil {
+			return nil, err
+		}
+		files = append(files, f)
+	}
+	return files, nil
+}
+
+var cgoRe = regexp.MustCompile(`[/\\:]`)
+
+// runCgo invokes the cgo preprocessor on bp.CgoFiles and returns two
+// lists of files: the resulting processed files (in temporary
+// directory tmpdir) and the corresponding names of the unprocessed files.
+//
+// runCgo is adapted from (*builder).cgo in
+// $GOROOT/src/cmd/go/build.go, but these features are unsupported:
+// pkg-config, Objective C, CGOPKGPATH, CGO_FLAGS.
+//
+func runCgo(bp *build.Package, pkgdir, tmpdir string) (files, displayFiles []string, err error) {
+	cgoCPPFLAGS, _, _, _ := cflags(bp, true)
+	_, cgoexeCFLAGS, _, _ := cflags(bp, false)
+
+	if len(bp.CgoPkgConfig) > 0 {
+		return nil, nil, fmt.Errorf("cgo pkg-config not supported")
+	}
+
+	// Allows including _cgo_export.h from .[ch] files in the package.
+	cgoCPPFLAGS = append(cgoCPPFLAGS, "-I", tmpdir)
+
+	// _cgo_gotypes.go (displayed "C") contains the type definitions.
+	files = append(files, filepath.Join(tmpdir, "_cgo_gotypes.go"))
+	displayFiles = append(displayFiles, "C")
+	for _, fn := range bp.CgoFiles {
+		// "foo.cgo1.go" (displayed "foo.go") is the processed Go source.
+		f := cgoRe.ReplaceAllString(fn[:len(fn)-len("go")], "_")
+		files = append(files, filepath.Join(tmpdir, f+"cgo1.go"))
+		displayFiles = append(displayFiles, fn)
+	}
+
+	var cgoflags []string
+	if bp.Goroot && bp.ImportPath == "runtime/cgo" {
+		cgoflags = append(cgoflags, "-import_runtime_cgo=false")
+	}
+	if bp.Goroot && bp.ImportPath == "runtime/race" || bp.ImportPath == "runtime/cgo" {
+		cgoflags = append(cgoflags, "-import_syscall=false")
+	}
+
+	args := stringList(
+		"go", "tool", "cgo", "-objdir", tmpdir, cgoflags, "--",
+		cgoCPPFLAGS, cgoexeCFLAGS, bp.CgoFiles,
+	)
+	if false {
+		log.Printf("Running cgo for package %q: %s (dir=%s)", bp.ImportPath, args, pkgdir)
+	}
+	cmd := exec.Command(args[0], args[1:]...)
+	cmd.Dir = pkgdir
+	cmd.Stdout = os.Stderr
+	cmd.Stderr = os.Stderr
+	if err := cmd.Run(); err != nil {
+		return nil, nil, fmt.Errorf("cgo failed: %s: %s", args, err)
+	}
+
+	return files, displayFiles, nil
+}
+
+// -- unmodified from 'go build' ---------------------------------------
+
+// Return the flags to use when invoking the C or C++ compilers, or cgo.
+func cflags(p *build.Package, def bool) (cppflags, cflags, cxxflags, ldflags []string) {
+	var defaults string
+	if def {
+		defaults = "-g -O2"
+	}
+
+	cppflags = stringList(envList("CGO_CPPFLAGS", ""), p.CgoCPPFLAGS)
+	cflags = stringList(envList("CGO_CFLAGS", defaults), p.CgoCFLAGS)
+	cxxflags = stringList(envList("CGO_CXXFLAGS", defaults), p.CgoCXXFLAGS)
+	ldflags = stringList(envList("CGO_LDFLAGS", defaults), p.CgoLDFLAGS)
+	return
+}
+
+// envList returns the value of the given environment variable broken
+// into fields, using the default value when the variable is empty.
+func envList(key, def string) []string {
+	v := os.Getenv(key)
+	if v == "" {
+		v = def
+	}
+	return strings.Fields(v)
+}
+
+// stringList's arguments should be a sequence of string or []string values.
+// stringList flattens them into a single []string.
+func stringList(args ...interface{}) []string {
+	var x []string
+	for _, arg := range args {
+		switch arg := arg.(type) {
+		case []string:
+			x = append(x, arg...)
+		case string:
+			x = append(x, arg)
+		default:
+			panic("stringList: invalid argument")
+		}
+	}
+	return x
+}

Godeps/_workspace/src/golang.org/x/tools/go/loader/doc.go

@@ -0,0 +1,189 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package loader loads a complete Go program from source code, parsing
+// and type-checking the initial packages plus their transitive closure
+// of dependencies.  The ASTs and the derived facts are retained for
+// later use.
+//
+// THIS INTERFACE IS EXPERIMENTAL AND IS LIKELY TO CHANGE.
+//
+// The package defines two primary types: Config, which specifies a
+// set of initial packages to load and various other options; and
+// Program, which is the result of successfully loading the packages
+// specified by a configuration.
+//
+// The configuration can be set directly, but *Config provides various
+// convenience methods to simplify the common cases, each of which can
+// be called any number of times.  Finally, these are followed by a
+// call to Load() to actually load and type-check the program.
+//
+//      var conf loader.Config
+//
+//      // Use the command-line arguments to specify
+//      // a set of initial packages to load from source.
+//      // See FromArgsUsage for help.
+//      rest, err := conf.FromArgs(os.Args[1:], wantTests)
+//
+//      // Parse the specified files and create an ad hoc package with path "foo".
+//      // All files must have the same 'package' declaration.
+//      conf.CreateFromFilenames("foo", "foo.go", "bar.go")
+//
+//      // Create an ad hoc package with path "foo" from
+//      // the specified already-parsed files.
+//      // All ASTs must have the same 'package' declaration.
+//      conf.CreateFromFiles("foo", parsedFiles)
+//
+//      // Add "runtime" to the set of packages to be loaded.
+//      conf.Import("runtime")
+//
+//      // Adds "fmt" and "fmt_test" to the set of packages
+//      // to be loaded.  "fmt" will include *_test.go files.
+//      conf.ImportWithTests("fmt")
+//
+//      // Finally, load all the packages specified by the configuration.
+//      prog, err := conf.Load()
+//
+// See examples_test.go for examples of API usage.
+//
+//
+// CONCEPTS AND TERMINOLOGY
+//
+// An AD HOC package is one specified as a set of source files on the
+// command line.  In the simplest case, it may consist of a single file
+// such as $GOROOT/src/net/http/triv.go.
+//
+// EXTERNAL TEST packages are those comprised of a set of *_test.go
+// files all with the same 'package foo_test' declaration, all in the
+// same directory.  (go/build.Package calls these files XTestFiles.)
+//
+// An IMPORTABLE package is one that can be referred to by some import
+// spec.  The Path() of each importable package is unique within a
+// Program.
+//
+// ad hoc packages and external test packages are NON-IMPORTABLE.  The
+// Path() of an ad hoc package is inferred from the package
+// declarations of its files and is therefore not a unique package key.
+// For example, Config.CreatePkgs may specify two initial ad hoc
+// packages both called "main".
+//
+// An AUGMENTED package is an importable package P plus all the
+// *_test.go files with same 'package foo' declaration as P.
+// (go/build.Package calls these files TestFiles.)
+//
+// The INITIAL packages are those specified in the configuration.  A
+// DEPENDENCY is a package loaded to satisfy an import in an initial
+// package or another dependency.
+//
+package loader
+
+// IMPLEMENTATION NOTES
+//
+// 'go test', in-package test files, and import cycles
+// ---------------------------------------------------
+//
+// An external test package may depend upon members of the augmented
+// package that are not in the unaugmented package, such as functions
+// that expose internals.  (See bufio/export_test.go for an example.)
+// So, the loader must ensure that for each external test package
+// it loads, it also augments the corresponding non-test package.
+//
+// The import graph over n unaugmented packages must be acyclic; the
+// import graph over n-1 unaugmented packages plus one augmented
+// package must also be acyclic.  ('go test' relies on this.)  But the
+// import graph over n augmented packages may contain cycles.
+//
+// First, all the (unaugmented) non-test packages and their
+// dependencies are imported in the usual way; the loader reports an
+// error if it detects an import cycle.
+//
+// Then, each package P for which testing is desired is augmented by
+// the list P' of its in-package test files, by calling
+// (*types.Checker).Files.  This arrangement ensures that P' may
+// reference definitions within P, but P may not reference definitions
+// within P'.  Furthermore, P' may import any other package, including
+// ones that depend upon P, without an import cycle error.
+//
+// Consider two packages A and B, both of which have lists of
+// in-package test files we'll call A' and B', and which have the
+// following import graph edges:
+//    B  imports A
+//    B' imports A
+//    A' imports B
+// This last edge would be expected to create an error were it not
+// for the special type-checking discipline above.
+// Cycles of size greater than two are possible.  For example:
+//   compress/bzip2/bzip2_test.go (package bzip2)  imports "io/ioutil"
+//   io/ioutil/tempfile_test.go   (package ioutil) imports "regexp"
+//   regexp/exec_test.go          (package regexp) imports "compress/bzip2"
+//
+//
+// Concurrency
+// -----------
+//
+// Let us define the import dependency graph as follows.  Each node is a
+// list of files passed to (Checker).Files at once.  Many of these lists
+// are the production code of an importable Go package, so those nodes
+// are labelled by the package's import path.  The remaining nodes are
+// ad hoc packages and lists of in-package *_test.go files that augment
+// an importable package; those nodes have no label.
+//
+// The edges of the graph represent import statements appearing within a
+// file.  An edge connects a node (a list of files) to the node it
+// imports, which is importable and thus always labelled.
+//
+// Loading is controlled by this dependency graph.
+//
+// To reduce I/O latency, we start loading a package's dependencies
+// asynchronously as soon as we've parsed its files and enumerated its
+// imports (scanImports).  This performs a preorder traversal of the
+// import dependency graph.
+//
+// To exploit hardware parallelism, we type-check unrelated packages in
+// parallel, where "unrelated" means not ordered by the partial order of
+// the import dependency graph.
+//
+// We use a concurrency-safe blocking cache (importer.imported) to
+// record the results of type-checking, whether success or failure.  An
+// entry is created in this cache by startLoad the first time the
+// package is imported.  The first goroutine to request an entry becomes
+// responsible for completing the task and broadcasting completion to
+// subsequent requestors, which block until then.
+//
+// Type checking occurs in (parallel) postorder: we cannot type-check a
+// set of files until we have loaded and type-checked all of their
+// immediate dependencies (and thus all of their transitive
+// dependencies). If the input were guaranteed free of import cycles,
+// this would be trivial: we could simply wait for completion of the
+// dependencies and then invoke the typechecker.
+//
+// But as we saw in the 'go test' section above, some cycles in the
+// import graph over packages are actually legal, so long as the
+// cycle-forming edge originates in the in-package test files that
+// augment the package.  This explains why the nodes of the import
+// dependency graph are not packages, but lists of files: the unlabelled
+// nodes avoid the cycles.  Consider packages A and B where B imports A
+// and A's in-package tests AT import B.  The naively constructed import
+// graph over packages would contain a cycle (A+AT) --> B --> (A+AT) but
+// the graph over lists of files is AT --> B --> A, where AT is an
+// unlabelled node.
+//
+// Awaiting completion of the dependencies in a cyclic graph would
+// deadlock, so we must materialize the import dependency graph (as
+// importer.graph) and check whether each import edge forms a cycle.  If
+// x imports y, and the graph already contains a path from y to x, then
+// there is an import cycle, in which case the processing of x must not
+// wait for the completion of processing of y.
+//
+// When the type-checker makes a callback (doImport) to the loader for a
+// given import edge, there are two possible cases.  In the normal case,
+// the dependency has already been completely type-checked; doImport
+// does a cache lookup and returns it.  In the cyclic case, the entry in
+// the cache is still necessarily incomplete, indicating a cycle.  We
+// perform the cycle check again to obtain the error message, and return
+// the error.
+//
+// The result of using concurrency is about a 2.5x speedup for stdlib_test.
+
+// TODO(adonovan): overhaul the package documentation.

Godeps/_workspace/src/golang.org/x/tools/go/loader/example_test.go

@@ -0,0 +1,170 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package loader_test
+
+import (
+	"fmt"
+	"go/token"
+	"log"
+	"path/filepath"
+	"runtime"
+	"sort"
+
+	"golang.org/x/tools/go/loader"
+)
+
+func printProgram(prog *loader.Program) {
+	// Created packages are the initial packages specified by a call
+	// to CreateFromFilenames or CreateFromFiles.
+	var names []string
+	for _, info := range prog.Created {
+		names = append(names, info.Pkg.Path())
+	}
+	fmt.Printf("created: %s\n", names)
+
+	// Imported packages are the initial packages specified by a
+	// call to Import or ImportWithTests.
+	names = nil
+	for _, info := range prog.Imported {
+		names = append(names, info.Pkg.Path())
+	}
+	sort.Strings(names)
+	fmt.Printf("imported: %s\n", names)
+
+	// InitialPackages contains the union of created and imported.
+	names = nil
+	for _, info := range prog.InitialPackages() {
+		names = append(names, info.Pkg.Path())
+	}
+	sort.Strings(names)
+	fmt.Printf("initial: %s\n", names)
+
+	// AllPackages contains all initial packages and their dependencies.
+	names = nil
+	for pkg := range prog.AllPackages {
+		names = append(names, pkg.Path())
+	}
+	sort.Strings(names)
+	fmt.Printf("all: %s\n", names)
+}
+
+func printFilenames(fset *token.FileSet, info *loader.PackageInfo) {
+	var names []string
+	for _, f := range info.Files {
+		names = append(names, filepath.Base(fset.File(f.Pos()).Name()))
+	}
+	fmt.Printf("%s.Files: %s\n", info.Pkg.Path(), names)
+}
+
+// This example loads a set of packages and all of their dependencies
+// from a typical command-line.  FromArgs parses a command line and
+// makes calls to the other methods of Config shown in the examples that
+// follow.
+func ExampleConfig_FromArgs() {
+	args := []string{"mytool", "unicode/utf8", "errors", "runtime", "--", "foo", "bar"}
+	const wantTests = false
+
+	var conf loader.Config
+	rest, err := conf.FromArgs(args[1:], wantTests)
+	prog, err := conf.Load()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	fmt.Printf("rest: %s\n", rest)
+	printProgram(prog)
+	// Output:
+	// rest: [foo bar]
+	// created: []
+	// imported: [errors runtime unicode/utf8]
+	// initial: [errors runtime unicode/utf8]
+	// all: [errors runtime unicode/utf8]
+}
+
+// This example creates and type-checks a single package (without tests)
+// from a list of filenames, and loads all of its dependencies.
+func ExampleConfig_CreateFromFilenames() {
+	var conf loader.Config
+	filename := filepath.Join(runtime.GOROOT(), "src/container/heap/heap.go")
+	conf.CreateFromFilenames("container/heap", filename)
+	prog, err := conf.Load()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	printProgram(prog)
+	// Output:
+	// created: [container/heap]
+	// imported: []
+	// initial: [container/heap]
+	// all: [container/heap sort]
+}
+
+// In the examples below, for stability, the chosen packages are
+// relatively small, platform-independent, and low-level (and thus
+// infrequently changing).
+// The strconv package has internal and external tests.
+
+const hello = `package main
+
+import "fmt"
+
+func main() {
+	fmt.Println("Hello, world.")
+}
+`
+
+// This example creates and type-checks a package from a list of
+// already-parsed files, and loads all its dependencies.
+func ExampleConfig_CreateFromFiles() {
+	var conf loader.Config
+	f, err := conf.ParseFile("hello.go", hello)
+	if err != nil {
+		log.Fatal(err)
+	}
+	conf.CreateFromFiles("hello", f)
+	prog, err := conf.Load()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	printProgram(prog)
+	printFilenames(prog.Fset, prog.Package("strconv"))
+	// Output:
+	// created: [hello]
+	// imported: []
+	// initial: [hello]
+	// all: [errors fmt hello io math os reflect runtime strconv sync sync/atomic syscall time unicode/utf8]
+	// strconv.Files: [atob.go atof.go atoi.go decimal.go extfloat.go ftoa.go isprint.go itoa.go quote.go]
+}
+
+// This example imports three packages, including the tests for one of
+// them, and loads all their dependencies.
+func ExampleConfig_Import() {
+	// ImportWithTest("strconv") causes strconv to include
+	// internal_test.go, and creates an external test package,
+	// strconv_test.
+	// (Compare with the example of CreateFromFiles.)
+
+	var conf loader.Config
+	conf.Import("unicode/utf8")
+	conf.Import("errors")
+	conf.ImportWithTests("strconv")
+	prog, err := conf.Load()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	printProgram(prog)
+	printFilenames(prog.Fset, prog.Package("strconv"))
+	printFilenames(prog.Fset, prog.Package("strconv_test"))
+	// Output:
+	// created: [strconv_test]
+	// imported: [errors strconv unicode/utf8]
+	// initial: [errors strconv strconv_test unicode/utf8]
+	// all: [bufio bytes errors flag fmt io math math/rand os reflect runtime runtime/pprof sort strconv strconv_test strings sync sync/atomic syscall testing text/tabwriter time unicode unicode/utf8]
+	// strconv.Files: [atob.go atof.go atoi.go decimal.go extfloat.go ftoa.go isprint.go itoa.go quote.go internal_test.go]
+	// strconv_test.Files: [atob_test.go atof_test.go atoi_test.go decimal_test.go fp_test.go ftoa_test.go itoa_test.go quote_example_test.go quote_test.go strconv_test.go]
+}

Godeps/_workspace/src/golang.org/x/tools/go/loader/loader.go

@@ -0,0 +1,935 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package loader
+
+// See doc.go for package documentation and implementation notes.
+
+import (
+	"errors"
+	"fmt"
+	"go/ast"
+	"go/build"
+	"go/parser"
+	"go/token"
+	"os"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+
+	"golang.org/x/tools/go/ast/astutil"
+	"golang.org/x/tools/go/types"
+)
+
+const trace = false // show timing info for type-checking
+
+// Config specifies the configuration for loading a whole program from
+// Go source code.
+// The zero value for Config is a ready-to-use default configuration.
+type Config struct {
+	// Fset is the file set for the parser to use when loading the
+	// program.  If nil, it may be lazily initialized by any
+	// method of Config.
+	Fset *token.FileSet
+
+	// ParserMode specifies the mode to be used by the parser when
+	// loading source packages.
+	ParserMode parser.Mode
+
+	// TypeChecker contains options relating to the type checker.
+	//
+	// The supplied IgnoreFuncBodies is not used; the effective
+	// value comes from the TypeCheckFuncBodies func below.
+	// The supplied Import function is not used either.
+	TypeChecker types.Config
+
+	// TypeCheckFuncBodies is a predicate over package import
+	// paths.  A package for which the predicate is false will
+	// have its package-level declarations type checked, but not
+	// its function bodies; this can be used to quickly load
+	// dependencies from source.  If nil, all func bodies are type
+	// checked.
+	TypeCheckFuncBodies func(string) bool
+
+	// If Build is non-nil, it is used to locate source packages.
+	// Otherwise &build.Default is used.
+	//
+	// By default, cgo is invoked to preprocess Go files that
+	// import the fake package "C".  This behaviour can be
+	// disabled by setting CGO_ENABLED=0 in the environment prior
+	// to startup, or by setting Build.CgoEnabled=false.
+	Build *build.Context
+
+	// The current directory, used for resolving relative package
+	// references such as "./go/loader".  If empty, os.Getwd will be
+	// used instead.
+	Cwd string
+
+	// If DisplayPath is non-nil, it is used to transform each
+	// file name obtained from Build.Import().  This can be used
+	// to prevent a virtualized build.Config's file names from
+	// leaking into the user interface.
+	DisplayPath func(path string) string
+
+	// If AllowErrors is true, Load will return a Program even
+	// if some of the its packages contained I/O, parser or type
+	// errors; such errors are accessible via PackageInfo.Errors.  If
+	// false, Load will fail if any package had an error.
+	AllowErrors bool
+
+	// CreatePkgs specifies a list of non-importable initial
+	// packages to create.  The resulting packages will appear in
+	// the corresponding elements of the Program.Created slice.
+	CreatePkgs []PkgSpec
+
+	// ImportPkgs specifies a set of initial packages to load from
+	// source.  The map keys are package import paths, used to
+	// locate the package relative to $GOROOT.
+	//
+	// The map value indicates whether to load tests.  If true, Load
+	// will add and type-check two lists of files to the package:
+	// non-test files followed by in-package *_test.go files.  In
+	// addition, it will append the external test package (if any)
+	// to Program.Created.
+	ImportPkgs map[string]bool
+
+	// FindPackage is called during Load to create the build.Package
+	// for a given import path.  If nil, a default implementation
+	// based on ctxt.Import is used.  A client may use this hook to
+	// adapt to a proprietary build system that does not follow the
+	// "go build" layout conventions, for example.
+	//
+	// It must be safe to call concurrently from multiple goroutines.
+	FindPackage func(ctxt *build.Context, importPath string) (*build.Package, error)
+}
+
+// A PkgSpec specifies a non-importable package to be created by Load.
+// Files are processed first, but typically only one of Files and
+// Filenames is provided.  The path needn't be globally unique.
+//
+type PkgSpec struct {
+	Path      string      // import path ("" => use package declaration)
+	Files     []*ast.File // ASTs of already-parsed files
+	Filenames []string    // names of files to be parsed
+}
+
+// A Program is a Go program loaded from source as specified by a Config.
+type Program struct {
+	Fset *token.FileSet // the file set for this program
+
+	// Created[i] contains the initial package whose ASTs or
+	// filenames were supplied by Config.CreatePkgs[i], followed by
+	// the external test package, if any, of each package in
+	// Config.ImportPkgs ordered by ImportPath.
+	Created []*PackageInfo
+
+	// Imported contains the initially imported packages,
+	// as specified by Config.ImportPkgs.
+	Imported map[string]*PackageInfo
+
+	// AllPackages contains the PackageInfo of every package
+	// encountered by Load: all initial packages and all
+	// dependencies, including incomplete ones.
+	AllPackages map[*types.Package]*PackageInfo
+
+	// importMap is the canonical mapping of import paths to
+	// packages.  It contains all Imported initial packages, but not
+	// Created ones, and all imported dependencies.
+	importMap map[string]*types.Package
+}
+
+// PackageInfo holds the ASTs and facts derived by the type-checker
+// for a single package.
+//
+// Not mutated once exposed via the API.
+//
+type PackageInfo struct {
+	Pkg                   *types.Package
+	Importable            bool        // true if 'import "Pkg.Path()"' would resolve to this
+	TransitivelyErrorFree bool        // true if Pkg and all its dependencies are free of errors
+	Files                 []*ast.File // syntax trees for the package's files
+	Errors                []error     // non-nil if the package had errors
+	types.Info                        // type-checker deductions.
+
+	checker   *types.Checker // transient type-checker state
+	errorFunc func(error)
+}
+
+func (info *PackageInfo) String() string { return info.Pkg.Path() }
+
+func (info *PackageInfo) appendError(err error) {
+	if info.errorFunc != nil {
+		info.errorFunc(err)
+	} else {
+		fmt.Fprintln(os.Stderr, err)
+	}
+	info.Errors = append(info.Errors, err)
+}
+
+func (conf *Config) fset() *token.FileSet {
+	if conf.Fset == nil {
+		conf.Fset = token.NewFileSet()
+	}
+	return conf.Fset
+}
+
+// ParseFile is a convenience function (intended for testing) that invokes
+// the parser using the Config's FileSet, which is initialized if nil.
+//
+// src specifies the parser input as a string, []byte, or io.Reader, and
+// filename is its apparent name.  If src is nil, the contents of
+// filename are read from the file system.
+//
+func (conf *Config) ParseFile(filename string, src interface{}) (*ast.File, error) {
+	// TODO(adonovan): use conf.build() etc like parseFiles does.
+	return parser.ParseFile(conf.fset(), filename, src, conf.ParserMode)
+}
+
+// FromArgsUsage is a partial usage message that applications calling
+// FromArgs may wish to include in their -help output.
+const FromArgsUsage = `
+<args> is a list of arguments denoting a set of initial packages.
+It may take one of two forms:
+
+1. A list of *.go source files.
+
+   All of the specified files are loaded, parsed and type-checked
+   as a single package.  All the files must belong to the same directory.
+
+2. A list of import paths, each denoting a package.
+
+   The package's directory is found relative to the $GOROOT and
+   $GOPATH using similar logic to 'go build', and the *.go files in
+   that directory are loaded, parsed and type-checked as a single
+   package.
+
+   In addition, all *_test.go files in the directory are then loaded
+   and parsed.  Those files whose package declaration equals that of
+   the non-*_test.go files are included in the primary package.  Test
+   files whose package declaration ends with "_test" are type-checked
+   as another package, the 'external' test package, so that a single
+   import path may denote two packages.  (Whether this behaviour is
+   enabled is tool-specific, and may depend on additional flags.)
+
+A '--' argument terminates the list of packages.
+`
+
+// FromArgs interprets args as a set of initial packages to load from
+// source and updates the configuration.  It returns the list of
+// unconsumed arguments.
+//
+// It is intended for use in command-line interfaces that require a
+// set of initial packages to be specified; see FromArgsUsage message
+// for details.
+//
+// Only superficial errors are reported at this stage; errors dependent
+// on I/O are detected during Load.
+//
+func (conf *Config) FromArgs(args []string, xtest bool) ([]string, error) {
+	var rest []string
+	for i, arg := range args {
+		if arg == "--" {
+			rest = args[i+1:]
+			args = args[:i]
+			break // consume "--" and return the remaining args
+		}
+	}
+
+	if len(args) > 0 && strings.HasSuffix(args[0], ".go") {
+		// Assume args is a list of a *.go files
+		// denoting a single ad hoc package.
+		for _, arg := range args {
+			if !strings.HasSuffix(arg, ".go") {
+				return nil, fmt.Errorf("named files must be .go files: %s", arg)
+			}
+		}
+		conf.CreateFromFilenames("", args...)
+	} else {
+		// Assume args are directories each denoting a
+		// package and (perhaps) an external test, iff xtest.
+		for _, arg := range args {
+			if xtest {
+				conf.ImportWithTests(arg)
+			} else {
+				conf.Import(arg)
+			}
+		}
+	}
+
+	return rest, nil
+}
+
+// CreateFromFilenames is a convenience function that adds
+// a conf.CreatePkgs entry to create a package of the specified *.go
+// files.
+//
+func (conf *Config) CreateFromFilenames(path string, filenames ...string) {
+	conf.CreatePkgs = append(conf.CreatePkgs, PkgSpec{Path: path, Filenames: filenames})
+}
+
+// CreateFromFiles is a convenience function that adds a conf.CreatePkgs
+// entry to create package of the specified path and parsed files.
+//
+func (conf *Config) CreateFromFiles(path string, files ...*ast.File) {
+	conf.CreatePkgs = append(conf.CreatePkgs, PkgSpec{Path: path, Files: files})
+}
+
+// ImportWithTests is a convenience function that adds path to
+// ImportPkgs, the set of initial source packages located relative to
+// $GOPATH.  The package will be augmented by any *_test.go files in
+// its directory that contain a "package x" (not "package x_test")
+// declaration.
+//
+// In addition, if any *_test.go files contain a "package x_test"
+// declaration, an additional package comprising just those files will
+// be added to CreatePkgs.
+//
+func (conf *Config) ImportWithTests(path string) { conf.addImport(path, true) }
+
+// Import is a convenience function that adds path to ImportPkgs, the
+// set of initial packages that will be imported from source.
+//
+func (conf *Config) Import(path string) { conf.addImport(path, false) }
+
+func (conf *Config) addImport(path string, tests bool) {
+	if path == "C" || path == "unsafe" {
+		return // ignore; not a real package
+	}
+	if conf.ImportPkgs == nil {
+		conf.ImportPkgs = make(map[string]bool)
+	}
+	conf.ImportPkgs[path] = conf.ImportPkgs[path] || tests
+}
+
+// PathEnclosingInterval returns the PackageInfo and ast.Node that
+// contain source interval [start, end), and all the node's ancestors
+// up to the AST root.  It searches all ast.Files of all packages in prog.
+// exact is defined as for astutil.PathEnclosingInterval.
+//
+// The zero value is returned if not found.
+//
+func (prog *Program) PathEnclosingInterval(start, end token.Pos) (pkg *PackageInfo, path []ast.Node, exact bool) {
+	for _, info := range prog.AllPackages {
+		for _, f := range info.Files {
+			if f.Pos() == token.NoPos {
+				// This can happen if the parser saw
+				// too many errors and bailed out.
+				// (Use parser.AllErrors to prevent that.)
+				continue
+			}
+			if !tokenFileContainsPos(prog.Fset.File(f.Pos()), start) {
+				continue
+			}
+			if path, exact := astutil.PathEnclosingInterval(f, start, end); path != nil {
+				return info, path, exact
+			}
+		}
+	}
+	return nil, nil, false
+}
+
+// InitialPackages returns a new slice containing the set of initial
+// packages (Created + Imported) in unspecified order.
+//
+func (prog *Program) InitialPackages() []*PackageInfo {
+	infos := make([]*PackageInfo, 0, len(prog.Created)+len(prog.Imported))
+	infos = append(infos, prog.Created...)
+	for _, info := range prog.Imported {
+		infos = append(infos, info)
+	}
+	return infos
+}
+
+// Package returns the ASTs and results of type checking for the
+// specified package.
+func (prog *Program) Package(path string) *PackageInfo {
+	if info, ok := prog.AllPackages[prog.importMap[path]]; ok {
+		return info
+	}
+	for _, info := range prog.Created {
+		if path == info.Pkg.Path() {
+			return info
+		}
+	}
+	return nil
+}
+
+// ---------- Implementation ----------
+
+// importer holds the working state of the algorithm.
+type importer struct {
+	conf  *Config   // the client configuration
+	start time.Time // for logging
+
+	progMu sync.Mutex // guards prog
+	prog   *Program   // the resulting program
+
+	importedMu sync.Mutex             // guards imported
+	imported   map[string]*importInfo // all imported packages (incl. failures) by import path
+
+	// import dependency graph: graph[x][y] => x imports y
+	//
+	// Since non-importable packages cannot be cyclic, we ignore
+	// their imports, thus we only need the subgraph over importable
+	// packages.  Nodes are identified by their import paths.
+	graphMu sync.Mutex
+	graph   map[string]map[string]bool
+}
+
+// importInfo tracks the success or failure of a single import.
+//
+// Upon completion, exactly one of info and err is non-nil:
+// info on successful creation of a package, err otherwise.
+// A successful package may still contain type errors.
+//
+type importInfo struct {
+	path     string       // import path
+	mu       sync.Mutex   // guards the following fields prior to completion
+	info     *PackageInfo // results of typechecking (including errors)
+	err      error        // reason for failure to create a package
+	complete sync.Cond    // complete condition is that one of info, err is non-nil.
+}
+
+// awaitCompletion blocks until ii is complete,
+// i.e. the info and err fields are safe to inspect without a lock.
+// It is concurrency-safe and idempotent.
+func (ii *importInfo) awaitCompletion() {
+	ii.mu.Lock()
+	for ii.info == nil && ii.err == nil {
+		ii.complete.Wait()
+	}
+	ii.mu.Unlock()
+}
+
+// Complete marks ii as complete.
+// Its info and err fields will not be subsequently updated.
+func (ii *importInfo) Complete(info *PackageInfo, err error) {
+	ii.mu.Lock()
+	ii.info = info
+	ii.err = err
+	ii.complete.Broadcast()
+	ii.mu.Unlock()
+}
+
+// Load creates the initial packages specified by conf.{Create,Import}Pkgs,
+// loading their dependencies packages as needed.
+//
+// On success, Load returns a Program containing a PackageInfo for
+// each package.  On failure, it returns an error.
+//
+// If AllowErrors is true, Load will return a Program even if some
+// packages contained I/O, parser or type errors, or if dependencies
+// were missing.  (Such errors are accessible via PackageInfo.Errors.  If
+// false, Load will fail if any package had an error.
+//
+// It is an error if no packages were loaded.
+//
+func (conf *Config) Load() (*Program, error) {
+	// Create a simple default error handler for parse/type errors.
+	if conf.TypeChecker.Error == nil {
+		conf.TypeChecker.Error = func(e error) { fmt.Fprintln(os.Stderr, e) }
+	}
+
+	// Set default working directory for relative package references.
+	if conf.Cwd == "" {
+		var err error
+		conf.Cwd, err = os.Getwd()
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	// Install default FindPackage hook using go/build logic.
+	if conf.FindPackage == nil {
+		conf.FindPackage = func(ctxt *build.Context, path string) (*build.Package, error) {
+			// TODO(adonovan): cache calls to build.Import
+			// so we don't do it three times per test package.
+			bp, err := ctxt.Import(path, conf.Cwd, 0)
+			if _, ok := err.(*build.NoGoError); ok {
+				return bp, nil // empty directory is not an error
+			}
+			return bp, err
+		}
+	}
+
+	prog := &Program{
+		Fset:        conf.fset(),
+		Imported:    make(map[string]*PackageInfo),
+		importMap:   make(map[string]*types.Package),
+		AllPackages: make(map[*types.Package]*PackageInfo),
+	}
+
+	imp := importer{
+		conf:     conf,
+		prog:     prog,
+		imported: make(map[string]*importInfo),
+		start:    time.Now(),
+		graph:    make(map[string]map[string]bool),
+	}
+
+	// -- loading proper (concurrent phase) --------------------------------
+
+	var errpkgs []string // packages that contained errors
+
+	// Load the initially imported packages and their dependencies,
+	// in parallel.
+	for _, ii := range imp.loadAll("", conf.ImportPkgs) {
+		if ii.err != nil {
+			conf.TypeChecker.Error(ii.err) // failed to create package
+			errpkgs = append(errpkgs, ii.path)
+			continue
+		}
+		prog.Imported[ii.info.Pkg.Path()] = ii.info
+	}
+
+	// Augment the designated initial packages by their tests.
+	// Dependencies are loaded in parallel.
+	var xtestPkgs []*build.Package
+	for path, augment := range conf.ImportPkgs {
+		if !augment {
+			continue
+		}
+
+		bp, err := conf.FindPackage(conf.build(), path)
+		if err != nil {
+			// Package not found, or can't even parse package declaration.
+			// Already reported by previous loop; ignore it.
+			continue
+		}
+
+		// Needs external test package?
+		if len(bp.XTestGoFiles) > 0 {
+			xtestPkgs = append(xtestPkgs, bp)
+		}
+
+		imp.importedMu.Lock()           // (unnecessary, we're sequential here)
+		info := imp.imported[path].info // must be non-nil, see above
+		imp.importedMu.Unlock()
+
+		// Parse the in-package test files.
+		files, errs := imp.conf.parsePackageFiles(bp, 't')
+		for _, err := range errs {
+			info.appendError(err)
+		}
+
+		// The test files augmenting package P cannot be imported,
+		// but may import packages that import P,
+		// so we must disable the cycle check.
+		imp.addFiles(info, files, false)
+	}
+
+	createPkg := func(path string, files []*ast.File, errs []error) {
+		info := imp.newPackageInfo(path)
+		for _, err := range errs {
+			info.appendError(err)
+		}
+
+		// Ad hoc packages are non-importable,
+		// so no cycle check is needed.
+		// addFiles loads dependencies in parallel.
+		imp.addFiles(info, files, false)
+		prog.Created = append(prog.Created, info)
+	}
+
+	// Create packages specified by conf.CreatePkgs.
+	for _, cp := range conf.CreatePkgs {
+		files, errs := parseFiles(conf.fset(), conf.build(), nil, ".", cp.Filenames, conf.ParserMode)
+		files = append(files, cp.Files...)
+
+		path := cp.Path
+		if path == "" {
+			if len(files) > 0 {
+				path = files[0].Name.Name
+			} else {
+				path = "(unnamed)"
+			}
+		}
+		createPkg(path, files, errs)
+	}
+
+	// Create external test packages.
+	sort.Sort(byImportPath(xtestPkgs))
+	for _, bp := range xtestPkgs {
+		files, errs := imp.conf.parsePackageFiles(bp, 'x')
+		createPkg(bp.ImportPath+"_test", files, errs)
+	}
+
+	// -- finishing up (sequential) ----------------------------------------
+
+	if len(prog.Imported)+len(prog.Created) == 0 {
+		return nil, errors.New("no initial packages were loaded")
+	}
+
+	// Create infos for indirectly imported packages.
+	// e.g. incomplete packages without syntax, loaded from export data.
+	for _, obj := range prog.importMap {
+		info := prog.AllPackages[obj]
+		if info == nil {
+			prog.AllPackages[obj] = &PackageInfo{Pkg: obj, Importable: true}
+		} else {
+			// finished
+			info.checker = nil
+			info.errorFunc = nil
+		}
+	}
+
+	if !conf.AllowErrors {
+		// Report errors in indirectly imported packages.
+		for _, info := range prog.AllPackages {
+			if len(info.Errors) > 0 {
+				errpkgs = append(errpkgs, info.Pkg.Path())
+			}
+		}
+		if errpkgs != nil {
+			var more string
+			if len(errpkgs) > 3 {
+				more = fmt.Sprintf(" and %d more", len(errpkgs)-3)
+				errpkgs = errpkgs[:3]
+			}
+			return nil, fmt.Errorf("couldn't load packages due to errors: %s%s",
+				strings.Join(errpkgs, ", "), more)
+		}
+	}
+
+	markErrorFreePackages(prog.AllPackages)
+
+	return prog, nil
+}
+
+type byImportPath []*build.Package
+
+func (b byImportPath) Len() int           { return len(b) }
+func (b byImportPath) Less(i, j int) bool { return b[i].ImportPath < b[j].ImportPath }
+func (b byImportPath) Swap(i, j int)      { b[i], b[j] = b[j], b[i] }
+
+// markErrorFreePackages sets the TransitivelyErrorFree flag on all
+// applicable packages.
+func markErrorFreePackages(allPackages map[*types.Package]*PackageInfo) {
+	// Build the transpose of the import graph.
+	importedBy := make(map[*types.Package]map[*types.Package]bool)
+	for P := range allPackages {
+		for _, Q := range P.Imports() {
+			clients, ok := importedBy[Q]
+			if !ok {
+				clients = make(map[*types.Package]bool)
+				importedBy[Q] = clients
+			}
+			clients[P] = true
+		}
+	}
+
+	// Find all packages reachable from some error package.
+	reachable := make(map[*types.Package]bool)
+	var visit func(*types.Package)
+	visit = func(p *types.Package) {
+		if !reachable[p] {
+			reachable[p] = true
+			for q := range importedBy[p] {
+				visit(q)
+			}
+		}
+	}
+	for _, info := range allPackages {
+		if len(info.Errors) > 0 {
+			visit(info.Pkg)
+		}
+	}
+
+	// Mark the others as "transitively error-free".
+	for _, info := range allPackages {
+		if !reachable[info.Pkg] {
+			info.TransitivelyErrorFree = true
+		}
+	}
+}
+
+// build returns the effective build context.
+func (conf *Config) build() *build.Context {
+	if conf.Build != nil {
+		return conf.Build
+	}
+	return &build.Default
+}
+
+// parsePackageFiles enumerates the files belonging to package path,
+// then loads, parses and returns them, plus a list of I/O or parse
+// errors that were encountered.
+//
+// 'which' indicates which files to include:
+//    'g': include non-test *.go source files (GoFiles + processed CgoFiles)
+//    't': include in-package *_test.go source files (TestGoFiles)
+//    'x': include external *_test.go source files. (XTestGoFiles)
+//
+func (conf *Config) parsePackageFiles(bp *build.Package, which rune) ([]*ast.File, []error) {
+	var filenames []string
+	switch which {
+	case 'g':
+		filenames = bp.GoFiles
+	case 't':
+		filenames = bp.TestGoFiles
+	case 'x':
+		filenames = bp.XTestGoFiles
+	default:
+		panic(which)
+	}
+
+	files, errs := parseFiles(conf.fset(), conf.build(), conf.DisplayPath, bp.Dir, filenames, conf.ParserMode)
+
+	// Preprocess CgoFiles and parse the outputs (sequentially).
+	if which == 'g' && bp.CgoFiles != nil {
+		cgofiles, err := processCgoFiles(bp, conf.fset(), conf.DisplayPath, conf.ParserMode)
+		if err != nil {
+			errs = append(errs, err)
+		} else {
+			files = append(files, cgofiles...)
+		}
+	}
+
+	return files, errs
+}
+
+// doImport imports the package denoted by path.
+// It implements the types.Importer signature.
+//
+// imports is the type-checker's package canonicalization map.
+//
+// It returns an error if a package could not be created
+// (e.g. go/build or parse error), but type errors are reported via
+// the types.Config.Error callback (the first of which is also saved
+// in the package's PackageInfo).
+//
+// Idempotent.
+//
+func (imp *importer) doImport(from *PackageInfo, to string) (*types.Package, error) {
+	// Package unsafe is handled specially, and has no PackageInfo.
+	// TODO(adonovan): move this check into go/types?
+	if to == "unsafe" {
+		return types.Unsafe, nil
+	}
+	if to == "C" {
+		// This should be unreachable, but ad hoc packages are
+		// not currently subject to cgo preprocessing.
+		// See https://github.com/golang/go/issues/11627.
+		return nil, fmt.Errorf(`the loader doesn't cgo-process ad hoc packages like %q; see Go issue 11627`,
+			from.Pkg.Path())
+	}
+
+	imp.importedMu.Lock()
+	ii := imp.imported[to]
+	imp.importedMu.Unlock()
+	if ii == nil {
+		panic("internal error: unexpected import: " + to)
+	}
+	if ii.err != nil {
+		return nil, ii.err
+	}
+	if ii.info != nil {
+		return ii.info.Pkg, nil
+	}
+
+	// Import of incomplete package: this indicates a cycle.
+	fromPath := from.Pkg.Path()
+	if cycle := imp.findPath(to, fromPath); cycle != nil {
+		cycle = append([]string{fromPath}, cycle...)
+		return nil, fmt.Errorf("import cycle: %s", strings.Join(cycle, " -> "))
+	}
+
+	panic("internal error: import of incomplete (yet acyclic) package: " + fromPath)
+}
+
+// loadAll loads, parses, and type-checks the specified packages in
+// parallel and returns their completed importInfos in unspecified order.
+//
+// fromPath is the import path of the importing package, if it is
+// importable, "" otherwise.  It is used for cycle detection.
+//
+func (imp *importer) loadAll(fromPath string, paths map[string]bool) []*importInfo {
+	result := make([]*importInfo, 0, len(paths))
+	for path := range paths {
+		result = append(result, imp.startLoad(path))
+	}
+
+	if fromPath != "" {
+		// We're loading a set of imports.
+		//
+		// We must record graph edges from the importing package
+		// to its dependencies, and check for cycles.
+		imp.graphMu.Lock()
+		deps, ok := imp.graph[fromPath]
+		if !ok {
+			deps = make(map[string]bool)
+			imp.graph[fromPath] = deps
+		}
+		for path := range paths {
+			deps[path] = true
+		}
+		imp.graphMu.Unlock()
+	}
+
+	for _, ii := range result {
+		if fromPath != "" {
+			if cycle := imp.findPath(ii.path, fromPath); cycle != nil {
+				// Cycle-forming import: we must not await its
+				// completion since it would deadlock.
+				//
+				// We don't record the error in ii since
+				// the error is really associated with the
+				// cycle-forming edge, not the package itself.
+				// (Also it would complicate the
+				// invariants of importPath completion.)
+				if trace {
+					fmt.Fprintln(os.Stderr, "import cycle: %q", cycle)
+				}
+				continue
+			}
+		}
+		ii.awaitCompletion()
+
+	}
+	return result
+}
+
+// findPath returns an arbitrary path from 'from' to 'to' in the import
+// graph, or nil if there was none.
+func (imp *importer) findPath(from, to string) []string {
+	imp.graphMu.Lock()
+	defer imp.graphMu.Unlock()
+
+	seen := make(map[string]bool)
+	var search func(stack []string, importPath string) []string
+	search = func(stack []string, importPath string) []string {
+		if !seen[importPath] {
+			seen[importPath] = true
+			stack = append(stack, importPath)
+			if importPath == to {
+				return stack
+			}
+			for x := range imp.graph[importPath] {
+				if p := search(stack, x); p != nil {
+					return p
+				}
+			}
+		}
+		return nil
+	}
+	return search(make([]string, 0, 20), from)
+}
+
+// startLoad initiates the loading, parsing and type-checking of the
+// specified package and its dependencies, if it has not already begun.
+//
+// It returns an importInfo, not necessarily in a completed state.  The
+// caller must call awaitCompletion() before accessing its info and err
+// fields.
+//
+// startLoad is concurrency-safe and idempotent.
+//
+// Precondition: path != "unsafe".
+//
+func (imp *importer) startLoad(path string) *importInfo {
+	imp.importedMu.Lock()
+	ii, ok := imp.imported[path]
+	if !ok {
+		ii = &importInfo{path: path}
+		ii.complete.L = &ii.mu
+		imp.imported[path] = ii
+		go func() {
+			ii.Complete(imp.load(path))
+		}()
+	}
+	imp.importedMu.Unlock()
+
+	return ii
+}
+
+// load implements package loading by parsing Go source files
+// located by go/build.
+//
+func (imp *importer) load(path string) (*PackageInfo, error) {
+	bp, err := imp.conf.FindPackage(imp.conf.build(), path)
+	if err != nil {
+		return nil, err // package not found
+	}
+	info := imp.newPackageInfo(bp.ImportPath)
+	info.Importable = true
+	files, errs := imp.conf.parsePackageFiles(bp, 'g')
+	for _, err := range errs {
+		info.appendError(err)
+	}
+
+	imp.addFiles(info, files, true)
+
+	imp.progMu.Lock()
+	imp.prog.importMap[path] = info.Pkg
+	imp.progMu.Unlock()
+
+	return info, nil
+}
+
+// addFiles adds and type-checks the specified files to info, loading
+// their dependencies if needed.  The order of files determines the
+// package initialization order.  It may be called multiple times on the
+// same package.  Errors are appended to the info.Errors field.
+//
+// cycleCheck determines whether the imports within files create
+// dependency edges that should be checked for potential cycles.
+//
+func (imp *importer) addFiles(info *PackageInfo, files []*ast.File, cycleCheck bool) {
+	info.Files = append(info.Files, files...)
+
+	// Ensure the dependencies are loaded, in parallel.
+	var fromPath string
+	if cycleCheck {
+		fromPath = info.Pkg.Path()
+	}
+	imp.loadAll(fromPath, scanImports(files))
+
+	if trace {
+		fmt.Fprintf(os.Stderr, "%s: start %q (%d)\n",
+			time.Since(imp.start), info.Pkg.Path(), len(files))
+	}
+
+	// Ignore the returned (first) error since we
+	// already collect them all in the PackageInfo.
+	info.checker.Files(files)
+
+	if trace {
+		fmt.Fprintf(os.Stderr, "%s: stop %q\n",
+			time.Since(imp.start), info.Pkg.Path())
+	}
+}
+
+func (imp *importer) newPackageInfo(path string) *PackageInfo {
+	pkg := types.NewPackage(path, "")
+	info := &PackageInfo{
+		Pkg: pkg,
+		Info: types.Info{
+			Types:      make(map[ast.Expr]types.TypeAndValue),
+			Defs:       make(map[*ast.Ident]types.Object),
+			Uses:       make(map[*ast.Ident]types.Object),
+			Implicits:  make(map[ast.Node]types.Object),
+			Scopes:     make(map[ast.Node]*types.Scope),
+			Selections: make(map[*ast.SelectorExpr]*types.Selection),
+		},
+		errorFunc: imp.conf.TypeChecker.Error,
+	}
+
+	// Copy the types.Config so we can vary it across PackageInfos.
+	tc := imp.conf.TypeChecker
+	tc.IgnoreFuncBodies = false
+	if f := imp.conf.TypeCheckFuncBodies; f != nil {
+		tc.IgnoreFuncBodies = !f(path)
+	}
+	tc.Import = func(_ map[string]*types.Package, to string) (*types.Package, error) {
+		return imp.doImport(info, to)
+	}
+	tc.Error = info.appendError // appendError wraps the user's Error function
+
+	info.checker = types.NewChecker(&tc, imp.conf.fset(), pkg, &info.Info)
+	imp.progMu.Lock()
+	imp.prog.AllPackages[pkg] = info
+	imp.progMu.Unlock()
+	return info
+}

Godeps/_workspace/src/golang.org/x/tools/go/loader/loader_test.go

@@ -0,0 +1,669 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package loader_test
+
+import (
+	"fmt"
+	"go/build"
+	"reflect"
+	"sort"
+	"strings"
+	"sync"
+	"testing"
+
+	"golang.org/x/tools/go/buildutil"
+	"golang.org/x/tools/go/loader"
+)
+
+// TestFromArgs checks that conf.FromArgs populates conf correctly.
+// It does no I/O.
+func TestFromArgs(t *testing.T) {
+	type result struct {
+		Err        string
+		Rest       []string
+		ImportPkgs map[string]bool
+		CreatePkgs []loader.PkgSpec
+	}
+	for _, test := range []struct {
+		args  []string
+		tests bool
+		want  result
+	}{
+		// Mix of existing and non-existent packages.
+		{
+			args: []string{"nosuchpkg", "errors"},
+			want: result{
+				ImportPkgs: map[string]bool{"errors": false, "nosuchpkg": false},
+			},
+		},
+		// Same, with -test flag.
+		{
+			args:  []string{"nosuchpkg", "errors"},
+			tests: true,
+			want: result{
+				ImportPkgs: map[string]bool{"errors": true, "nosuchpkg": true},
+			},
+		},
+		// Surplus arguments.
+		{
+			args: []string{"fmt", "errors", "--", "surplus"},
+			want: result{
+				Rest:       []string{"surplus"},
+				ImportPkgs: map[string]bool{"errors": false, "fmt": false},
+			},
+		},
+		// Ad hoc package specified as *.go files.
+		{
+			args: []string{"foo.go", "bar.go"},
+			want: result{CreatePkgs: []loader.PkgSpec{{
+				Filenames: []string{"foo.go", "bar.go"},
+			}}},
+		},
+		// Mixture of *.go and import paths.
+		{
+			args: []string{"foo.go", "fmt"},
+			want: result{
+				Err: "named files must be .go files: fmt",
+			},
+		},
+	} {
+		var conf loader.Config
+		rest, err := conf.FromArgs(test.args, test.tests)
+		got := result{
+			Rest:       rest,
+			ImportPkgs: conf.ImportPkgs,
+			CreatePkgs: conf.CreatePkgs,
+		}
+		if err != nil {
+			got.Err = err.Error()
+		}
+		if !reflect.DeepEqual(got, test.want) {
+			t.Errorf("FromArgs(%q) = %+v, want %+v", test.args, got, test.want)
+		}
+	}
+}
+
+func TestLoad_NoInitialPackages(t *testing.T) {
+	var conf loader.Config
+
+	const wantErr = "no initial packages were loaded"
+
+	prog, err := conf.Load()
+	if err == nil {
+		t.Errorf("Load succeeded unexpectedly, want %q", wantErr)
+	} else if err.Error() != wantErr {
+		t.Errorf("Load failed with wrong error %q, want %q", err, wantErr)
+	}
+	if prog != nil {
+		t.Errorf("Load unexpectedly returned a Program")
+	}
+}
+
+func TestLoad_MissingInitialPackage(t *testing.T) {
+	var conf loader.Config
+	conf.Import("nosuchpkg")
+	conf.Import("errors")
+
+	const wantErr = "couldn't load packages due to errors: nosuchpkg"
+
+	prog, err := conf.Load()
+	if err == nil {
+		t.Errorf("Load succeeded unexpectedly, want %q", wantErr)
+	} else if err.Error() != wantErr {
+		t.Errorf("Load failed with wrong error %q, want %q", err, wantErr)
+	}
+	if prog != nil {
+		t.Errorf("Load unexpectedly returned a Program")
+	}
+}
+
+func TestLoad_MissingInitialPackage_AllowErrors(t *testing.T) {
+	var conf loader.Config
+	conf.AllowErrors = true
+	conf.Import("nosuchpkg")
+	conf.ImportWithTests("errors")
+
+	prog, err := conf.Load()
+	if err != nil {
+		t.Errorf("Load failed unexpectedly: %v", err)
+	}
+	if prog == nil {
+		t.Fatalf("Load returned a nil Program")
+	}
+	if got, want := created(prog), "errors_test"; got != want {
+		t.Errorf("Created = %s, want %s", got, want)
+	}
+	if got, want := imported(prog), "errors"; got != want {
+		t.Errorf("Imported = %s, want %s", got, want)
+	}
+}
+
+func TestCreateUnnamedPackage(t *testing.T) {
+	var conf loader.Config
+	conf.CreateFromFilenames("")
+	prog, err := conf.Load()
+	if err != nil {
+		t.Fatalf("Load failed: %v", err)
+	}
+	if got, want := fmt.Sprint(prog.InitialPackages()), "[(unnamed)]"; got != want {
+		t.Errorf("InitialPackages = %s, want %s", got, want)
+	}
+}
+
+func TestLoad_MissingFileInCreatedPackage(t *testing.T) {
+	var conf loader.Config
+	conf.CreateFromFilenames("", "missing.go")
+
+	const wantErr = "couldn't load packages due to errors: (unnamed)"
+
+	prog, err := conf.Load()
+	if prog != nil {
+		t.Errorf("Load unexpectedly returned a Program")
+	}
+	if err == nil {
+		t.Fatalf("Load succeeded unexpectedly, want %q", wantErr)
+	}
+	if err.Error() != wantErr {
+		t.Fatalf("Load failed with wrong error %q, want %q", err, wantErr)
+	}
+}
+
+func TestLoad_MissingFileInCreatedPackage_AllowErrors(t *testing.T) {
+	conf := loader.Config{AllowErrors: true}
+	conf.CreateFromFilenames("", "missing.go")
+
+	prog, err := conf.Load()
+	if err != nil {
+		t.Errorf("Load failed: %v", err)
+	}
+	if got, want := fmt.Sprint(prog.InitialPackages()), "[(unnamed)]"; got != want {
+		t.Fatalf("InitialPackages = %s, want %s", got, want)
+	}
+}
+
+func TestLoad_ParseError(t *testing.T) {
+	var conf loader.Config
+	conf.CreateFromFilenames("badpkg", "testdata/badpkgdecl.go")
+
+	const wantErr = "couldn't load packages due to errors: badpkg"
+
+	prog, err := conf.Load()
+	if prog != nil {
+		t.Errorf("Load unexpectedly returned a Program")
+	}
+	if err == nil {
+		t.Fatalf("Load succeeded unexpectedly, want %q", wantErr)
+	}
+	if err.Error() != wantErr {
+		t.Fatalf("Load failed with wrong error %q, want %q", err, wantErr)
+	}
+}
+
+func TestLoad_ParseError_AllowErrors(t *testing.T) {
+	var conf loader.Config
+	conf.AllowErrors = true
+	conf.CreateFromFilenames("badpkg", "testdata/badpkgdecl.go")
+
+	prog, err := conf.Load()
+	if err != nil {
+		t.Errorf("Load failed unexpectedly: %v", err)
+	}
+	if prog == nil {
+		t.Fatalf("Load returned a nil Program")
+	}
+	if got, want := created(prog), "badpkg"; got != want {
+		t.Errorf("Created = %s, want %s", got, want)
+	}
+
+	badpkg := prog.Created[0]
+	if len(badpkg.Files) != 1 {
+		t.Errorf("badpkg has %d files, want 1", len(badpkg.Files))
+	}
+	wantErr := "testdata/badpkgdecl.go:1:34: expected 'package', found 'EOF'"
+	if !hasError(badpkg.Errors, wantErr) {
+		t.Errorf("badpkg.Errors = %v, want %s", badpkg.Errors, wantErr)
+	}
+}
+
+func TestLoad_FromSource_Success(t *testing.T) {
+	var conf loader.Config
+	conf.CreateFromFilenames("P", "testdata/a.go", "testdata/b.go")
+
+	prog, err := conf.Load()
+	if err != nil {
+		t.Errorf("Load failed unexpectedly: %v", err)
+	}
+	if prog == nil {
+		t.Fatalf("Load returned a nil Program")
+	}
+	if got, want := created(prog), "P"; got != want {
+		t.Errorf("Created = %s, want %s", got, want)
+	}
+}
+
+func TestLoad_FromImports_Success(t *testing.T) {
+	var conf loader.Config
+	conf.ImportWithTests("fmt")
+	conf.ImportWithTests("errors")
+
+	prog, err := conf.Load()
+	if err != nil {
+		t.Errorf("Load failed unexpectedly: %v", err)
+	}
+	if prog == nil {
+		t.Fatalf("Load returned a nil Program")
+	}
+	if got, want := created(prog), "errors_test fmt_test"; got != want {
+		t.Errorf("Created = %q, want %s", got, want)
+	}
+	if got, want := imported(prog), "errors fmt"; got != want {
+		t.Errorf("Imported = %s, want %s", got, want)
+	}
+	// Check set of transitive packages.
+	// There are >30 and the set may grow over time, so only check a few.
+	want := map[string]bool{
+		"strings": true,
+		"time":    true,
+		"runtime": true,
+		"testing": true,
+		"unicode": true,
+	}
+	for _, path := range all(prog) {
+		delete(want, path)
+	}
+	if len(want) > 0 {
+		t.Errorf("AllPackages is missing these keys: %q", keys(want))
+	}
+}
+
+func TestLoad_MissingIndirectImport(t *testing.T) {
+	pkgs := map[string]string{
+		"a": `package a; import _ "b"`,
+		"b": `package b; import _ "c"`,
+	}
+	conf := loader.Config{Build: fakeContext(pkgs)}
+	conf.Import("a")
+
+	const wantErr = "couldn't load packages due to errors: b"
+
+	prog, err := conf.Load()
+	if err == nil {
+		t.Errorf("Load succeeded unexpectedly, want %q", wantErr)
+	} else if err.Error() != wantErr {
+		t.Errorf("Load failed with wrong error %q, want %q", err, wantErr)
+	}
+	if prog != nil {
+		t.Errorf("Load unexpectedly returned a Program")
+	}
+}
+
+func TestLoad_BadDependency_AllowErrors(t *testing.T) {
+	for _, test := range []struct {
+		descr    string
+		pkgs     map[string]string
+		wantPkgs string
+	}{
+
+		{
+			descr: "missing dependency",
+			pkgs: map[string]string{
+				"a": `package a; import _ "b"`,
+				"b": `package b; import _ "c"`,
+			},
+			wantPkgs: "a b",
+		},
+		{
+			descr: "bad package decl in dependency",
+			pkgs: map[string]string{
+				"a": `package a; import _ "b"`,
+				"b": `package b; import _ "c"`,
+				"c": `package`,
+			},
+			wantPkgs: "a b",
+		},
+		{
+			descr: "parse error in dependency",
+			pkgs: map[string]string{
+				"a": `package a; import _ "b"`,
+				"b": `package b; import _ "c"`,
+				"c": `package c; var x = `,
+			},
+			wantPkgs: "a b c",
+		},
+	} {
+		conf := loader.Config{
+			AllowErrors: true,
+			Build:       fakeContext(test.pkgs),
+		}
+		conf.Import("a")
+
+		prog, err := conf.Load()
+		if err != nil {
+			t.Errorf("%s: Load failed unexpectedly: %v", test.descr, err)
+		}
+		if prog == nil {
+			t.Fatalf("%s: Load returned a nil Program", test.descr)
+		}
+
+		if got, want := imported(prog), "a"; got != want {
+			t.Errorf("%s: Imported = %s, want %s", test.descr, got, want)
+		}
+		if got := all(prog); strings.Join(got, " ") != test.wantPkgs {
+			t.Errorf("%s: AllPackages = %s, want %s", test.descr, got, test.wantPkgs)
+		}
+	}
+}
+
+func TestCwd(t *testing.T) {
+	ctxt := fakeContext(map[string]string{"one/two/three": `package three`})
+	for _, test := range []struct {
+		cwd, arg, want string
+	}{
+		{cwd: "/go/src/one", arg: "./two/three", want: "one/two/three"},
+		{cwd: "/go/src/one", arg: "../one/two/three", want: "one/two/three"},
+		{cwd: "/go/src/one", arg: "one/two/three", want: "one/two/three"},
+		{cwd: "/go/src/one/two/three", arg: ".", want: "one/two/three"},
+		{cwd: "/go/src/one", arg: "two/three", want: ""},
+	} {
+		conf := loader.Config{
+			Cwd:   test.cwd,
+			Build: ctxt,
+		}
+		conf.Import(test.arg)
+
+		var got string
+		prog, err := conf.Load()
+		if prog != nil {
+			got = imported(prog)
+		}
+		if got != test.want {
+			t.Errorf("Load(%s) from %s: Imported = %s, want %s",
+				test.arg, test.cwd, got, test.want)
+			if err != nil {
+				t.Errorf("Load failed: %v", err)
+			}
+		}
+	}
+}
+
+// TODO(adonovan): more Load tests:
+//
+// failures:
+// - to parse package decl of *_test.go files
+// - to parse package decl of external *_test.go files
+// - to parse whole of *_test.go files
+// - to parse whole of external *_test.go files
+// - to open a *.go file during import scanning
+// - to import from binary
+
+// features:
+// - InitialPackages
+// - PackageCreated hook
+// - TypeCheckFuncBodies hook
+
+func TestTransitivelyErrorFreeFlag(t *testing.T) {
+	// Create an minimal custom build.Context
+	// that fakes the following packages:
+	//
+	// a --> b --> c!   c has an error
+	//   \              d and e are transitively error-free.
+	//    e --> d
+	//
+	// Each package [a-e] consists of one file, x.go.
+	pkgs := map[string]string{
+		"a": `package a; import (_ "b"; _ "e")`,
+		"b": `package b; import _ "c"`,
+		"c": `package c; func f() { _ = int(false) }`, // type error within function body
+		"d": `package d;`,
+		"e": `package e; import _ "d"`,
+	}
+	conf := loader.Config{
+		AllowErrors: true,
+		Build:       fakeContext(pkgs),
+	}
+	conf.Import("a")
+
+	prog, err := conf.Load()
+	if err != nil {
+		t.Errorf("Load failed: %s", err)
+	}
+	if prog == nil {
+		t.Fatalf("Load returned nil *Program")
+	}
+
+	for pkg, info := range prog.AllPackages {
+		var wantErr, wantTEF bool
+		switch pkg.Path() {
+		case "a", "b":
+		case "c":
+			wantErr = true
+		case "d", "e":
+			wantTEF = true
+		default:
+			t.Errorf("unexpected package: %q", pkg.Path())
+			continue
+		}
+
+		if (info.Errors != nil) != wantErr {
+			if wantErr {
+				t.Errorf("Package %q.Error = nil, want error", pkg.Path())
+			} else {
+				t.Errorf("Package %q has unexpected Errors: %v",
+					pkg.Path(), info.Errors)
+			}
+		}
+
+		if info.TransitivelyErrorFree != wantTEF {
+			t.Errorf("Package %q.TransitivelyErrorFree=%t, want %t",
+				pkg.Path(), info.TransitivelyErrorFree, wantTEF)
+		}
+	}
+}
+
+// Test that syntax (scan/parse), type, and loader errors are recorded
+// (in PackageInfo.Errors) and reported (via Config.TypeChecker.Error).
+func TestErrorReporting(t *testing.T) {
+	pkgs := map[string]string{
+		"a": `package a; import (_ "b"; _ "c"); var x int = false`,
+		"b": `package b; 'syntax error!`,
+	}
+	conf := loader.Config{
+		AllowErrors: true,
+		Build:       fakeContext(pkgs),
+	}
+	var mu sync.Mutex
+	var allErrors []error
+	conf.TypeChecker.Error = func(err error) {
+		mu.Lock()
+		allErrors = append(allErrors, err)
+		mu.Unlock()
+	}
+	conf.Import("a")
+
+	prog, err := conf.Load()
+	if err != nil {
+		t.Errorf("Load failed: %s", err)
+	}
+	if prog == nil {
+		t.Fatalf("Load returned nil *Program")
+	}
+
+	// TODO(adonovan): test keys of ImportMap.
+
+	// Check errors recorded in each PackageInfo.
+	for pkg, info := range prog.AllPackages {
+		switch pkg.Path() {
+		case "a":
+			if !hasError(info.Errors, "cannot convert false") {
+				t.Errorf("a.Errors = %v, want bool conversion (type) error", info.Errors)
+			}
+			if !hasError(info.Errors, "could not import c") {
+				t.Errorf("a.Errors = %v, want import (loader) error", info.Errors)
+			}
+		case "b":
+			if !hasError(info.Errors, "rune literal not terminated") {
+				t.Errorf("b.Errors = %v, want unterminated literal (syntax) error", info.Errors)
+			}
+		}
+	}
+
+	// Check errors reported via error handler.
+	if !hasError(allErrors, "cannot convert false") ||
+		!hasError(allErrors, "rune literal not terminated") ||
+		!hasError(allErrors, "could not import c") {
+		t.Errorf("allErrors = %v, want syntax, type and loader errors", allErrors)
+	}
+}
+
+func TestCycles(t *testing.T) {
+	for _, test := range []struct {
+		descr   string
+		ctxt    *build.Context
+		wantErr string
+	}{
+		{
+			"self-cycle",
+			fakeContext(map[string]string{
+				"main":      `package main; import _ "selfcycle"`,
+				"selfcycle": `package selfcycle; import _ "selfcycle"`,
+			}),
+			`import cycle: selfcycle -> selfcycle`,
+		},
+		{
+			"three-package cycle",
+			fakeContext(map[string]string{
+				"main": `package main; import _ "a"`,
+				"a":    `package a; import _ "b"`,
+				"b":    `package b; import _ "c"`,
+				"c":    `package c; import _ "a"`,
+			}),
+			`import cycle: c -> a -> b -> c`,
+		},
+		{
+			"self-cycle in dependency of test file",
+			buildutil.FakeContext(map[string]map[string]string{
+				"main": {
+					"main.go":      `package main`,
+					"main_test.go": `package main; import _ "a"`,
+				},
+				"a": {
+					"a.go": `package a; import _ "a"`,
+				},
+			}),
+			`import cycle: a -> a`,
+		},
+		// TODO(adonovan): fix: these fail
+		// {
+		// 	"two-package cycle in dependency of test file",
+		// 	buildutil.FakeContext(map[string]map[string]string{
+		// 		"main": {
+		// 			"main.go":      `package main`,
+		// 			"main_test.go": `package main; import _ "a"`,
+		// 		},
+		// 		"a": {
+		// 			"a.go": `package a; import _ "main"`,
+		// 		},
+		// 	}),
+		// 	`import cycle: main -> a -> main`,
+		// },
+		// {
+		// 	"self-cycle in augmented package",
+		// 	buildutil.FakeContext(map[string]map[string]string{
+		// 		"main": {
+		// 			"main.go":      `package main`,
+		// 			"main_test.go": `package main; import _ "main"`,
+		// 		},
+		// 	}),
+		// 	`import cycle: main -> main`,
+		// },
+	} {
+		conf := loader.Config{
+			AllowErrors: true,
+			Build:       test.ctxt,
+		}
+		var mu sync.Mutex
+		var allErrors []error
+		conf.TypeChecker.Error = func(err error) {
+			mu.Lock()
+			allErrors = append(allErrors, err)
+			mu.Unlock()
+		}
+		conf.ImportWithTests("main")
+
+		prog, err := conf.Load()
+		if err != nil {
+			t.Errorf("%s: Load failed: %s", test.descr, err)
+		}
+		if prog == nil {
+			t.Fatalf("%s: Load returned nil *Program", test.descr)
+		}
+
+		if !hasError(allErrors, test.wantErr) {
+			t.Errorf("%s: Load() errors = %q, want %q",
+				test.descr, allErrors, test.wantErr)
+		}
+	}
+
+	// TODO(adonovan):
+	// - Test that in a legal test cycle, none of the symbols
+	//   defined by augmentation are visible via import.
+}
+
+// ---- utilities ----
+
+// Simplifying wrapper around buildutil.FakeContext for single-file packages.
+func fakeContext(pkgs map[string]string) *build.Context {
+	pkgs2 := make(map[string]map[string]string)
+	for path, content := range pkgs {
+		pkgs2[path] = map[string]string{"x.go": content}
+	}
+	return buildutil.FakeContext(pkgs2)
+}
+
+func hasError(errors []error, substr string) bool {
+	for _, err := range errors {
+		if strings.Contains(err.Error(), substr) {
+			return true
+		}
+	}
+	return false
+}
+
+func keys(m map[string]bool) (keys []string) {
+	for key := range m {
+		keys = append(keys, key)
+	}
+	sort.Strings(keys)
+	return
+}
+
+// Returns all loaded packages.
+func all(prog *loader.Program) []string {
+	var pkgs []string
+	for _, info := range prog.AllPackages {
+		pkgs = append(pkgs, info.Pkg.Path())
+	}
+	sort.Strings(pkgs)
+	return pkgs
+}
+
+// Returns initially imported packages, as a string.
+func imported(prog *loader.Program) string {
+	var pkgs []string
+	for _, info := range prog.Imported {
+		pkgs = append(pkgs, info.Pkg.Path())
+	}
+	sort.Strings(pkgs)
+	return strings.Join(pkgs, " ")
+}
+
+// Returns initially created packages, as a string.
+func created(prog *loader.Program) string {
+	var pkgs []string
+	for _, info := range prog.Created {
+		pkgs = append(pkgs, info.Pkg.Path())
+	}
+	return strings.Join(pkgs, " ")
+}

Godeps/_workspace/src/golang.org/x/tools/go/loader/stdlib_test.go

@@ -0,0 +1,192 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package loader_test
+
+// This file enumerates all packages beneath $GOROOT, loads them, plus
+// their external tests if any, runs the type checker on them, and
+// prints some summary information.
+//
+// Run test with GOMAXPROCS=8.
+
+import (
+	"bytes"
+	"fmt"
+	"go/ast"
+	"go/build"
+	"go/token"
+	"io/ioutil"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+	"time"
+
+	"golang.org/x/tools/go/buildutil"
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/go/types"
+)
+
+func TestStdlib(t *testing.T) {
+	runtime.GC()
+	t0 := time.Now()
+	var memstats runtime.MemStats
+	runtime.ReadMemStats(&memstats)
+	alloc := memstats.Alloc
+
+	// Load, parse and type-check the program.
+	ctxt := build.Default // copy
+	ctxt.GOPATH = ""      // disable GOPATH
+	conf := loader.Config{Build: &ctxt}
+	for _, path := range buildutil.AllPackages(conf.Build) {
+		conf.ImportWithTests(path)
+	}
+
+	prog, err := conf.Load()
+	if err != nil {
+		t.Fatalf("Load failed: %v", err)
+	}
+
+	t1 := time.Now()
+	runtime.GC()
+	runtime.ReadMemStats(&memstats)
+
+	numPkgs := len(prog.AllPackages)
+	if want := 205; numPkgs < want {
+		t.Errorf("Loaded only %d packages, want at least %d", numPkgs, want)
+	}
+
+	// Dump package members.
+	if false {
+		for pkg := range prog.AllPackages {
+			fmt.Printf("Package %s:\n", pkg.Path())
+			scope := pkg.Scope()
+			qualifier := types.RelativeTo(pkg)
+			for _, name := range scope.Names() {
+				if ast.IsExported(name) {
+					fmt.Printf("\t%s\n", types.ObjectString(scope.Lookup(name), qualifier))
+				}
+			}
+			fmt.Println()
+		}
+	}
+
+	// Check that Test functions for io/ioutil, regexp and
+	// compress/bzip2 are all simultaneously present.
+	// (The apparent cycle formed when augmenting all three of
+	// these packages by their tests was the original motivation
+	// for reporting b/7114.)
+	//
+	// compress/bzip2.TestBitReader in bzip2_test.go    imports io/ioutil
+	// io/ioutil.TestTempFile       in tempfile_test.go imports regexp
+	// regexp.TestRE2Search         in exec_test.go     imports compress/bzip2
+	for _, test := range []struct{ pkg, fn string }{
+		{"io/ioutil", "TestTempFile"},
+		{"regexp", "TestRE2Search"},
+		{"compress/bzip2", "TestBitReader"},
+	} {
+		info := prog.Imported[test.pkg]
+		if info == nil {
+			t.Errorf("failed to load package %q", test.pkg)
+			continue
+		}
+		obj, _ := info.Pkg.Scope().Lookup(test.fn).(*types.Func)
+		if obj == nil {
+			t.Errorf("package %q has no func %q", test.pkg, test.fn)
+			continue
+		}
+	}
+
+	// Dump some statistics.
+
+	// determine line count
+	var lineCount int
+	prog.Fset.Iterate(func(f *token.File) bool {
+		lineCount += f.LineCount()
+		return true
+	})
+
+	t.Log("GOMAXPROCS:           ", runtime.GOMAXPROCS(0))
+	t.Log("#Source lines:        ", lineCount)
+	t.Log("Load/parse/typecheck: ", t1.Sub(t0))
+	t.Log("#MB:                  ", int64(memstats.Alloc-alloc)/1000000)
+}
+
+func TestCgoOption(t *testing.T) {
+	switch runtime.GOOS {
+	// On these systems, the net and os/user packages don't use cgo.
+	case "plan9", "solaris", "windows":
+		return
+	}
+	// In nocgo builds (e.g. linux-amd64-nocgo),
+	// there is no "runtime/cgo" package,
+	// so cgo-generated Go files will have a failing import.
+	if !build.Default.CgoEnabled {
+		return
+	}
+	// Test that we can load cgo-using packages with
+	// CGO_ENABLED=[01], which causes go/build to select pure
+	// Go/native implementations, respectively, based on build
+	// tags.
+	//
+	// Each entry specifies a package-level object and the generic
+	// file expected to define it when cgo is disabled.
+	// When cgo is enabled, the exact file is not specified (since
+	// it varies by platform), but must differ from the generic one.
+	//
+	// The test also loads the actual file to verify that the
+	// object is indeed defined at that location.
+	for _, test := range []struct {
+		pkg, name, genericFile string
+	}{
+		{"net", "cgoLookupHost", "cgo_stub.go"},
+		{"os/user", "lookupId", "lookup_stubs.go"},
+	} {
+		ctxt := build.Default
+		for _, ctxt.CgoEnabled = range []bool{false, true} {
+			conf := loader.Config{Build: &ctxt}
+			conf.Import(test.pkg)
+			prog, err := conf.Load()
+			if err != nil {
+				t.Errorf("Load failed: %v", err)
+				continue
+			}
+			info := prog.Imported[test.pkg]
+			if info == nil {
+				t.Errorf("package %s not found", test.pkg)
+				continue
+			}
+			obj := info.Pkg.Scope().Lookup(test.name)
+			if obj == nil {
+				t.Errorf("no object %s.%s", test.pkg, test.name)
+				continue
+			}
+			posn := prog.Fset.Position(obj.Pos())
+			t.Logf("%s: %s (CgoEnabled=%t)", posn, obj, ctxt.CgoEnabled)
+
+			gotFile := filepath.Base(posn.Filename)
+			filesMatch := gotFile == test.genericFile
+
+			if ctxt.CgoEnabled && filesMatch {
+				t.Errorf("CGO_ENABLED=1: %s found in %s, want native file",
+					obj, gotFile)
+			} else if !ctxt.CgoEnabled && !filesMatch {
+				t.Errorf("CGO_ENABLED=0: %s found in %s, want %s",
+					obj, gotFile, test.genericFile)
+			}
+
+			// Load the file and check the object is declared at the right place.
+			b, err := ioutil.ReadFile(posn.Filename)
+			if err != nil {
+				t.Errorf("can't read %s: %s", posn.Filename, err)
+				continue
+			}
+			line := string(bytes.Split(b, []byte("\n"))[posn.Line-1])
+			ident := line[posn.Column-1:]
+			if !strings.HasPrefix(ident, test.name) {
+				t.Errorf("%s: %s not declared here (looking at %q)", posn, obj, ident)
+			}
+		}
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/loader/util.go

@@ -0,0 +1,124 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package loader
+
+import (
+	"go/ast"
+	"go/build"
+	"go/parser"
+	"go/token"
+	"io"
+	"os"
+	"strconv"
+	"sync"
+
+	"golang.org/x/tools/go/buildutil"
+)
+
+// We use a counting semaphore to limit
+// the number of parallel I/O calls per process.
+var sema = make(chan bool, 10)
+
+// parseFiles parses the Go source files within directory dir and
+// returns the ASTs of the ones that could be at least partially parsed,
+// along with a list of I/O and parse errors encountered.
+//
+// I/O is done via ctxt, which may specify a virtual file system.
+// displayPath is used to transform the filenames attached to the ASTs.
+//
+func parseFiles(fset *token.FileSet, ctxt *build.Context, displayPath func(string) string, dir string, files []string, mode parser.Mode) ([]*ast.File, []error) {
+	if displayPath == nil {
+		displayPath = func(path string) string { return path }
+	}
+	var wg sync.WaitGroup
+	n := len(files)
+	parsed := make([]*ast.File, n)
+	errors := make([]error, n)
+	for i, file := range files {
+		if !buildutil.IsAbsPath(ctxt, file) {
+			file = buildutil.JoinPath(ctxt, dir, file)
+		}
+		wg.Add(1)
+		go func(i int, file string) {
+			sema <- true // wait
+			defer func() {
+				wg.Done()
+				<-sema // signal
+			}()
+			var rd io.ReadCloser
+			var err error
+			if ctxt.OpenFile != nil {
+				rd, err = ctxt.OpenFile(file)
+			} else {
+				rd, err = os.Open(file)
+			}
+			if err != nil {
+				errors[i] = err // open failed
+				return
+			}
+
+			// ParseFile may return both an AST and an error.
+			parsed[i], errors[i] = parser.ParseFile(fset, displayPath(file), rd, mode)
+			rd.Close()
+		}(i, file)
+	}
+	wg.Wait()
+
+	// Eliminate nils, preserving order.
+	var o int
+	for _, f := range parsed {
+		if f != nil {
+			parsed[o] = f
+			o++
+		}
+	}
+	parsed = parsed[:o]
+
+	o = 0
+	for _, err := range errors {
+		if err != nil {
+			errors[o] = err
+			o++
+		}
+	}
+	errors = errors[:o]
+
+	return parsed, errors
+}
+
+// scanImports returns the set of all package import paths from all
+// import specs in the specified files.
+func scanImports(files []*ast.File) map[string]bool {
+	imports := make(map[string]bool)
+	for _, f := range files {
+		for _, decl := range f.Decls {
+			if decl, ok := decl.(*ast.GenDecl); ok && decl.Tok == token.IMPORT {
+				for _, spec := range decl.Specs {
+					spec := spec.(*ast.ImportSpec)
+
+					// NB: do not assume the program is well-formed!
+					path, err := strconv.Unquote(spec.Path.Value)
+					if err != nil {
+						continue // quietly ignore the error
+					}
+					if path == "C" || path == "unsafe" {
+						continue // skip pseudo packages
+					}
+					imports[path] = true
+				}
+			}
+		}
+	}
+	return imports
+}
+
+// ---------- Internal helpers ----------
+
+// TODO(adonovan): make this a method: func (*token.File) Contains(token.Pos)
+func tokenFileContainsPos(f *token.File, pos token.Pos) bool {
+	p := int(pos)
+	base := f.Base()
+	return base <= p && p < base+f.Size()
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/api.go

@@ -0,0 +1,365 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package types declares the data types and implements
+// the algorithms for type-checking of Go packages.
+// Use Check and Config.Check to invoke the type-checker.
+//
+// Type-checking consists of several interdependent phases:
+//
+// Name resolution maps each identifier (ast.Ident) in the program to the
+// language object (Object) it denotes.
+// Use Info.{Defs,Uses,Implicits} for the results of name resolution.
+//
+// Constant folding computes the exact constant value (exact.Value) for
+// every expression (ast.Expr) that is a compile-time constant.
+// Use Info.Types[expr].Value for the results of constant folding.
+//
+// Type inference computes the type (Type) of every expression (ast.Expr)
+// and checks for compliance with the language specification.
+// Use Info.Types[expr].Type for the results of type inference.
+//
+package types
+
+import (
+	"bytes"
+	"fmt"
+	"go/ast"
+	"go/token"
+
+	"golang.org/x/tools/go/exact"
+)
+
+// Check type-checks a package and returns the resulting complete package
+// object, or a nil package and the first error. The package is specified
+// by a list of *ast.Files and corresponding file set, and the import path
+// the package is identified with. The clean path must not be empty or dot (".").
+//
+// For more control over type-checking and results, use Config.Check.
+func Check(path string, fset *token.FileSet, files []*ast.File) (*Package, error) {
+	var conf Config
+	pkg, err := conf.Check(path, fset, files, nil)
+	if err != nil {
+		return nil, err
+	}
+	return pkg, nil
+}
+
+// An Error describes a type-checking error; it implements the error interface.
+// A "soft" error is an error that still permits a valid interpretation of a
+// package (such as "unused variable"); "hard" errors may lead to unpredictable
+// behavior if ignored.
+type Error struct {
+	Fset *token.FileSet // file set for interpretation of Pos
+	Pos  token.Pos      // error position
+	Msg  string         // error message
+	Soft bool           // if set, error is "soft"
+}
+
+// Error returns an error string formatted as follows:
+// filename:line:column: message
+func (err Error) Error() string {
+	return fmt.Sprintf("%s: %s", err.Fset.Position(err.Pos), err.Msg)
+}
+
+// An importer resolves import paths to Packages.
+// The imports map records packages already known,
+// indexed by package path. The type-checker
+// will invoke Import with Config.Packages.
+// An importer must determine the canonical package path and
+// check imports to see if it is already present in the map.
+// If so, the Importer can return the map entry.  Otherwise,
+// the importer must load the package data for the given path
+// into a new *Package, record it in imports map, and return
+// the package.
+// TODO(gri) Need to be clearer about requirements of completeness.
+type Importer func(map[string]*Package, string) (*Package, error)
+
+// A Config specifies the configuration for type checking.
+// The zero value for Config is a ready-to-use default configuration.
+type Config struct {
+	// If IgnoreFuncBodies is set, function bodies are not
+	// type-checked.
+	IgnoreFuncBodies bool
+
+	// If FakeImportC is set, `import "C"` (for packages requiring Cgo)
+	// declares an empty "C" package and errors are omitted for qualified
+	// identifiers referring to package C (which won't find an object).
+	// This feature is intended for the standard library cmd/api tool.
+	//
+	// Caution: Effects may be unpredictable due to follow-up errors.
+	//          Do not use casually!
+	FakeImportC bool
+
+	// Packages is used to look up (and thus canonicalize) packages by
+	// package path. If Packages is nil, it is set to a new empty map.
+	// During type-checking, imported packages are added to the map.
+	Packages map[string]*Package
+
+	// If Error != nil, it is called with each error found
+	// during type checking; err has dynamic type Error.
+	// Secondary errors (for instance, to enumerate all types
+	// involved in an invalid recursive type declaration) have
+	// error strings that start with a '\t' character.
+	// If Error == nil, type-checking stops with the first
+	// error found.
+	Error func(err error)
+
+	// If Import != nil, it is called for each imported package.
+	// Otherwise, DefaultImport is called.
+	Import Importer
+
+	// If Sizes != nil, it provides the sizing functions for package unsafe.
+	// Otherwise &StdSizes{WordSize: 8, MaxAlign: 8} is used instead.
+	Sizes Sizes
+
+	// If DisableUnusedImportCheck is set, packages are not checked
+	// for unused imports.
+	DisableUnusedImportCheck bool
+}
+
+// DefaultImport is the default importer invoked if Config.Import == nil.
+// The declaration:
+//
+//	import _ "golang.org/x/tools/go/gcimporter"
+//
+// in a client of go/types will initialize DefaultImport to gcimporter.Import.
+var DefaultImport Importer
+
+// Info holds result type information for a type-checked package.
+// Only the information for which a map is provided is collected.
+// If the package has type errors, the collected information may
+// be incomplete.
+type Info struct {
+	// Types maps expressions to their types, and for constant
+	// expressions, their values. Invalid expressions are omitted.
+	//
+	// For (possibly parenthesized) identifiers denoting built-in
+	// functions, the recorded signatures are call-site specific:
+	// if the call result is not a constant, the recorded type is
+	// an argument-specific signature. Otherwise, the recorded type
+	// is invalid.
+	//
+	// Identifiers on the lhs of declarations (i.e., the identifiers
+	// which are being declared) are collected in the Defs map.
+	// Identifiers denoting packages are collected in the Uses maps.
+	Types map[ast.Expr]TypeAndValue
+
+	// Defs maps identifiers to the objects they define (including
+	// package names, dots "." of dot-imports, and blank "_" identifiers).
+	// For identifiers that do not denote objects (e.g., the package name
+	// in package clauses, or symbolic variables t in t := x.(type) of
+	// type switch headers), the corresponding objects are nil.
+	//
+	// For an anonymous field, Defs returns the field *Var it defines.
+	//
+	// Invariant: Defs[id] == nil || Defs[id].Pos() == id.Pos()
+	Defs map[*ast.Ident]Object
+
+	// Uses maps identifiers to the objects they denote.
+	//
+	// For an anonymous field, Uses returns the *TypeName it denotes.
+	//
+	// Invariant: Uses[id].Pos() != id.Pos()
+	Uses map[*ast.Ident]Object
+
+	// Implicits maps nodes to their implicitly declared objects, if any.
+	// The following node and object types may appear:
+	//
+	//	node               declared object
+	//
+	//	*ast.ImportSpec    *PkgName for dot-imports and imports without renames
+	//	*ast.CaseClause    type-specific *Var for each type switch case clause (incl. default)
+	//      *ast.Field         anonymous struct field or parameter *Var
+	//
+	Implicits map[ast.Node]Object
+
+	// Selections maps selector expressions (excluding qualified identifiers)
+	// to their corresponding selections.
+	Selections map[*ast.SelectorExpr]*Selection
+
+	// Scopes maps ast.Nodes to the scopes they define. Package scopes are not
+	// associated with a specific node but with all files belonging to a package.
+	// Thus, the package scope can be found in the type-checked Package object.
+	// Scopes nest, with the Universe scope being the outermost scope, enclosing
+	// the package scope, which contains (one or more) files scopes, which enclose
+	// function scopes which in turn enclose statement and function literal scopes.
+	// Note that even though package-level functions are declared in the package
+	// scope, the function scopes are embedded in the file scope of the file
+	// containing the function declaration.
+	//
+	// The following node types may appear in Scopes:
+	//
+	//	*ast.File
+	//	*ast.FuncType
+	//	*ast.BlockStmt
+	//	*ast.IfStmt
+	//	*ast.SwitchStmt
+	//	*ast.TypeSwitchStmt
+	//	*ast.CaseClause
+	//	*ast.CommClause
+	//	*ast.ForStmt
+	//	*ast.RangeStmt
+	//
+	Scopes map[ast.Node]*Scope
+
+	// InitOrder is the list of package-level initializers in the order in which
+	// they must be executed. Initializers referring to variables related by an
+	// initialization dependency appear in topological order, the others appear
+	// in source order. Variables without an initialization expression do not
+	// appear in this list.
+	InitOrder []*Initializer
+}
+
+// TypeOf returns the type of expression e, or nil if not found.
+// Precondition: the Types, Uses and Defs maps are populated.
+//
+func (info *Info) TypeOf(e ast.Expr) Type {
+	if t, ok := info.Types[e]; ok {
+		return t.Type
+	}
+	if id, _ := e.(*ast.Ident); id != nil {
+		if obj := info.ObjectOf(id); obj != nil {
+			return obj.Type()
+		}
+	}
+	return nil
+}
+
+// ObjectOf returns the object denoted by the specified id,
+// or nil if not found.
+//
+// If id is an anonymous struct field, ObjectOf returns the field (*Var)
+// it uses, not the type (*TypeName) it defines.
+//
+// Precondition: the Uses and Defs maps are populated.
+//
+func (info *Info) ObjectOf(id *ast.Ident) Object {
+	if obj, _ := info.Defs[id]; obj != nil {
+		return obj
+	}
+	return info.Uses[id]
+}
+
+// TypeAndValue reports the type and value (for constants)
+// of the corresponding expression.
+type TypeAndValue struct {
+	mode  operandMode
+	Type  Type
+	Value exact.Value
+}
+
+// TODO(gri) Consider eliminating the IsVoid predicate. Instead, report
+// "void" values as regular values but with the empty tuple type.
+
+// IsVoid reports whether the corresponding expression
+// is a function call without results.
+func (tv TypeAndValue) IsVoid() bool {
+	return tv.mode == novalue
+}
+
+// IsType reports whether the corresponding expression specifies a type.
+func (tv TypeAndValue) IsType() bool {
+	return tv.mode == typexpr
+}
+
+// IsBuiltin reports whether the corresponding expression denotes
+// a (possibly parenthesized) built-in function.
+func (tv TypeAndValue) IsBuiltin() bool {
+	return tv.mode == builtin
+}
+
+// IsValue reports whether the corresponding expression is a value.
+// Builtins are not considered values. Constant values have a non-
+// nil Value.
+func (tv TypeAndValue) IsValue() bool {
+	switch tv.mode {
+	case constant, variable, mapindex, value, commaok:
+		return true
+	}
+	return false
+}
+
+// IsNil reports whether the corresponding expression denotes the
+// predeclared value nil.
+func (tv TypeAndValue) IsNil() bool {
+	return tv.mode == value && tv.Type == Typ[UntypedNil]
+}
+
+// Addressable reports whether the corresponding expression
+// is addressable (http://golang.org/ref/spec#Address_operators).
+func (tv TypeAndValue) Addressable() bool {
+	return tv.mode == variable
+}
+
+// Assignable reports whether the corresponding expression
+// is assignable to (provided a value of the right type).
+func (tv TypeAndValue) Assignable() bool {
+	return tv.mode == variable || tv.mode == mapindex
+}
+
+// HasOk reports whether the corresponding expression may be
+// used on the lhs of a comma-ok assignment.
+func (tv TypeAndValue) HasOk() bool {
+	return tv.mode == commaok || tv.mode == mapindex
+}
+
+// An Initializer describes a package-level variable, or a list of variables in case
+// of a multi-valued initialization expression, and the corresponding initialization
+// expression.
+type Initializer struct {
+	Lhs []*Var // var Lhs = Rhs
+	Rhs ast.Expr
+}
+
+func (init *Initializer) String() string {
+	var buf bytes.Buffer
+	for i, lhs := range init.Lhs {
+		if i > 0 {
+			buf.WriteString(", ")
+		}
+		buf.WriteString(lhs.Name())
+	}
+	buf.WriteString(" = ")
+	WriteExpr(&buf, init.Rhs)
+	return buf.String()
+}
+
+// Check type-checks a package and returns the resulting package object,
+// the first error if any, and if info != nil, additional type information.
+// The package is marked as complete if no errors occurred, otherwise it is
+// incomplete. See Config.Error for controlling behavior in the presence of
+// errors.
+//
+// The package is specified by a list of *ast.Files and corresponding
+// file set, and the package path the package is identified with.
+// The clean path must not be empty or dot (".").
+func (conf *Config) Check(path string, fset *token.FileSet, files []*ast.File, info *Info) (*Package, error) {
+	pkg := NewPackage(path, "")
+	return pkg, NewChecker(conf, fset, pkg, info).Files(files)
+}
+
+// AssertableTo reports whether a value of type V can be asserted to have type T.
+func AssertableTo(V *Interface, T Type) bool {
+	m, _ := assertableTo(V, T)
+	return m == nil
+}
+
+// AssignableTo reports whether a value of type V is assignable to a variable of type T.
+func AssignableTo(V, T Type) bool {
+	x := operand{mode: value, typ: V}
+	return x.assignableTo(nil, T) // config not needed for non-constant x
+}
+
+// ConvertibleTo reports whether a value of type V is convertible to a value of type T.
+func ConvertibleTo(V, T Type) bool {
+	x := operand{mode: value, typ: V}
+	return x.convertibleTo(nil, T) // config not needed for non-constant x
+}
+
+// Implements reports whether type V implements interface T.
+func Implements(V Type, T *Interface) bool {
+	f, _ := MissingMethod(V, T, true)
+	return f == nil
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/assignments.go

@@ -0,0 +1,328 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements initialization and assignment checks.
+
+package types
+
+import (
+	"go/ast"
+	"go/token"
+)
+
+// assignment reports whether x can be assigned to a variable of type T,
+// if necessary by attempting to convert untyped values to the appropriate
+// type. If x.mode == invalid upon return, then assignment has already
+// issued an error message and the caller doesn't have to report another.
+// Use T == nil to indicate assignment to an untyped blank identifier.
+//
+// TODO(gri) Should find a better way to handle in-band errors.
+//
+func (check *Checker) assignment(x *operand, T Type) bool {
+	switch x.mode {
+	case invalid:
+		return true // error reported before
+	case constant, variable, mapindex, value, commaok:
+		// ok
+	default:
+		unreachable()
+	}
+
+	// x must be a single value
+	// (tuple types are never named - no need for underlying type)
+	if t, _ := x.typ.(*Tuple); t != nil {
+		assert(t.Len() > 1)
+		check.errorf(x.pos(), "%d-valued expression %s used as single value", t.Len(), x)
+		x.mode = invalid
+		return false
+	}
+
+	if isUntyped(x.typ) {
+		target := T
+		// spec: "If an untyped constant is assigned to a variable of interface
+		// type or the blank identifier, the constant is first converted to type
+		// bool, rune, int, float64, complex128 or string respectively, depending
+		// on whether the value is a boolean, rune, integer, floating-point, complex,
+		// or string constant."
+		if T == nil || IsInterface(T) {
+			if T == nil && x.typ == Typ[UntypedNil] {
+				check.errorf(x.pos(), "use of untyped nil")
+				x.mode = invalid
+				return false
+			}
+			target = defaultType(x.typ)
+		}
+		check.convertUntyped(x, target)
+		if x.mode == invalid {
+			return false
+		}
+	}
+
+	// spec: "If a left-hand side is the blank identifier, any typed or
+	// non-constant value except for the predeclared identifier nil may
+	// be assigned to it."
+	return T == nil || x.assignableTo(check.conf, T)
+}
+
+func (check *Checker) initConst(lhs *Const, x *operand) {
+	if x.mode == invalid || x.typ == Typ[Invalid] || lhs.typ == Typ[Invalid] {
+		if lhs.typ == nil {
+			lhs.typ = Typ[Invalid]
+		}
+		return
+	}
+
+	// rhs must be a constant
+	if x.mode != constant {
+		check.errorf(x.pos(), "%s is not constant", x)
+		if lhs.typ == nil {
+			lhs.typ = Typ[Invalid]
+		}
+		return
+	}
+	assert(isConstType(x.typ))
+
+	// If the lhs doesn't have a type yet, use the type of x.
+	if lhs.typ == nil {
+		lhs.typ = x.typ
+	}
+
+	if !check.assignment(x, lhs.typ) {
+		if x.mode != invalid {
+			check.errorf(x.pos(), "cannot define constant %s (type %s) as %s", lhs.Name(), lhs.typ, x)
+		}
+		return
+	}
+
+	lhs.val = x.val
+}
+
+// If result is set, lhs is a function result parameter and x is a return result.
+func (check *Checker) initVar(lhs *Var, x *operand, result bool) Type {
+	if x.mode == invalid || x.typ == Typ[Invalid] || lhs.typ == Typ[Invalid] {
+		if lhs.typ == nil {
+			lhs.typ = Typ[Invalid]
+		}
+		return nil
+	}
+
+	// If the lhs doesn't have a type yet, use the type of x.
+	if lhs.typ == nil {
+		typ := x.typ
+		if isUntyped(typ) {
+			// convert untyped types to default types
+			if typ == Typ[UntypedNil] {
+				check.errorf(x.pos(), "use of untyped nil")
+				lhs.typ = Typ[Invalid]
+				return nil
+			}
+			typ = defaultType(typ)
+		}
+		lhs.typ = typ
+	}
+
+	if !check.assignment(x, lhs.typ) {
+		if x.mode != invalid {
+			if result {
+				// don't refer to lhs.name because it may be an anonymous result parameter
+				check.errorf(x.pos(), "cannot return %s as value of type %s", x, lhs.typ)
+			} else {
+				check.errorf(x.pos(), "cannot initialize %s with %s", lhs, x)
+			}
+		}
+		return nil
+	}
+
+	return x.typ
+}
+
+func (check *Checker) assignVar(lhs ast.Expr, x *operand) Type {
+	if x.mode == invalid || x.typ == Typ[Invalid] {
+		return nil
+	}
+
+	// Determine if the lhs is a (possibly parenthesized) identifier.
+	ident, _ := unparen(lhs).(*ast.Ident)
+
+	// Don't evaluate lhs if it is the blank identifier.
+	if ident != nil && ident.Name == "_" {
+		check.recordDef(ident, nil)
+		if !check.assignment(x, nil) {
+			assert(x.mode == invalid)
+			x.typ = nil
+		}
+		return x.typ
+	}
+
+	// If the lhs is an identifier denoting a variable v, this assignment
+	// is not a 'use' of v. Remember current value of v.used and restore
+	// after evaluating the lhs via check.expr.
+	var v *Var
+	var v_used bool
+	if ident != nil {
+		if _, obj := check.scope.LookupParent(ident.Name, token.NoPos); obj != nil {
+			v, _ = obj.(*Var)
+			if v != nil {
+				v_used = v.used
+			}
+		}
+	}
+
+	var z operand
+	check.expr(&z, lhs)
+	if v != nil {
+		v.used = v_used // restore v.used
+	}
+
+	if z.mode == invalid || z.typ == Typ[Invalid] {
+		return nil
+	}
+
+	// spec: "Each left-hand side operand must be addressable, a map index
+	// expression, or the blank identifier. Operands may be parenthesized."
+	switch z.mode {
+	case invalid:
+		return nil
+	case variable, mapindex:
+		// ok
+	default:
+		check.errorf(z.pos(), "cannot assign to %s", &z)
+		return nil
+	}
+
+	if !check.assignment(x, z.typ) {
+		if x.mode != invalid {
+			check.errorf(x.pos(), "cannot assign %s to %s", x, &z)
+		}
+		return nil
+	}
+
+	return x.typ
+}
+
+// If returnPos is valid, initVars is called to type-check the assignment of
+// return expressions, and returnPos is the position of the return statement.
+func (check *Checker) initVars(lhs []*Var, rhs []ast.Expr, returnPos token.Pos) {
+	l := len(lhs)
+	get, r, commaOk := unpack(func(x *operand, i int) { check.expr(x, rhs[i]) }, len(rhs), l == 2 && !returnPos.IsValid())
+	if get == nil || l != r {
+		// invalidate lhs and use rhs
+		for _, obj := range lhs {
+			if obj.typ == nil {
+				obj.typ = Typ[Invalid]
+			}
+		}
+		if get == nil {
+			return // error reported by unpack
+		}
+		check.useGetter(get, r)
+		if returnPos.IsValid() {
+			check.errorf(returnPos, "wrong number of return values (want %d, got %d)", l, r)
+			return
+		}
+		check.errorf(rhs[0].Pos(), "assignment count mismatch (%d vs %d)", l, r)
+		return
+	}
+
+	var x operand
+	if commaOk {
+		var a [2]Type
+		for i := range a {
+			get(&x, i)
+			a[i] = check.initVar(lhs[i], &x, returnPos.IsValid())
+		}
+		check.recordCommaOkTypes(rhs[0], a)
+		return
+	}
+
+	for i, lhs := range lhs {
+		get(&x, i)
+		check.initVar(lhs, &x, returnPos.IsValid())
+	}
+}
+
+func (check *Checker) assignVars(lhs, rhs []ast.Expr) {
+	l := len(lhs)
+	get, r, commaOk := unpack(func(x *operand, i int) { check.expr(x, rhs[i]) }, len(rhs), l == 2)
+	if get == nil {
+		return // error reported by unpack
+	}
+	if l != r {
+		check.useGetter(get, r)
+		check.errorf(rhs[0].Pos(), "assignment count mismatch (%d vs %d)", l, r)
+		return
+	}
+
+	var x operand
+	if commaOk {
+		var a [2]Type
+		for i := range a {
+			get(&x, i)
+			a[i] = check.assignVar(lhs[i], &x)
+		}
+		check.recordCommaOkTypes(rhs[0], a)
+		return
+	}
+
+	for i, lhs := range lhs {
+		get(&x, i)
+		check.assignVar(lhs, &x)
+	}
+}
+
+func (check *Checker) shortVarDecl(pos token.Pos, lhs, rhs []ast.Expr) {
+	scope := check.scope
+
+	// collect lhs variables
+	var newVars []*Var
+	var lhsVars = make([]*Var, len(lhs))
+	for i, lhs := range lhs {
+		var obj *Var
+		if ident, _ := lhs.(*ast.Ident); ident != nil {
+			// Use the correct obj if the ident is redeclared. The
+			// variable's scope starts after the declaration; so we
+			// must use Scope.Lookup here and call Scope.Insert
+			// (via check.declare) later.
+			name := ident.Name
+			if alt := scope.Lookup(name); alt != nil {
+				// redeclared object must be a variable
+				if alt, _ := alt.(*Var); alt != nil {
+					obj = alt
+				} else {
+					check.errorf(lhs.Pos(), "cannot assign to %s", lhs)
+				}
+				check.recordUse(ident, alt)
+			} else {
+				// declare new variable, possibly a blank (_) variable
+				obj = NewVar(ident.Pos(), check.pkg, name, nil)
+				if name != "_" {
+					newVars = append(newVars, obj)
+				}
+				check.recordDef(ident, obj)
+			}
+		} else {
+			check.errorf(lhs.Pos(), "cannot declare %s", lhs)
+		}
+		if obj == nil {
+			obj = NewVar(lhs.Pos(), check.pkg, "_", nil) // dummy variable
+		}
+		lhsVars[i] = obj
+	}
+
+	check.initVars(lhsVars, rhs, token.NoPos)
+
+	// declare new variables
+	if len(newVars) > 0 {
+		// spec: "The scope of a constant or variable identifier declared inside
+		// a function begins at the end of the ConstSpec or VarSpec (ShortVarDecl
+		// for short variable declarations) and ends at the end of the innermost
+		// containing block."
+		scopePos := rhs[len(rhs)-1].End()
+		for _, obj := range newVars {
+			check.declare(scope, nil, obj, scopePos) // recordObject already called
+		}
+	} else {
+		check.softErrorf(pos, "no new variables on left side of :=")
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/builtins.go

@@ -0,0 +1,628 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements typechecking of builtin function calls.
+
+package types
+
+import (
+	"go/ast"
+	"go/token"
+
+	"golang.org/x/tools/go/exact"
+)
+
+// builtin type-checks a call to the built-in specified by id and
+// returns true if the call is valid, with *x holding the result;
+// but x.expr is not set. If the call is invalid, the result is
+// false, and *x is undefined.
+//
+func (check *Checker) builtin(x *operand, call *ast.CallExpr, id builtinId) (_ bool) {
+	// append is the only built-in that permits the use of ... for the last argument
+	bin := predeclaredFuncs[id]
+	if call.Ellipsis.IsValid() && id != _Append {
+		check.invalidOp(call.Ellipsis, "invalid use of ... with built-in %s", bin.name)
+		check.use(call.Args...)
+		return
+	}
+
+	// For len(x) and cap(x) we need to know if x contains any function calls or
+	// receive operations. Save/restore current setting and set hasCallOrRecv to
+	// false for the evaluation of x so that we can check it afterwards.
+	// Note: We must do this _before_ calling unpack because unpack evaluates the
+	//       first argument before we even call arg(x, 0)!
+	if id == _Len || id == _Cap {
+		defer func(b bool) {
+			check.hasCallOrRecv = b
+		}(check.hasCallOrRecv)
+		check.hasCallOrRecv = false
+	}
+
+	// determine actual arguments
+	var arg getter
+	nargs := len(call.Args)
+	switch id {
+	default:
+		// make argument getter
+		arg, nargs, _ = unpack(func(x *operand, i int) { check.expr(x, call.Args[i]) }, nargs, false)
+		if arg == nil {
+			return
+		}
+		// evaluate first argument, if present
+		if nargs > 0 {
+			arg(x, 0)
+			if x.mode == invalid {
+				return
+			}
+		}
+	case _Make, _New, _Offsetof, _Trace:
+		// arguments require special handling
+	}
+
+	// check argument count
+	{
+		msg := ""
+		if nargs < bin.nargs {
+			msg = "not enough"
+		} else if !bin.variadic && nargs > bin.nargs {
+			msg = "too many"
+		}
+		if msg != "" {
+			check.invalidOp(call.Rparen, "%s arguments for %s (expected %d, found %d)", msg, call, bin.nargs, nargs)
+			return
+		}
+	}
+
+	switch id {
+	case _Append:
+		// append(s S, x ...T) S, where T is the element type of S
+		// spec: "The variadic function append appends zero or more values x to s of type
+		// S, which must be a slice type, and returns the resulting slice, also of type S.
+		// The values x are passed to a parameter of type ...T where T is the element type
+		// of S and the respective parameter passing rules apply."
+		S := x.typ
+		var T Type
+		if s, _ := S.Underlying().(*Slice); s != nil {
+			T = s.elem
+		} else {
+			check.invalidArg(x.pos(), "%s is not a slice", x)
+			return
+		}
+
+		// remember arguments that have been evaluated already
+		alist := []operand{*x}
+
+		// spec: "As a special case, append also accepts a first argument assignable
+		// to type []byte with a second argument of string type followed by ... .
+		// This form appends the bytes of the string.
+		if nargs == 2 && call.Ellipsis.IsValid() && x.assignableTo(check.conf, NewSlice(universeByte)) {
+			arg(x, 1)
+			if x.mode == invalid {
+				return
+			}
+			if isString(x.typ) {
+				if check.Types != nil {
+					sig := makeSig(S, S, x.typ)
+					sig.variadic = true
+					check.recordBuiltinType(call.Fun, sig)
+				}
+				x.mode = value
+				x.typ = S
+				break
+			}
+			alist = append(alist, *x)
+			// fallthrough
+		}
+
+		// check general case by creating custom signature
+		sig := makeSig(S, S, NewSlice(T)) // []T required for variadic signature
+		sig.variadic = true
+		check.arguments(x, call, sig, func(x *operand, i int) {
+			// only evaluate arguments that have not been evaluated before
+			if i < len(alist) {
+				*x = alist[i]
+				return
+			}
+			arg(x, i)
+		}, nargs)
+		// ok to continue even if check.arguments reported errors
+
+		x.mode = value
+		x.typ = S
+		if check.Types != nil {
+			check.recordBuiltinType(call.Fun, sig)
+		}
+
+	case _Cap, _Len:
+		// cap(x)
+		// len(x)
+		mode := invalid
+		var typ Type
+		var val exact.Value
+		switch typ = implicitArrayDeref(x.typ.Underlying()); t := typ.(type) {
+		case *Basic:
+			if isString(t) && id == _Len {
+				if x.mode == constant {
+					mode = constant
+					val = exact.MakeInt64(int64(len(exact.StringVal(x.val))))
+				} else {
+					mode = value
+				}
+			}
+
+		case *Array:
+			mode = value
+			// spec: "The expressions len(s) and cap(s) are constants
+			// if the type of s is an array or pointer to an array and
+			// the expression s does not contain channel receives or
+			// function calls; in this case s is not evaluated."
+			if !check.hasCallOrRecv {
+				mode = constant
+				val = exact.MakeInt64(t.len)
+			}
+
+		case *Slice, *Chan:
+			mode = value
+
+		case *Map:
+			if id == _Len {
+				mode = value
+			}
+		}
+
+		if mode == invalid {
+			check.invalidArg(x.pos(), "%s for %s", x, bin.name)
+			return
+		}
+
+		x.mode = mode
+		x.typ = Typ[Int]
+		x.val = val
+		if check.Types != nil && mode != constant {
+			check.recordBuiltinType(call.Fun, makeSig(x.typ, typ))
+		}
+
+	case _Close:
+		// close(c)
+		c, _ := x.typ.Underlying().(*Chan)
+		if c == nil {
+			check.invalidArg(x.pos(), "%s is not a channel", x)
+			return
+		}
+		if c.dir == RecvOnly {
+			check.invalidArg(x.pos(), "%s must not be a receive-only channel", x)
+			return
+		}
+
+		x.mode = novalue
+		if check.Types != nil {
+			check.recordBuiltinType(call.Fun, makeSig(nil, c))
+		}
+
+	case _Complex:
+		// complex(x, y realT) complexT
+		if !check.complexArg(x) {
+			return
+		}
+
+		var y operand
+		arg(&y, 1)
+		if y.mode == invalid {
+			return
+		}
+		if !check.complexArg(&y) {
+			return
+		}
+
+		check.convertUntyped(x, y.typ)
+		if x.mode == invalid {
+			return
+		}
+		check.convertUntyped(&y, x.typ)
+		if y.mode == invalid {
+			return
+		}
+
+		if !Identical(x.typ, y.typ) {
+			check.invalidArg(x.pos(), "mismatched types %s and %s", x.typ, y.typ)
+			return
+		}
+
+		if x.mode == constant && y.mode == constant {
+			x.val = exact.BinaryOp(x.val, token.ADD, exact.MakeImag(y.val))
+		} else {
+			x.mode = value
+		}
+
+		realT := x.typ
+		complexT := Typ[Invalid]
+		switch realT.Underlying().(*Basic).kind {
+		case Float32:
+			complexT = Typ[Complex64]
+		case Float64:
+			complexT = Typ[Complex128]
+		case UntypedInt, UntypedRune, UntypedFloat:
+			if x.mode == constant {
+				realT = defaultType(realT).(*Basic)
+				complexT = Typ[UntypedComplex]
+			} else {
+				// untyped but not constant; probably because one
+				// operand is a non-constant shift of untyped lhs
+				realT = Typ[Float64]
+				complexT = Typ[Complex128]
+			}
+		default:
+			check.invalidArg(x.pos(), "float32 or float64 arguments expected")
+			return
+		}
+
+		x.typ = complexT
+		if check.Types != nil && x.mode != constant {
+			check.recordBuiltinType(call.Fun, makeSig(complexT, realT, realT))
+		}
+
+		if x.mode != constant {
+			// The arguments have now their final types, which at run-
+			// time will be materialized. Update the expression trees.
+			// If the current types are untyped, the materialized type
+			// is the respective default type.
+			// (If the result is constant, the arguments are never
+			// materialized and there is nothing to do.)
+			check.updateExprType(x.expr, realT, true)
+			check.updateExprType(y.expr, realT, true)
+		}
+
+	case _Copy:
+		// copy(x, y []T) int
+		var dst Type
+		if t, _ := x.typ.Underlying().(*Slice); t != nil {
+			dst = t.elem
+		}
+
+		var y operand
+		arg(&y, 1)
+		if y.mode == invalid {
+			return
+		}
+		var src Type
+		switch t := y.typ.Underlying().(type) {
+		case *Basic:
+			if isString(y.typ) {
+				src = universeByte
+			}
+		case *Slice:
+			src = t.elem
+		}
+
+		if dst == nil || src == nil {
+			check.invalidArg(x.pos(), "copy expects slice arguments; found %s and %s", x, &y)
+			return
+		}
+
+		if !Identical(dst, src) {
+			check.invalidArg(x.pos(), "arguments to copy %s and %s have different element types %s and %s", x, &y, dst, src)
+			return
+		}
+
+		if check.Types != nil {
+			check.recordBuiltinType(call.Fun, makeSig(Typ[Int], x.typ, y.typ))
+		}
+		x.mode = value
+		x.typ = Typ[Int]
+
+	case _Delete:
+		// delete(m, k)
+		m, _ := x.typ.Underlying().(*Map)
+		if m == nil {
+			check.invalidArg(x.pos(), "%s is not a map", x)
+			return
+		}
+		arg(x, 1) // k
+		if x.mode == invalid {
+			return
+		}
+
+		if !x.assignableTo(check.conf, m.key) {
+			check.invalidArg(x.pos(), "%s is not assignable to %s", x, m.key)
+			return
+		}
+
+		x.mode = novalue
+		if check.Types != nil {
+			check.recordBuiltinType(call.Fun, makeSig(nil, m, m.key))
+		}
+
+	case _Imag, _Real:
+		// imag(complexT) realT
+		// real(complexT) realT
+		if !isComplex(x.typ) {
+			check.invalidArg(x.pos(), "%s must be a complex number", x)
+			return
+		}
+		if x.mode == constant {
+			if id == _Real {
+				x.val = exact.Real(x.val)
+			} else {
+				x.val = exact.Imag(x.val)
+			}
+		} else {
+			x.mode = value
+		}
+		var k BasicKind
+		switch x.typ.Underlying().(*Basic).kind {
+		case Complex64:
+			k = Float32
+		case Complex128:
+			k = Float64
+		case UntypedComplex:
+			k = UntypedFloat
+		default:
+			unreachable()
+		}
+
+		if check.Types != nil && x.mode != constant {
+			check.recordBuiltinType(call.Fun, makeSig(Typ[k], x.typ))
+		}
+		x.typ = Typ[k]
+
+	case _Make:
+		// make(T, n)
+		// make(T, n, m)
+		// (no argument evaluated yet)
+		arg0 := call.Args[0]
+		T := check.typ(arg0)
+		if T == Typ[Invalid] {
+			return
+		}
+
+		var min int // minimum number of arguments
+		switch T.Underlying().(type) {
+		case *Slice:
+			min = 2
+		case *Map, *Chan:
+			min = 1
+		default:
+			check.invalidArg(arg0.Pos(), "cannot make %s; type must be slice, map, or channel", arg0)
+			return
+		}
+		if nargs < min || min+1 < nargs {
+			check.errorf(call.Pos(), "%s expects %d or %d arguments; found %d", call, min, min+1, nargs)
+			return
+		}
+		var sizes []int64 // constant integer arguments, if any
+		for _, arg := range call.Args[1:] {
+			if s, ok := check.index(arg, -1); ok && s >= 0 {
+				sizes = append(sizes, s)
+			}
+		}
+		if len(sizes) == 2 && sizes[0] > sizes[1] {
+			check.invalidArg(call.Args[1].Pos(), "length and capacity swapped")
+			// safe to continue
+		}
+		x.mode = value
+		x.typ = T
+		if check.Types != nil {
+			params := [...]Type{T, Typ[Int], Typ[Int]}
+			check.recordBuiltinType(call.Fun, makeSig(x.typ, params[:1+len(sizes)]...))
+		}
+
+	case _New:
+		// new(T)
+		// (no argument evaluated yet)
+		T := check.typ(call.Args[0])
+		if T == Typ[Invalid] {
+			return
+		}
+
+		x.mode = value
+		x.typ = &Pointer{base: T}
+		if check.Types != nil {
+			check.recordBuiltinType(call.Fun, makeSig(x.typ, T))
+		}
+
+	case _Panic:
+		// panic(x)
+		T := new(Interface)
+		if !check.assignment(x, T) {
+			assert(x.mode == invalid)
+			return
+		}
+
+		x.mode = novalue
+		if check.Types != nil {
+			check.recordBuiltinType(call.Fun, makeSig(nil, T))
+		}
+
+	case _Print, _Println:
+		// print(x, y, ...)
+		// println(x, y, ...)
+		var params []Type
+		if nargs > 0 {
+			params = make([]Type, nargs)
+			for i := 0; i < nargs; i++ {
+				if i > 0 {
+					arg(x, i) // first argument already evaluated
+				}
+				if !check.assignment(x, nil) {
+					assert(x.mode == invalid)
+					return
+				}
+				params[i] = x.typ
+			}
+		}
+
+		x.mode = novalue
+		if check.Types != nil {
+			check.recordBuiltinType(call.Fun, makeSig(nil, params...))
+		}
+
+	case _Recover:
+		// recover() interface{}
+		x.mode = value
+		x.typ = new(Interface)
+		if check.Types != nil {
+			check.recordBuiltinType(call.Fun, makeSig(x.typ))
+		}
+
+	case _Alignof:
+		// unsafe.Alignof(x T) uintptr
+		if !check.assignment(x, nil) {
+			assert(x.mode == invalid)
+			return
+		}
+
+		x.mode = constant
+		x.val = exact.MakeInt64(check.conf.alignof(x.typ))
+		x.typ = Typ[Uintptr]
+		// result is constant - no need to record signature
+
+	case _Offsetof:
+		// unsafe.Offsetof(x T) uintptr, where x must be a selector
+		// (no argument evaluated yet)
+		arg0 := call.Args[0]
+		selx, _ := unparen(arg0).(*ast.SelectorExpr)
+		if selx == nil {
+			check.invalidArg(arg0.Pos(), "%s is not a selector expression", arg0)
+			check.use(arg0)
+			return
+		}
+
+		check.expr(x, selx.X)
+		if x.mode == invalid {
+			return
+		}
+
+		base := derefStructPtr(x.typ)
+		sel := selx.Sel.Name
+		obj, index, indirect := LookupFieldOrMethod(base, false, check.pkg, sel)
+		switch obj.(type) {
+		case nil:
+			check.invalidArg(x.pos(), "%s has no single field %s", base, sel)
+			return
+		case *Func:
+			// TODO(gri) Using derefStructPtr may result in methods being found
+			// that don't actually exist. An error either way, but the error
+			// message is confusing. See: http://play.golang.org/p/al75v23kUy ,
+			// but go/types reports: "invalid argument: x.m is a method value".
+			check.invalidArg(arg0.Pos(), "%s is a method value", arg0)
+			return
+		}
+		if indirect {
+			check.invalidArg(x.pos(), "field %s is embedded via a pointer in %s", sel, base)
+			return
+		}
+
+		// TODO(gri) Should we pass x.typ instead of base (and indirect report if derefStructPtr indirected)?
+		check.recordSelection(selx, FieldVal, base, obj, index, false)
+
+		offs := check.conf.offsetof(base, index)
+		x.mode = constant
+		x.val = exact.MakeInt64(offs)
+		x.typ = Typ[Uintptr]
+		// result is constant - no need to record signature
+
+	case _Sizeof:
+		// unsafe.Sizeof(x T) uintptr
+		if !check.assignment(x, nil) {
+			assert(x.mode == invalid)
+			return
+		}
+
+		x.mode = constant
+		x.val = exact.MakeInt64(check.conf.sizeof(x.typ))
+		x.typ = Typ[Uintptr]
+		// result is constant - no need to record signature
+
+	case _Assert:
+		// assert(pred) causes a typechecker error if pred is false.
+		// The result of assert is the value of pred if there is no error.
+		// Note: assert is only available in self-test mode.
+		if x.mode != constant || !isBoolean(x.typ) {
+			check.invalidArg(x.pos(), "%s is not a boolean constant", x)
+			return
+		}
+		if x.val.Kind() != exact.Bool {
+			check.errorf(x.pos(), "internal error: value of %s should be a boolean constant", x)
+			return
+		}
+		if !exact.BoolVal(x.val) {
+			check.errorf(call.Pos(), "%s failed", call)
+			// compile-time assertion failure - safe to continue
+		}
+		// result is constant - no need to record signature
+
+	case _Trace:
+		// trace(x, y, z, ...) dumps the positions, expressions, and
+		// values of its arguments. The result of trace is the value
+		// of the first argument.
+		// Note: trace is only available in self-test mode.
+		// (no argument evaluated yet)
+		if nargs == 0 {
+			check.dump("%s: trace() without arguments", call.Pos())
+			x.mode = novalue
+			break
+		}
+		var t operand
+		x1 := x
+		for _, arg := range call.Args {
+			check.rawExpr(x1, arg, nil) // permit trace for types, e.g.: new(trace(T))
+			check.dump("%s: %s", x1.pos(), x1)
+			x1 = &t // use incoming x only for first argument
+		}
+		// trace is only available in test mode - no need to record signature
+
+	default:
+		unreachable()
+	}
+
+	return true
+}
+
+// makeSig makes a signature for the given argument and result types.
+// Default types are used for untyped arguments, and res may be nil.
+func makeSig(res Type, args ...Type) *Signature {
+	list := make([]*Var, len(args))
+	for i, param := range args {
+		list[i] = NewVar(token.NoPos, nil, "", defaultType(param))
+	}
+	params := NewTuple(list...)
+	var result *Tuple
+	if res != nil {
+		assert(!isUntyped(res))
+		result = NewTuple(NewVar(token.NoPos, nil, "", res))
+	}
+	return &Signature{params: params, results: result}
+}
+
+// implicitArrayDeref returns A if typ is of the form *A and A is an array;
+// otherwise it returns typ.
+//
+func implicitArrayDeref(typ Type) Type {
+	if p, ok := typ.(*Pointer); ok {
+		if a, ok := p.base.Underlying().(*Array); ok {
+			return a
+		}
+	}
+	return typ
+}
+
+// unparen returns e with any enclosing parentheses stripped.
+func unparen(e ast.Expr) ast.Expr {
+	for {
+		p, ok := e.(*ast.ParenExpr)
+		if !ok {
+			return e
+		}
+		e = p.X
+	}
+}
+
+func (check *Checker) complexArg(x *operand) bool {
+	t, _ := x.typ.Underlying().(*Basic)
+	if t != nil && (t.info&IsFloat != 0 || t.kind == UntypedInt || t.kind == UntypedRune) {
+		return true
+	}
+	check.invalidArg(x.pos(), "%s must be a float32, float64, or an untyped non-complex numeric constant", x)
+	return false
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/builtins_test.go

@@ -0,0 +1,204 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types_test
+
+import (
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"testing"
+
+	_ "golang.org/x/tools/go/gcimporter"
+	. "golang.org/x/tools/go/types"
+)
+
+var builtinCalls = []struct {
+	name, src, sig string
+}{
+	{"append", `var s []int; _ = append(s)`, `func([]int, ...int) []int`},
+	{"append", `var s []int; _ = append(s, 0)`, `func([]int, ...int) []int`},
+	{"append", `var s []int; _ = (append)(s, 0)`, `func([]int, ...int) []int`},
+	{"append", `var s []byte; _ = ((append))(s, 0)`, `func([]byte, ...byte) []byte`},
+	{"append", `var s []byte; _ = append(s, "foo"...)`, `func([]byte, string...) []byte`},
+	{"append", `type T []byte; var s T; var str string; _ = append(s, str...)`, `func(p.T, string...) p.T`},
+	{"append", `type T []byte; type U string; var s T; var str U; _ = append(s, str...)`, `func(p.T, p.U...) p.T`},
+
+	{"cap", `var s [10]int; _ = cap(s)`, `invalid type`},  // constant
+	{"cap", `var s [10]int; _ = cap(&s)`, `invalid type`}, // constant
+	{"cap", `var s []int64; _ = cap(s)`, `func([]int64) int`},
+	{"cap", `var c chan<-bool; _ = cap(c)`, `func(chan<- bool) int`},
+
+	{"len", `_ = len("foo")`, `invalid type`}, // constant
+	{"len", `var s string; _ = len(s)`, `func(string) int`},
+	{"len", `var s [10]int; _ = len(s)`, `invalid type`},  // constant
+	{"len", `var s [10]int; _ = len(&s)`, `invalid type`}, // constant
+	{"len", `var s []int64; _ = len(s)`, `func([]int64) int`},
+	{"len", `var c chan<-bool; _ = len(c)`, `func(chan<- bool) int`},
+	{"len", `var m map[string]float32; _ = len(m)`, `func(map[string]float32) int`},
+
+	{"close", `var c chan int; close(c)`, `func(chan int)`},
+	{"close", `var c chan<- chan string; close(c)`, `func(chan<- chan string)`},
+
+	{"complex", `_ = complex(1, 0)`, `invalid type`}, // constant
+	{"complex", `var re float32; _ = complex(re, 1.0)`, `func(float32, float32) complex64`},
+	{"complex", `var im float64; _ = complex(1, im)`, `func(float64, float64) complex128`},
+	{"complex", `type F32 float32; var re, im F32; _ = complex(re, im)`, `func(p.F32, p.F32) complex64`},
+	{"complex", `type F64 float64; var re, im F64; _ = complex(re, im)`, `func(p.F64, p.F64) complex128`},
+
+	{"copy", `var src, dst []byte; copy(dst, src)`, `func([]byte, []byte) int`},
+	{"copy", `type T [][]int; var src, dst T; _ = copy(dst, src)`, `func(p.T, p.T) int`},
+	{"copy", `var src string; var dst []byte; copy(dst, src)`, `func([]byte, string) int`},
+	{"copy", `type T string; type U []byte; var src T; var dst U; copy(dst, src)`, `func(p.U, p.T) int`},
+	{"copy", `var dst []byte; copy(dst, "hello")`, `func([]byte, string) int`},
+
+	{"delete", `var m map[string]bool; delete(m, "foo")`, `func(map[string]bool, string)`},
+	{"delete", `type (K string; V int); var m map[K]V; delete(m, "foo")`, `func(map[p.K]p.V, p.K)`},
+
+	{"imag", `_ = imag(1i)`, `invalid type`}, // constant
+	{"imag", `var c complex64; _ = imag(c)`, `func(complex64) float32`},
+	{"imag", `var c complex128; _ = imag(c)`, `func(complex128) float64`},
+	{"imag", `type C64 complex64; var c C64; _ = imag(c)`, `func(p.C64) float32`},
+	{"imag", `type C128 complex128; var c C128; _ = imag(c)`, `func(p.C128) float64`},
+
+	{"real", `_ = real(1i)`, `invalid type`}, // constant
+	{"real", `var c complex64; _ = real(c)`, `func(complex64) float32`},
+	{"real", `var c complex128; _ = real(c)`, `func(complex128) float64`},
+	{"real", `type C64 complex64; var c C64; _ = real(c)`, `func(p.C64) float32`},
+	{"real", `type C128 complex128; var c C128; _ = real(c)`, `func(p.C128) float64`},
+
+	{"make", `_ = make([]int, 10)`, `func([]int, int) []int`},
+	{"make", `type T []byte; _ = make(T, 10, 20)`, `func(p.T, int, int) p.T`},
+
+	{"new", `_ = new(int)`, `func(int) *int`},
+	{"new", `type T struct{}; _ = new(T)`, `func(p.T) *p.T`},
+
+	{"panic", `panic(0)`, `func(interface{})`},
+	{"panic", `panic("foo")`, `func(interface{})`},
+
+	{"print", `print()`, `func()`},
+	{"print", `print(0)`, `func(int)`},
+	{"print", `print(1, 2.0, "foo", true)`, `func(int, float64, string, bool)`},
+
+	{"println", `println()`, `func()`},
+	{"println", `println(0)`, `func(int)`},
+	{"println", `println(1, 2.0, "foo", true)`, `func(int, float64, string, bool)`},
+
+	{"recover", `recover()`, `func() interface{}`},
+	{"recover", `_ = recover()`, `func() interface{}`},
+
+	{"Alignof", `_ = unsafe.Alignof(0)`, `invalid type`},                 // constant
+	{"Alignof", `var x struct{}; _ = unsafe.Alignof(x)`, `invalid type`}, // constant
+
+	{"Offsetof", `var x struct{f bool}; _ = unsafe.Offsetof(x.f)`, `invalid type`},           // constant
+	{"Offsetof", `var x struct{_ int; f bool}; _ = unsafe.Offsetof((&x).f)`, `invalid type`}, // constant
+
+	{"Sizeof", `_ = unsafe.Sizeof(0)`, `invalid type`},                 // constant
+	{"Sizeof", `var x struct{}; _ = unsafe.Sizeof(x)`, `invalid type`}, // constant
+
+	{"assert", `assert(true)`, `invalid type`},                                    // constant
+	{"assert", `type B bool; const pred B = 1 < 2; assert(pred)`, `invalid type`}, // constant
+
+	// no tests for trace since it produces output as a side-effect
+}
+
+func TestBuiltinSignatures(t *testing.T) {
+	DefPredeclaredTestFuncs()
+
+	seen := map[string]bool{"trace": true} // no test for trace built-in; add it manually
+	for _, call := range builtinCalls {
+		testBuiltinSignature(t, call.name, call.src, call.sig)
+		seen[call.name] = true
+	}
+
+	// make sure we didn't miss one
+	for _, name := range Universe.Names() {
+		if _, ok := Universe.Lookup(name).(*Builtin); ok && !seen[name] {
+			t.Errorf("missing test for %s", name)
+		}
+	}
+	for _, name := range Unsafe.Scope().Names() {
+		if _, ok := Unsafe.Scope().Lookup(name).(*Builtin); ok && !seen[name] {
+			t.Errorf("missing test for unsafe.%s", name)
+		}
+	}
+}
+
+func testBuiltinSignature(t *testing.T, name, src0, want string) {
+	src := fmt.Sprintf(`package p; import "unsafe"; type _ unsafe.Pointer /* use unsafe */; func _() { %s }`, src0)
+	f, err := parser.ParseFile(fset, "", src, 0)
+	if err != nil {
+		t.Errorf("%s: %s", src0, err)
+		return
+	}
+
+	var conf Config
+	uses := make(map[*ast.Ident]Object)
+	types := make(map[ast.Expr]TypeAndValue)
+	_, err = conf.Check(f.Name.Name, fset, []*ast.File{f}, &Info{Uses: uses, Types: types})
+	if err != nil {
+		t.Errorf("%s: %s", src0, err)
+		return
+	}
+
+	// find called function
+	n := 0
+	var fun ast.Expr
+	for x := range types {
+		if call, _ := x.(*ast.CallExpr); call != nil {
+			fun = call.Fun
+			n++
+		}
+	}
+	if n != 1 {
+		t.Errorf("%s: got %d CallExprs; want 1", src0, n)
+		return
+	}
+
+	// check recorded types for fun and descendents (may be parenthesized)
+	for {
+		// the recorded type for the built-in must match the wanted signature
+		typ := types[fun].Type
+		if typ == nil {
+			t.Errorf("%s: no type recorded for %s", src0, ExprString(fun))
+			return
+		}
+		if got := typ.String(); got != want {
+			t.Errorf("%s: got type %s; want %s", src0, got, want)
+			return
+		}
+
+		// called function must be a (possibly parenthesized, qualified)
+		// identifier denoting the expected built-in
+		switch p := fun.(type) {
+		case *ast.Ident:
+			obj := uses[p]
+			if obj == nil {
+				t.Errorf("%s: no object found for %s", src0, p)
+				return
+			}
+			bin, _ := obj.(*Builtin)
+			if bin == nil {
+				t.Errorf("%s: %s does not denote a built-in", src0, p)
+				return
+			}
+			if bin.Name() != name {
+				t.Errorf("%s: got built-in %s; want %s", src0, bin.Name(), name)
+				return
+			}
+			return // we're done
+
+		case *ast.ParenExpr:
+			fun = p.X // unpack
+
+		case *ast.SelectorExpr:
+			// built-in from package unsafe - ignore details
+			return // we're done
+
+		default:
+			t.Errorf("%s: invalid function call", src0)
+			return
+		}
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/call.go

@@ -0,0 +1,441 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements typechecking of call and selector expressions.
+
+package types
+
+import (
+	"go/ast"
+	"go/token"
+)
+
+func (check *Checker) call(x *operand, e *ast.CallExpr) exprKind {
+	check.exprOrType(x, e.Fun)
+
+	switch x.mode {
+	case invalid:
+		check.use(e.Args...)
+		x.mode = invalid
+		x.expr = e
+		return statement
+
+	case typexpr:
+		// conversion
+		T := x.typ
+		x.mode = invalid
+		switch n := len(e.Args); n {
+		case 0:
+			check.errorf(e.Rparen, "missing argument in conversion to %s", T)
+		case 1:
+			check.expr(x, e.Args[0])
+			if x.mode != invalid {
+				check.conversion(x, T)
+			}
+		default:
+			check.errorf(e.Args[n-1].Pos(), "too many arguments in conversion to %s", T)
+		}
+		x.expr = e
+		return conversion
+
+	case builtin:
+		id := x.id
+		if !check.builtin(x, e, id) {
+			x.mode = invalid
+		}
+		x.expr = e
+		// a non-constant result implies a function call
+		if x.mode != invalid && x.mode != constant {
+			check.hasCallOrRecv = true
+		}
+		return predeclaredFuncs[id].kind
+
+	default:
+		// function/method call
+		sig, _ := x.typ.Underlying().(*Signature)
+		if sig == nil {
+			check.invalidOp(x.pos(), "cannot call non-function %s", x)
+			x.mode = invalid
+			x.expr = e
+			return statement
+		}
+
+		arg, n, _ := unpack(func(x *operand, i int) { check.expr(x, e.Args[i]) }, len(e.Args), false)
+		if arg == nil {
+			x.mode = invalid
+			x.expr = e
+			return statement
+		}
+
+		check.arguments(x, e, sig, arg, n)
+
+		// determine result
+		switch sig.results.Len() {
+		case 0:
+			x.mode = novalue
+		case 1:
+			x.mode = value
+			x.typ = sig.results.vars[0].typ // unpack tuple
+		default:
+			x.mode = value
+			x.typ = sig.results
+		}
+		x.expr = e
+		check.hasCallOrRecv = true
+
+		return statement
+	}
+}
+
+// use type-checks each argument.
+// Useful to make sure expressions are evaluated
+// (and variables are "used") in the presence of other errors.
+func (check *Checker) use(arg ...ast.Expr) {
+	var x operand
+	for _, e := range arg {
+		check.rawExpr(&x, e, nil)
+	}
+}
+
+// useGetter is like use, but takes a getter instead of a list of expressions.
+// It should be called instead of use if a getter is present to avoid repeated
+// evaluation of the first argument (since the getter was likely obtained via
+// unpack, which may have evaluated the first argument already).
+func (check *Checker) useGetter(get getter, n int) {
+	var x operand
+	for i := 0; i < n; i++ {
+		get(&x, i)
+	}
+}
+
+// A getter sets x as the i'th operand, where 0 <= i < n and n is the total
+// number of operands (context-specific, and maintained elsewhere). A getter
+// type-checks the i'th operand; the details of the actual check are getter-
+// specific.
+type getter func(x *operand, i int)
+
+// unpack takes a getter get and a number of operands n. If n == 1, unpack
+// calls the incoming getter for the first operand. If that operand is
+// invalid, unpack returns (nil, 0, false). Otherwise, if that operand is a
+// function call, or a comma-ok expression and allowCommaOk is set, the result
+// is a new getter and operand count providing access to the function results,
+// or comma-ok values, respectively. The third result value reports if it
+// is indeed the comma-ok case. In all other cases, the incoming getter and
+// operand count are returned unchanged, and the third result value is false.
+//
+// In other words, if there's exactly one operand that - after type-checking
+// by calling get - stands for multiple operands, the resulting getter provides
+// access to those operands instead.
+//
+// If the returned getter is called at most once for a given operand index i
+// (including i == 0), that operand is guaranteed to cause only one call of
+// the incoming getter with that i.
+//
+func unpack(get getter, n int, allowCommaOk bool) (getter, int, bool) {
+	if n == 1 {
+		// possibly result of an n-valued function call or comma,ok value
+		var x0 operand
+		get(&x0, 0)
+		if x0.mode == invalid {
+			return nil, 0, false
+		}
+
+		if t, ok := x0.typ.(*Tuple); ok {
+			// result of an n-valued function call
+			return func(x *operand, i int) {
+				x.mode = value
+				x.expr = x0.expr
+				x.typ = t.At(i).typ
+			}, t.Len(), false
+		}
+
+		if x0.mode == mapindex || x0.mode == commaok {
+			// comma-ok value
+			if allowCommaOk {
+				a := [2]Type{x0.typ, Typ[UntypedBool]}
+				return func(x *operand, i int) {
+					x.mode = value
+					x.expr = x0.expr
+					x.typ = a[i]
+				}, 2, true
+			}
+			x0.mode = value
+		}
+
+		// single value
+		return func(x *operand, i int) {
+			if i != 0 {
+				unreachable()
+			}
+			*x = x0
+		}, 1, false
+	}
+
+	// zero or multiple values
+	return get, n, false
+}
+
+// arguments checks argument passing for the call with the given signature.
+// The arg function provides the operand for the i'th argument.
+func (check *Checker) arguments(x *operand, call *ast.CallExpr, sig *Signature, arg getter, n int) {
+	if call.Ellipsis.IsValid() {
+		// last argument is of the form x...
+		if len(call.Args) == 1 && n > 1 {
+			// f()... is not permitted if f() is multi-valued
+			check.errorf(call.Ellipsis, "cannot use ... with %d-valued expression %s", n, call.Args[0])
+			check.useGetter(arg, n)
+			return
+		}
+		if !sig.variadic {
+			check.errorf(call.Ellipsis, "cannot use ... in call to non-variadic %s", call.Fun)
+			check.useGetter(arg, n)
+			return
+		}
+	}
+
+	// evaluate arguments
+	for i := 0; i < n; i++ {
+		arg(x, i)
+		if x.mode != invalid {
+			var ellipsis token.Pos
+			if i == n-1 && call.Ellipsis.IsValid() {
+				ellipsis = call.Ellipsis
+			}
+			check.argument(sig, i, x, ellipsis)
+		}
+	}
+
+	// check argument count
+	if sig.variadic {
+		// a variadic function accepts an "empty"
+		// last argument: count one extra
+		n++
+	}
+	if n < sig.params.Len() {
+		check.errorf(call.Rparen, "too few arguments in call to %s", call.Fun)
+		// ok to continue
+	}
+}
+
+// argument checks passing of argument x to the i'th parameter of the given signature.
+// If ellipsis is valid, the argument is followed by ... at that position in the call.
+func (check *Checker) argument(sig *Signature, i int, x *operand, ellipsis token.Pos) {
+	n := sig.params.Len()
+
+	// determine parameter type
+	var typ Type
+	switch {
+	case i < n:
+		typ = sig.params.vars[i].typ
+	case sig.variadic:
+		typ = sig.params.vars[n-1].typ
+		if debug {
+			if _, ok := typ.(*Slice); !ok {
+				check.dump("%s: expected unnamed slice type, got %s", sig.params.vars[n-1].Pos(), typ)
+			}
+		}
+	default:
+		check.errorf(x.pos(), "too many arguments")
+		return
+	}
+
+	if ellipsis.IsValid() {
+		// argument is of the form x...
+		if i != n-1 {
+			check.errorf(ellipsis, "can only use ... with matching parameter")
+			return
+		}
+		switch t := x.typ.Underlying().(type) {
+		case *Slice:
+			// ok
+		case *Tuple:
+			check.errorf(ellipsis, "cannot use ... with %d-valued expression %s", t.Len(), x)
+			return
+		default:
+			check.errorf(x.pos(), "cannot use %s as parameter of type %s", x, typ)
+			return
+		}
+	} else if sig.variadic && i >= n-1 {
+		// use the variadic parameter slice's element type
+		typ = typ.(*Slice).elem
+	}
+
+	if !check.assignment(x, typ) && x.mode != invalid {
+		check.errorf(x.pos(), "cannot pass argument %s to parameter of type %s", x, typ)
+	}
+}
+
+func (check *Checker) selector(x *operand, e *ast.SelectorExpr) {
+	// these must be declared before the "goto Error" statements
+	var (
+		obj      Object
+		index    []int
+		indirect bool
+	)
+
+	sel := e.Sel.Name
+	// If the identifier refers to a package, handle everything here
+	// so we don't need a "package" mode for operands: package names
+	// can only appear in qualified identifiers which are mapped to
+	// selector expressions.
+	if ident, ok := e.X.(*ast.Ident); ok {
+		_, obj := check.scope.LookupParent(ident.Name, check.pos)
+		if pkg, _ := obj.(*PkgName); pkg != nil {
+			assert(pkg.pkg == check.pkg)
+			check.recordUse(ident, pkg)
+			pkg.used = true
+			exp := pkg.imported.scope.Lookup(sel)
+			if exp == nil {
+				if !pkg.imported.fake {
+					check.errorf(e.Pos(), "%s not declared by package %s", sel, ident)
+				}
+				goto Error
+			}
+			if !exp.Exported() {
+				check.errorf(e.Pos(), "%s not exported by package %s", sel, ident)
+				// ok to continue
+			}
+			check.recordUse(e.Sel, exp)
+			// Simplified version of the code for *ast.Idents:
+			// - imported objects are always fully initialized
+			switch exp := exp.(type) {
+			case *Const:
+				assert(exp.Val() != nil)
+				x.mode = constant
+				x.typ = exp.typ
+				x.val = exp.val
+			case *TypeName:
+				x.mode = typexpr
+				x.typ = exp.typ
+			case *Var:
+				x.mode = variable
+				x.typ = exp.typ
+			case *Func:
+				x.mode = value
+				x.typ = exp.typ
+			case *Builtin:
+				x.mode = builtin
+				x.typ = exp.typ
+				x.id = exp.id
+			default:
+				unreachable()
+			}
+			x.expr = e
+			return
+		}
+	}
+
+	check.exprOrType(x, e.X)
+	if x.mode == invalid {
+		goto Error
+	}
+
+	obj, index, indirect = LookupFieldOrMethod(x.typ, x.mode == variable, check.pkg, sel)
+	if obj == nil {
+		switch {
+		case index != nil:
+			// TODO(gri) should provide actual type where the conflict happens
+			check.invalidOp(e.Pos(), "ambiguous selector %s", sel)
+		case indirect:
+			check.invalidOp(e.Pos(), "%s is not in method set of %s", sel, x.typ)
+		default:
+			check.invalidOp(e.Pos(), "%s has no field or method %s", x, sel)
+		}
+		goto Error
+	}
+
+	if x.mode == typexpr {
+		// method expression
+		m, _ := obj.(*Func)
+		if m == nil {
+			check.invalidOp(e.Pos(), "%s has no method %s", x, sel)
+			goto Error
+		}
+
+		check.recordSelection(e, MethodExpr, x.typ, m, index, indirect)
+
+		// the receiver type becomes the type of the first function
+		// argument of the method expression's function type
+		var params []*Var
+		sig := m.typ.(*Signature)
+		if sig.params != nil {
+			params = sig.params.vars
+		}
+		x.mode = value
+		x.typ = &Signature{
+			params:   NewTuple(append([]*Var{NewVar(token.NoPos, check.pkg, "", x.typ)}, params...)...),
+			results:  sig.results,
+			variadic: sig.variadic,
+		}
+
+		check.addDeclDep(m)
+
+	} else {
+		// regular selector
+		switch obj := obj.(type) {
+		case *Var:
+			check.recordSelection(e, FieldVal, x.typ, obj, index, indirect)
+			if x.mode == variable || indirect {
+				x.mode = variable
+			} else {
+				x.mode = value
+			}
+			x.typ = obj.typ
+
+		case *Func:
+			// TODO(gri) If we needed to take into account the receiver's
+			// addressability, should we report the type &(x.typ) instead?
+			check.recordSelection(e, MethodVal, x.typ, obj, index, indirect)
+
+			if debug {
+				// Verify that LookupFieldOrMethod and MethodSet.Lookup agree.
+				typ := x.typ
+				if x.mode == variable {
+					// If typ is not an (unnamed) pointer or an interface,
+					// use *typ instead, because the method set of *typ
+					// includes the methods of typ.
+					// Variables are addressable, so we can always take their
+					// address.
+					if _, ok := typ.(*Pointer); !ok && !IsInterface(typ) {
+						typ = &Pointer{base: typ}
+					}
+				}
+				// If we created a synthetic pointer type above, we will throw
+				// away the method set computed here after use.
+				// TODO(gri) Method set computation should probably always compute
+				// both, the value and the pointer receiver method set and represent
+				// them in a single structure.
+				// TODO(gri) Consider also using a method set cache for the lifetime
+				// of checker once we rely on MethodSet lookup instead of individual
+				// lookup.
+				mset := NewMethodSet(typ)
+				if m := mset.Lookup(check.pkg, sel); m == nil || m.obj != obj {
+					check.dump("%s: (%s).%v -> %s", e.Pos(), typ, obj.name, m)
+					check.dump("%s\n", mset)
+					panic("method sets and lookup don't agree")
+				}
+			}
+
+			x.mode = value
+
+			// remove receiver
+			sig := *obj.typ.(*Signature)
+			sig.recv = nil
+			x.typ = &sig
+
+			check.addDeclDep(obj)
+
+		default:
+			unreachable()
+		}
+	}
+
+	// everything went well
+	x.expr = e
+	return
+
+Error:
+	x.mode = invalid
+	x.expr = e
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/check.go

@@ -0,0 +1,364 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements the Check function, which drives type-checking.
+
+package types
+
+import (
+	"go/ast"
+	"go/token"
+
+	"golang.org/x/tools/go/exact"
+)
+
+// debugging/development support
+const (
+	debug = false // leave on during development
+	trace = false // turn on for detailed type resolution traces
+)
+
+// If Strict is set, the type-checker enforces additional
+// rules not specified by the Go 1 spec, but which will
+// catch guaranteed run-time errors if the respective
+// code is executed. In other words, programs passing in
+// Strict mode are Go 1 compliant, but not all Go 1 programs
+// will pass in Strict mode. The additional rules are:
+//
+// - A type assertion x.(T) where T is an interface type
+//   is invalid if any (statically known) method that exists
+//   for both x and T have different signatures.
+//
+const strict = false
+
+// exprInfo stores information about an untyped expression.
+type exprInfo struct {
+	isLhs bool // expression is lhs operand of a shift with delayed type-check
+	mode  operandMode
+	typ   *Basic
+	val   exact.Value // constant value; or nil (if not a constant)
+}
+
+// funcInfo stores the information required for type-checking a function.
+type funcInfo struct {
+	name string    // for debugging/tracing only
+	decl *declInfo // for cycle detection
+	sig  *Signature
+	body *ast.BlockStmt
+}
+
+// A context represents the context within which an object is type-checked.
+type context struct {
+	decl          *declInfo   // package-level declaration whose init expression/function body is checked
+	scope         *Scope      // top-most scope for lookups
+	iota          exact.Value // value of iota in a constant declaration; nil otherwise
+	sig           *Signature  // function signature if inside a function; nil otherwise
+	hasLabel      bool        // set if a function makes use of labels (only ~1% of functions); unused outside functions
+	hasCallOrRecv bool        // set if an expression contains a function call or channel receive operation
+}
+
+// A Checker maintains the state of the type checker.
+// It must be created with NewChecker.
+type Checker struct {
+	// package information
+	// (initialized by NewChecker, valid for the life-time of checker)
+	conf *Config
+	fset *token.FileSet
+	pkg  *Package
+	*Info
+	objMap map[Object]*declInfo // maps package-level object to declaration info
+
+	// information collected during type-checking of a set of package files
+	// (initialized by Files, valid only for the duration of check.Files;
+	// maps and lists are allocated on demand)
+	files            []*ast.File                       // package files
+	unusedDotImports map[*Scope]map[*Package]token.Pos // positions of unused dot-imported packages for each file scope
+
+	firstErr error                 // first error encountered
+	methods  map[string][]*Func    // maps type names to associated methods
+	untyped  map[ast.Expr]exprInfo // map of expressions without final type
+	funcs    []funcInfo            // list of functions to type-check
+	delayed  []func()              // delayed checks requiring fully setup types
+
+	// context within which the current object is type-checked
+	// (valid only for the duration of type-checking a specific object)
+	context
+	pos token.Pos // if valid, identifiers are looked up as if at position pos (used by Eval)
+
+	// debugging
+	indent int // indentation for tracing
+}
+
+// addUnusedImport adds the position of a dot-imported package
+// pkg to the map of dot imports for the given file scope.
+func (check *Checker) addUnusedDotImport(scope *Scope, pkg *Package, pos token.Pos) {
+	mm := check.unusedDotImports
+	if mm == nil {
+		mm = make(map[*Scope]map[*Package]token.Pos)
+		check.unusedDotImports = mm
+	}
+	m := mm[scope]
+	if m == nil {
+		m = make(map[*Package]token.Pos)
+		mm[scope] = m
+	}
+	m[pkg] = pos
+}
+
+// addDeclDep adds the dependency edge (check.decl -> to) if check.decl exists
+func (check *Checker) addDeclDep(to Object) {
+	from := check.decl
+	if from == nil {
+		return // not in a package-level init expression
+	}
+	if _, found := check.objMap[to]; !found {
+		return // to is not a package-level object
+	}
+	from.addDep(to)
+}
+
+func (check *Checker) assocMethod(tname string, meth *Func) {
+	m := check.methods
+	if m == nil {
+		m = make(map[string][]*Func)
+		check.methods = m
+	}
+	m[tname] = append(m[tname], meth)
+}
+
+func (check *Checker) rememberUntyped(e ast.Expr, lhs bool, mode operandMode, typ *Basic, val exact.Value) {
+	m := check.untyped
+	if m == nil {
+		m = make(map[ast.Expr]exprInfo)
+		check.untyped = m
+	}
+	m[e] = exprInfo{lhs, mode, typ, val}
+}
+
+func (check *Checker) later(name string, decl *declInfo, sig *Signature, body *ast.BlockStmt) {
+	check.funcs = append(check.funcs, funcInfo{name, decl, sig, body})
+}
+
+func (check *Checker) delay(f func()) {
+	check.delayed = append(check.delayed, f)
+}
+
+// NewChecker returns a new Checker instance for a given package.
+// Package files may be added incrementally via checker.Files.
+func NewChecker(conf *Config, fset *token.FileSet, pkg *Package, info *Info) *Checker {
+	// make sure we have a configuration
+	if conf == nil {
+		conf = new(Config)
+	}
+
+	// make sure we have a package canonicalization map
+	if conf.Packages == nil {
+		conf.Packages = make(map[string]*Package)
+	}
+
+	// make sure we have an info struct
+	if info == nil {
+		info = new(Info)
+	}
+
+	return &Checker{
+		conf:   conf,
+		fset:   fset,
+		pkg:    pkg,
+		Info:   info,
+		objMap: make(map[Object]*declInfo),
+	}
+}
+
+// initFiles initializes the files-specific portion of checker.
+// The provided files must all belong to the same package.
+func (check *Checker) initFiles(files []*ast.File) {
+	// start with a clean slate (check.Files may be called multiple times)
+	check.files = nil
+	check.unusedDotImports = nil
+
+	check.firstErr = nil
+	check.methods = nil
+	check.untyped = nil
+	check.funcs = nil
+	check.delayed = nil
+
+	// determine package name and collect valid files
+	pkg := check.pkg
+	for _, file := range files {
+		switch name := file.Name.Name; pkg.name {
+		case "":
+			if name != "_" {
+				pkg.name = name
+			} else {
+				check.errorf(file.Name.Pos(), "invalid package name _")
+			}
+			fallthrough
+
+		case name:
+			check.files = append(check.files, file)
+
+		default:
+			check.errorf(file.Package, "package %s; expected %s", name, pkg.name)
+			// ignore this file
+		}
+	}
+}
+
+// A bailout panic is used for early termination.
+type bailout struct{}
+
+func (check *Checker) handleBailout(err *error) {
+	switch p := recover().(type) {
+	case nil, bailout:
+		// normal return or early exit
+		*err = check.firstErr
+	default:
+		// re-panic
+		panic(p)
+	}
+}
+
+// Files checks the provided files as part of the checker's package.
+func (check *Checker) Files(files []*ast.File) (err error) {
+	defer check.handleBailout(&err)
+
+	check.initFiles(files)
+
+	check.collectObjects()
+
+	check.packageObjects(check.resolveOrder())
+
+	check.functionBodies()
+
+	check.initOrder()
+
+	if !check.conf.DisableUnusedImportCheck {
+		check.unusedImports()
+	}
+
+	// perform delayed checks
+	for _, f := range check.delayed {
+		f()
+	}
+
+	check.recordUntyped()
+
+	check.pkg.complete = true
+	return
+}
+
+func (check *Checker) recordUntyped() {
+	if !debug && check.Types == nil {
+		return // nothing to do
+	}
+
+	for x, info := range check.untyped {
+		if debug && isTyped(info.typ) {
+			check.dump("%s: %s (type %s) is typed", x.Pos(), x, info.typ)
+			unreachable()
+		}
+		check.recordTypeAndValue(x, info.mode, info.typ, info.val)
+	}
+}
+
+func (check *Checker) recordTypeAndValue(x ast.Expr, mode operandMode, typ Type, val exact.Value) {
+	assert(x != nil)
+	assert(typ != nil)
+	if mode == invalid {
+		return // omit
+	}
+	assert(typ != nil)
+	if mode == constant {
+		assert(val != nil)
+		assert(typ == Typ[Invalid] || isConstType(typ))
+	}
+	if m := check.Types; m != nil {
+		m[x] = TypeAndValue{mode, typ, val}
+	}
+}
+
+func (check *Checker) recordBuiltinType(f ast.Expr, sig *Signature) {
+	// f must be a (possibly parenthesized) identifier denoting a built-in
+	// (built-ins in package unsafe always produce a constant result and
+	// we don't record their signatures, so we don't see qualified idents
+	// here): record the signature for f and possible children.
+	for {
+		check.recordTypeAndValue(f, builtin, sig, nil)
+		switch p := f.(type) {
+		case *ast.Ident:
+			return // we're done
+		case *ast.ParenExpr:
+			f = p.X
+		default:
+			unreachable()
+		}
+	}
+}
+
+func (check *Checker) recordCommaOkTypes(x ast.Expr, a [2]Type) {
+	assert(x != nil)
+	if a[0] == nil || a[1] == nil {
+		return
+	}
+	assert(isTyped(a[0]) && isTyped(a[1]) && isBoolean(a[1]))
+	if m := check.Types; m != nil {
+		for {
+			tv := m[x]
+			assert(tv.Type != nil) // should have been recorded already
+			pos := x.Pos()
+			tv.Type = NewTuple(
+				NewVar(pos, check.pkg, "", a[0]),
+				NewVar(pos, check.pkg, "", a[1]),
+			)
+			m[x] = tv
+			// if x is a parenthesized expression (p.X), update p.X
+			p, _ := x.(*ast.ParenExpr)
+			if p == nil {
+				break
+			}
+			x = p.X
+		}
+	}
+}
+
+func (check *Checker) recordDef(id *ast.Ident, obj Object) {
+	assert(id != nil)
+	if m := check.Defs; m != nil {
+		m[id] = obj
+	}
+}
+
+func (check *Checker) recordUse(id *ast.Ident, obj Object) {
+	assert(id != nil)
+	assert(obj != nil)
+	if m := check.Uses; m != nil {
+		m[id] = obj
+	}
+}
+
+func (check *Checker) recordImplicit(node ast.Node, obj Object) {
+	assert(node != nil)
+	assert(obj != nil)
+	if m := check.Implicits; m != nil {
+		m[node] = obj
+	}
+}
+
+func (check *Checker) recordSelection(x *ast.SelectorExpr, kind SelectionKind, recv Type, obj Object, index []int, indirect bool) {
+	assert(obj != nil && (recv == nil || len(index) > 0))
+	check.recordUse(x.Sel, obj)
+	// TODO(gri) Should we also call recordTypeAndValue?
+	if m := check.Selections; m != nil {
+		m[x] = &Selection{kind, recv, obj, index, indirect}
+	}
+}
+
+func (check *Checker) recordScope(node ast.Node, scope *Scope) {
+	assert(node != nil)
+	assert(scope != nil)
+	if m := check.Scopes; m != nil {
+		m[node] = scope
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/check_test.go

@@ -0,0 +1,296 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements a typechecker test harness. The packages specified
+// in tests are typechecked. Error messages reported by the typechecker are
+// compared against the error messages expected in the test files.
+//
+// Expected errors are indicated in the test files by putting a comment
+// of the form /* ERROR "rx" */ immediately following an offending token.
+// The harness will verify that an error matching the regular expression
+// rx is reported at that source position. Consecutive comments may be
+// used to indicate multiple errors for the same token position.
+//
+// For instance, the following test file indicates that a "not declared"
+// error should be reported for the undeclared variable x:
+//
+//	package p
+//	func f() {
+//		_ = x /* ERROR "not declared" */ + 1
+//	}
+
+// TODO(gri) Also collect strict mode errors of the form /* STRICT ... */
+//           and test against strict mode.
+
+package types_test
+
+import (
+	"flag"
+	"go/ast"
+	"go/parser"
+	"go/scanner"
+	"go/token"
+	"io/ioutil"
+	"regexp"
+	"strings"
+	"testing"
+
+	_ "golang.org/x/tools/go/gcimporter"
+	. "golang.org/x/tools/go/types"
+)
+
+var (
+	listErrors = flag.Bool("list", false, "list errors")
+	testFiles  = flag.String("files", "", "space-separated list of test files")
+)
+
+// The test filenames do not end in .go so that they are invisible
+// to gofmt since they contain comments that must not change their
+// positions relative to surrounding tokens.
+
+// Each tests entry is list of files belonging to the same package.
+var tests = [][]string{
+	{"testdata/errors.src"},
+	{"testdata/importdecl0a.src", "testdata/importdecl0b.src"},
+	{"testdata/importdecl1a.src", "testdata/importdecl1b.src"},
+	{"testdata/cycles.src"},
+	{"testdata/cycles1.src"},
+	{"testdata/cycles2.src"},
+	{"testdata/cycles3.src"},
+	{"testdata/cycles4.src"},
+	{"testdata/init0.src"},
+	{"testdata/init1.src"},
+	{"testdata/init2.src"},
+	{"testdata/decls0.src"},
+	{"testdata/decls1.src"},
+	{"testdata/decls2a.src", "testdata/decls2b.src"},
+	{"testdata/decls3.src"},
+	{"testdata/const0.src"},
+	{"testdata/const1.src"},
+	{"testdata/constdecl.src"},
+	{"testdata/vardecl.src"},
+	{"testdata/expr0.src"},
+	{"testdata/expr1.src"},
+	{"testdata/expr2.src"},
+	{"testdata/expr3.src"},
+	{"testdata/methodsets.src"},
+	{"testdata/shifts.src"},
+	{"testdata/builtins.src"},
+	{"testdata/conversions.src"},
+	{"testdata/stmt0.src"},
+	{"testdata/stmt1.src"},
+	{"testdata/gotos.src"},
+	{"testdata/labels.src"},
+	{"testdata/issues.src"},
+	{"testdata/blank.src"},
+}
+
+var fset = token.NewFileSet()
+
+// Positioned errors are of the form filename:line:column: message .
+var posMsgRx = regexp.MustCompile(`^(.*:[0-9]+:[0-9]+): *(.*)`)
+
+// splitError splits an error's error message into a position string
+// and the actual error message. If there's no position information,
+// pos is the empty string, and msg is the entire error message.
+//
+func splitError(err error) (pos, msg string) {
+	msg = err.Error()
+	if m := posMsgRx.FindStringSubmatch(msg); len(m) == 3 {
+		pos = m[1]
+		msg = m[2]
+	}
+	return
+}
+
+func parseFiles(t *testing.T, filenames []string) ([]*ast.File, []error) {
+	var files []*ast.File
+	var errlist []error
+	for _, filename := range filenames {
+		file, err := parser.ParseFile(fset, filename, nil, parser.AllErrors)
+		if file == nil {
+			t.Fatalf("%s: %s", filename, err)
+		}
+		files = append(files, file)
+		if err != nil {
+			if list, _ := err.(scanner.ErrorList); len(list) > 0 {
+				for _, err := range list {
+					errlist = append(errlist, err)
+				}
+			} else {
+				errlist = append(errlist, err)
+			}
+		}
+	}
+	return files, errlist
+}
+
+// ERROR comments must start with text `ERROR "rx"` or `ERROR rx` where
+// rx is a regular expression that matches the expected error message.
+// Space around "rx" or rx is ignored. Use the form `ERROR HERE "rx"`
+// for error messages that are located immediately after rather than
+// at a token's position.
+//
+var errRx = regexp.MustCompile(`^ *ERROR *(HERE)? *"?([^"]*)"?`)
+
+// errMap collects the regular expressions of ERROR comments found
+// in files and returns them as a map of error positions to error messages.
+//
+func errMap(t *testing.T, testname string, files []*ast.File) map[string][]string {
+	// map of position strings to lists of error message patterns
+	errmap := make(map[string][]string)
+
+	for _, file := range files {
+		filename := fset.Position(file.Package).Filename
+		src, err := ioutil.ReadFile(filename)
+		if err != nil {
+			t.Fatalf("%s: could not read %s", testname, filename)
+		}
+
+		var s scanner.Scanner
+		s.Init(fset.AddFile(filename, -1, len(src)), src, nil, scanner.ScanComments)
+		var prev token.Pos // position of last non-comment, non-semicolon token
+		var here token.Pos // position immediately after the token at position prev
+
+	scanFile:
+		for {
+			pos, tok, lit := s.Scan()
+			switch tok {
+			case token.EOF:
+				break scanFile
+			case token.COMMENT:
+				if lit[1] == '*' {
+					lit = lit[:len(lit)-2] // strip trailing */
+				}
+				if s := errRx.FindStringSubmatch(lit[2:]); len(s) == 3 {
+					pos := prev
+					if s[1] == "HERE" {
+						pos = here
+					}
+					p := fset.Position(pos).String()
+					errmap[p] = append(errmap[p], strings.TrimSpace(s[2]))
+				}
+			case token.SEMICOLON:
+				// ignore automatically inserted semicolon
+				if lit == "\n" {
+					continue scanFile
+				}
+				fallthrough
+			default:
+				prev = pos
+				var l int // token length
+				if tok.IsLiteral() {
+					l = len(lit)
+				} else {
+					l = len(tok.String())
+				}
+				here = prev + token.Pos(l)
+			}
+		}
+	}
+
+	return errmap
+}
+
+func eliminate(t *testing.T, errmap map[string][]string, errlist []error) {
+	for _, err := range errlist {
+		pos, gotMsg := splitError(err)
+		list := errmap[pos]
+		index := -1 // list index of matching message, if any
+		// we expect one of the messages in list to match the error at pos
+		for i, wantRx := range list {
+			rx, err := regexp.Compile(wantRx)
+			if err != nil {
+				t.Errorf("%s: %v", pos, err)
+				continue
+			}
+			if rx.MatchString(gotMsg) {
+				index = i
+				break
+			}
+		}
+		if index >= 0 {
+			// eliminate from list
+			if n := len(list) - 1; n > 0 {
+				// not the last entry - swap in last element and shorten list by 1
+				list[index] = list[n]
+				errmap[pos] = list[:n]
+			} else {
+				// last entry - remove list from map
+				delete(errmap, pos)
+			}
+		} else {
+			t.Errorf("%s: no error expected: %q", pos, gotMsg)
+		}
+	}
+}
+
+func checkFiles(t *testing.T, testfiles []string) {
+	// parse files and collect parser errors
+	files, errlist := parseFiles(t, testfiles)
+
+	pkgName := "<no package>"
+	if len(files) > 0 {
+		pkgName = files[0].Name.Name
+	}
+
+	if *listErrors && len(errlist) > 0 {
+		t.Errorf("--- %s:", pkgName)
+		for _, err := range errlist {
+			t.Error(err)
+		}
+	}
+
+	// typecheck and collect typechecker errors
+	var conf Config
+	conf.Error = func(err error) {
+		if *listErrors {
+			t.Error(err)
+			return
+		}
+		// Ignore secondary error messages starting with "\t";
+		// they are clarifying messages for a primary error.
+		if !strings.Contains(err.Error(), ": \t") {
+			errlist = append(errlist, err)
+		}
+	}
+	conf.Check(pkgName, fset, files, nil)
+
+	if *listErrors {
+		return
+	}
+
+	// match and eliminate errors;
+	// we are expecting the following errors
+	errmap := errMap(t, pkgName, files)
+	eliminate(t, errmap, errlist)
+
+	// there should be no expected errors left
+	if len(errmap) > 0 {
+		t.Errorf("--- %s: %d source positions with expected (but not reported) errors:", pkgName, len(errmap))
+		for pos, list := range errmap {
+			for _, rx := range list {
+				t.Errorf("%s: %q", pos, rx)
+			}
+		}
+	}
+}
+
+func TestCheck(t *testing.T) {
+	skipSpecialPlatforms(t)
+
+	// Declare builtins for testing.
+	DefPredeclaredTestFuncs()
+
+	// If explicit test files are specified, only check those.
+	if files := *testFiles; files != "" {
+		checkFiles(t, strings.Split(files, " "))
+		return
+	}
+
+	// Otherwise, run all the tests.
+	for _, files := range tests {
+		checkFiles(t, files)
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/conversions.go

@@ -0,0 +1,146 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements typechecking of conversions.
+
+package types
+
+import "golang.org/x/tools/go/exact"
+
+// Conversion type-checks the conversion T(x).
+// The result is in x.
+func (check *Checker) conversion(x *operand, T Type) {
+	constArg := x.mode == constant
+
+	var ok bool
+	switch {
+	case constArg && isConstType(T):
+		// constant conversion
+		switch t := T.Underlying().(*Basic); {
+		case representableConst(x.val, check.conf, t.kind, &x.val):
+			ok = true
+		case isInteger(x.typ) && isString(t):
+			codepoint := int64(-1)
+			if i, ok := exact.Int64Val(x.val); ok {
+				codepoint = i
+			}
+			// If codepoint < 0 the absolute value is too large (or unknown) for
+			// conversion. This is the same as converting any other out-of-range
+			// value - let string(codepoint) do the work.
+			x.val = exact.MakeString(string(codepoint))
+			ok = true
+		}
+	case x.convertibleTo(check.conf, T):
+		// non-constant conversion
+		x.mode = value
+		ok = true
+	}
+
+	if !ok {
+		check.errorf(x.pos(), "cannot convert %s to %s", x, T)
+		x.mode = invalid
+		return
+	}
+
+	// The conversion argument types are final. For untyped values the
+	// conversion provides the type, per the spec: "A constant may be
+	// given a type explicitly by a constant declaration or conversion,...".
+	final := x.typ
+	if isUntyped(x.typ) {
+		final = T
+		// - For conversions to interfaces, use the argument's default type.
+		// - For conversions of untyped constants to non-constant types, also
+		//   use the default type (e.g., []byte("foo") should report string
+		//   not []byte as type for the constant "foo").
+		// - Keep untyped nil for untyped nil arguments.
+		if IsInterface(T) || constArg && !isConstType(T) {
+			final = defaultType(x.typ)
+		}
+		check.updateExprType(x.expr, final, true)
+	}
+
+	x.typ = T
+}
+
+func (x *operand) convertibleTo(conf *Config, T Type) bool {
+	// "x is assignable to T"
+	if x.assignableTo(conf, T) {
+		return true
+	}
+
+	// "x's type and T have identical underlying types"
+	V := x.typ
+	Vu := V.Underlying()
+	Tu := T.Underlying()
+	if Identical(Vu, Tu) {
+		return true
+	}
+
+	// "x's type and T are unnamed pointer types and their pointer base types have identical underlying types"
+	if V, ok := V.(*Pointer); ok {
+		if T, ok := T.(*Pointer); ok {
+			if Identical(V.base.Underlying(), T.base.Underlying()) {
+				return true
+			}
+		}
+	}
+
+	// "x's type and T are both integer or floating point types"
+	if (isInteger(V) || isFloat(V)) && (isInteger(T) || isFloat(T)) {
+		return true
+	}
+
+	// "x's type and T are both complex types"
+	if isComplex(V) && isComplex(T) {
+		return true
+	}
+
+	// "x is an integer or a slice of bytes or runes and T is a string type"
+	if (isInteger(V) || isBytesOrRunes(Vu)) && isString(T) {
+		return true
+	}
+
+	// "x is a string and T is a slice of bytes or runes"
+	if isString(V) && isBytesOrRunes(Tu) {
+		return true
+	}
+
+	// package unsafe:
+	// "any pointer or value of underlying type uintptr can be converted into a unsafe.Pointer"
+	if (isPointer(Vu) || isUintptr(Vu)) && isUnsafePointer(T) {
+		return true
+	}
+	// "and vice versa"
+	if isUnsafePointer(V) && (isPointer(Tu) || isUintptr(Tu)) {
+		return true
+	}
+
+	return false
+}
+
+func isUintptr(typ Type) bool {
+	t, ok := typ.Underlying().(*Basic)
+	return ok && t.kind == Uintptr
+}
+
+func isUnsafePointer(typ Type) bool {
+	// TODO(gri): Is this (typ.Underlying() instead of just typ) correct?
+	//            The spec does not say so, but gc claims it is. See also
+	//            issue 6326.
+	t, ok := typ.Underlying().(*Basic)
+	return ok && t.kind == UnsafePointer
+}
+
+func isPointer(typ Type) bool {
+	_, ok := typ.Underlying().(*Pointer)
+	return ok
+}
+
+func isBytesOrRunes(typ Type) bool {
+	if s, ok := typ.(*Slice); ok {
+		t, ok := s.elem.Underlying().(*Basic)
+		return ok && (t.kind == Byte || t.kind == Rune)
+	}
+	return false
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/decl.go

@@ -0,0 +1,431 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types
+
+import (
+	"go/ast"
+	"go/token"
+
+	"golang.org/x/tools/go/exact"
+)
+
+func (check *Checker) reportAltDecl(obj Object) {
+	if pos := obj.Pos(); pos.IsValid() {
+		// We use "other" rather than "previous" here because
+		// the first declaration seen may not be textually
+		// earlier in the source.
+		check.errorf(pos, "\tother declaration of %s", obj.Name()) // secondary error, \t indented
+	}
+}
+
+func (check *Checker) declare(scope *Scope, id *ast.Ident, obj Object, pos token.Pos) {
+	// spec: "The blank identifier, represented by the underscore
+	// character _, may be used in a declaration like any other
+	// identifier but the declaration does not introduce a new
+	// binding."
+	if obj.Name() != "_" {
+		if alt := scope.Insert(obj); alt != nil {
+			check.errorf(obj.Pos(), "%s redeclared in this block", obj.Name())
+			check.reportAltDecl(alt)
+			return
+		}
+		obj.setScopePos(pos)
+	}
+	if id != nil {
+		check.recordDef(id, obj)
+	}
+}
+
+// objDecl type-checks the declaration of obj in its respective (file) context.
+// See check.typ for the details on def and path.
+func (check *Checker) objDecl(obj Object, def *Named, path []*TypeName) {
+	if obj.Type() != nil {
+		return // already checked - nothing to do
+	}
+
+	if trace {
+		check.trace(obj.Pos(), "-- declaring %s", obj.Name())
+		check.indent++
+		defer func() {
+			check.indent--
+			check.trace(obj.Pos(), "=> %s", obj)
+		}()
+	}
+
+	d := check.objMap[obj]
+	if d == nil {
+		check.dump("%s: %s should have been declared", obj.Pos(), obj.Name())
+		unreachable()
+	}
+
+	// save/restore current context and setup object context
+	defer func(ctxt context) {
+		check.context = ctxt
+	}(check.context)
+	check.context = context{
+		scope: d.file,
+	}
+
+	// Const and var declarations must not have initialization
+	// cycles. We track them by remembering the current declaration
+	// in check.decl. Initialization expressions depending on other
+	// consts, vars, or functions, add dependencies to the current
+	// check.decl.
+	switch obj := obj.(type) {
+	case *Const:
+		check.decl = d // new package-level const decl
+		check.constDecl(obj, d.typ, d.init)
+	case *Var:
+		check.decl = d // new package-level var decl
+		check.varDecl(obj, d.lhs, d.typ, d.init)
+	case *TypeName:
+		// invalid recursive types are detected via path
+		check.typeDecl(obj, d.typ, def, path)
+	case *Func:
+		// functions may be recursive - no need to track dependencies
+		check.funcDecl(obj, d)
+	default:
+		unreachable()
+	}
+}
+
+func (check *Checker) constDecl(obj *Const, typ, init ast.Expr) {
+	assert(obj.typ == nil)
+
+	if obj.visited {
+		obj.typ = Typ[Invalid]
+		return
+	}
+	obj.visited = true
+
+	// use the correct value of iota
+	assert(check.iota == nil)
+	check.iota = obj.val
+	defer func() { check.iota = nil }()
+
+	// provide valid constant value under all circumstances
+	obj.val = exact.MakeUnknown()
+
+	// determine type, if any
+	if typ != nil {
+		t := check.typ(typ)
+		if !isConstType(t) {
+			check.errorf(typ.Pos(), "invalid constant type %s", t)
+			obj.typ = Typ[Invalid]
+			return
+		}
+		obj.typ = t
+	}
+
+	// check initialization
+	var x operand
+	if init != nil {
+		check.expr(&x, init)
+	}
+	check.initConst(obj, &x)
+}
+
+func (check *Checker) varDecl(obj *Var, lhs []*Var, typ, init ast.Expr) {
+	assert(obj.typ == nil)
+
+	if obj.visited {
+		obj.typ = Typ[Invalid]
+		return
+	}
+	obj.visited = true
+
+	// var declarations cannot use iota
+	assert(check.iota == nil)
+
+	// determine type, if any
+	if typ != nil {
+		obj.typ = check.typ(typ)
+	}
+
+	// check initialization
+	if init == nil {
+		if typ == nil {
+			// error reported before by arityMatch
+			obj.typ = Typ[Invalid]
+		}
+		return
+	}
+
+	if lhs == nil || len(lhs) == 1 {
+		assert(lhs == nil || lhs[0] == obj)
+		var x operand
+		check.expr(&x, init)
+		check.initVar(obj, &x, false)
+		return
+	}
+
+	if debug {
+		// obj must be one of lhs
+		found := false
+		for _, lhs := range lhs {
+			if obj == lhs {
+				found = true
+				break
+			}
+		}
+		if !found {
+			panic("inconsistent lhs")
+		}
+	}
+	check.initVars(lhs, []ast.Expr{init}, token.NoPos)
+}
+
+// underlying returns the underlying type of typ; possibly by following
+// forward chains of named types. Such chains only exist while named types
+// are incomplete.
+func underlying(typ Type) Type {
+	for {
+		n, _ := typ.(*Named)
+		if n == nil {
+			break
+		}
+		typ = n.underlying
+	}
+	return typ
+}
+
+func (n *Named) setUnderlying(typ Type) {
+	if n != nil {
+		n.underlying = typ
+	}
+}
+
+func (check *Checker) typeDecl(obj *TypeName, typ ast.Expr, def *Named, path []*TypeName) {
+	assert(obj.typ == nil)
+
+	// type declarations cannot use iota
+	assert(check.iota == nil)
+
+	named := &Named{obj: obj}
+	def.setUnderlying(named)
+	obj.typ = named // make sure recursive type declarations terminate
+
+	// determine underlying type of named
+	check.typExpr(typ, named, append(path, obj))
+
+	// The underlying type of named may be itself a named type that is
+	// incomplete:
+	//
+	//	type (
+	//		A B
+	//		B *C
+	//		C A
+	//	)
+	//
+	// The type of C is the (named) type of A which is incomplete,
+	// and which has as its underlying type the named type B.
+	// Determine the (final, unnamed) underlying type by resolving
+	// any forward chain (they always end in an unnamed type).
+	named.underlying = underlying(named.underlying)
+
+	// check and add associated methods
+	// TODO(gri) It's easy to create pathological cases where the
+	// current approach is incorrect: In general we need to know
+	// and add all methods _before_ type-checking the type.
+	// See http://play.golang.org/p/WMpE0q2wK8
+	check.addMethodDecls(obj)
+}
+
+func (check *Checker) addMethodDecls(obj *TypeName) {
+	// get associated methods
+	methods := check.methods[obj.name]
+	if len(methods) == 0 {
+		return // no methods
+	}
+	delete(check.methods, obj.name)
+
+	// use an objset to check for name conflicts
+	var mset objset
+
+	// spec: "If the base type is a struct type, the non-blank method
+	// and field names must be distinct."
+	base := obj.typ.(*Named)
+	if t, _ := base.underlying.(*Struct); t != nil {
+		for _, fld := range t.fields {
+			if fld.name != "_" {
+				assert(mset.insert(fld) == nil)
+			}
+		}
+	}
+
+	// Checker.Files may be called multiple times; additional package files
+	// may add methods to already type-checked types. Add pre-existing methods
+	// so that we can detect redeclarations.
+	for _, m := range base.methods {
+		assert(m.name != "_")
+		assert(mset.insert(m) == nil)
+	}
+
+	// type-check methods
+	for _, m := range methods {
+		// spec: "For a base type, the non-blank names of methods bound
+		// to it must be unique."
+		if m.name != "_" {
+			if alt := mset.insert(m); alt != nil {
+				switch alt.(type) {
+				case *Var:
+					check.errorf(m.pos, "field and method with the same name %s", m.name)
+				case *Func:
+					check.errorf(m.pos, "method %s already declared for %s", m.name, base)
+				default:
+					unreachable()
+				}
+				check.reportAltDecl(alt)
+				continue
+			}
+		}
+		check.objDecl(m, nil, nil)
+		// methods with blank _ names cannot be found - don't keep them
+		if m.name != "_" {
+			base.methods = append(base.methods, m)
+		}
+	}
+}
+
+func (check *Checker) funcDecl(obj *Func, decl *declInfo) {
+	assert(obj.typ == nil)
+
+	// func declarations cannot use iota
+	assert(check.iota == nil)
+
+	sig := new(Signature)
+	obj.typ = sig // guard against cycles
+	fdecl := decl.fdecl
+	check.funcType(sig, fdecl.Recv, fdecl.Type)
+	if sig.recv == nil && obj.name == "init" && (sig.params.Len() > 0 || sig.results.Len() > 0) {
+		check.errorf(fdecl.Pos(), "func init must have no arguments and no return values")
+		// ok to continue
+	}
+
+	// function body must be type-checked after global declarations
+	// (functions implemented elsewhere have no body)
+	if !check.conf.IgnoreFuncBodies && fdecl.Body != nil {
+		check.later(obj.name, decl, sig, fdecl.Body)
+	}
+}
+
+func (check *Checker) declStmt(decl ast.Decl) {
+	pkg := check.pkg
+
+	switch d := decl.(type) {
+	case *ast.BadDecl:
+		// ignore
+
+	case *ast.GenDecl:
+		var last *ast.ValueSpec // last ValueSpec with type or init exprs seen
+		for iota, spec := range d.Specs {
+			switch s := spec.(type) {
+			case *ast.ValueSpec:
+				switch d.Tok {
+				case token.CONST:
+					// determine which init exprs to use
+					switch {
+					case s.Type != nil || len(s.Values) > 0:
+						last = s
+					case last == nil:
+						last = new(ast.ValueSpec) // make sure last exists
+					}
+
+					// declare all constants
+					lhs := make([]*Const, len(s.Names))
+					for i, name := range s.Names {
+						obj := NewConst(name.Pos(), pkg, name.Name, nil, exact.MakeInt64(int64(iota)))
+						lhs[i] = obj
+
+						var init ast.Expr
+						if i < len(last.Values) {
+							init = last.Values[i]
+						}
+
+						check.constDecl(obj, last.Type, init)
+					}
+
+					check.arityMatch(s, last)
+
+					// spec: "The scope of a constant or variable identifier declared
+					// inside a function begins at the end of the ConstSpec or VarSpec
+					// (ShortVarDecl for short variable declarations) and ends at the
+					// end of the innermost containing block."
+					scopePos := s.End()
+					for i, name := range s.Names {
+						check.declare(check.scope, name, lhs[i], scopePos)
+					}
+
+				case token.VAR:
+					lhs0 := make([]*Var, len(s.Names))
+					for i, name := range s.Names {
+						lhs0[i] = NewVar(name.Pos(), pkg, name.Name, nil)
+					}
+
+					// initialize all variables
+					for i, obj := range lhs0 {
+						var lhs []*Var
+						var init ast.Expr
+						switch len(s.Values) {
+						case len(s.Names):
+							// lhs and rhs match
+							init = s.Values[i]
+						case 1:
+							// rhs is expected to be a multi-valued expression
+							lhs = lhs0
+							init = s.Values[0]
+						default:
+							if i < len(s.Values) {
+								init = s.Values[i]
+							}
+						}
+						check.varDecl(obj, lhs, s.Type, init)
+						if len(s.Values) == 1 {
+							// If we have a single lhs variable we are done either way.
+							// If we have a single rhs expression, it must be a multi-
+							// valued expression, in which case handling the first lhs
+							// variable will cause all lhs variables to have a type
+							// assigned, and we are done as well.
+							if debug {
+								for _, obj := range lhs0 {
+									assert(obj.typ != nil)
+								}
+							}
+							break
+						}
+					}
+
+					check.arityMatch(s, nil)
+
+					// declare all variables
+					// (only at this point are the variable scopes (parents) set)
+					scopePos := s.End() // see constant declarations
+					for i, name := range s.Names {
+						// see constant declarations
+						check.declare(check.scope, name, lhs0[i], scopePos)
+					}
+
+				default:
+					check.invalidAST(s.Pos(), "invalid token %s", d.Tok)
+				}
+
+			case *ast.TypeSpec:
+				obj := NewTypeName(s.Name.Pos(), pkg, s.Name.Name, nil)
+				// spec: "The scope of a type identifier declared inside a function
+				// begins at the identifier in the TypeSpec and ends at the end of
+				// the innermost containing block."
+				scopePos := s.Name.Pos()
+				check.declare(check.scope, s.Name, obj, scopePos)
+				check.typeDecl(obj, s.Type, nil, nil)
+
+			default:
+				check.invalidAST(s.Pos(), "const, type, or var declaration expected")
+			}
+		}
+
+	default:
+		check.invalidAST(d.Pos(), "unknown ast.Decl node %T", d)
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/errors.go

@@ -0,0 +1,103 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements various error reporters.
+
+package types
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+	"strings"
+)
+
+func assert(p bool) {
+	if !p {
+		panic("assertion failed")
+	}
+}
+
+func unreachable() {
+	panic("unreachable")
+}
+
+func (check *Checker) qualifier(pkg *Package) string {
+	if pkg != check.pkg {
+		return pkg.path
+	}
+	return ""
+}
+
+func (check *Checker) sprintf(format string, args ...interface{}) string {
+	for i, arg := range args {
+		switch a := arg.(type) {
+		case nil:
+			arg = "<nil>"
+		case operand:
+			panic("internal error: should always pass *operand")
+		case *operand:
+			arg = operandString(a, check.qualifier)
+		case token.Pos:
+			arg = check.fset.Position(a).String()
+		case ast.Expr:
+			arg = ExprString(a)
+		case Object:
+			arg = ObjectString(a, check.qualifier)
+		case Type:
+			arg = TypeString(a, check.qualifier)
+		}
+		args[i] = arg
+	}
+	return fmt.Sprintf(format, args...)
+}
+
+func (check *Checker) trace(pos token.Pos, format string, args ...interface{}) {
+	fmt.Printf("%s:\t%s%s\n",
+		check.fset.Position(pos),
+		strings.Repeat(".  ", check.indent),
+		check.sprintf(format, args...),
+	)
+}
+
+// dump is only needed for debugging
+func (check *Checker) dump(format string, args ...interface{}) {
+	fmt.Println(check.sprintf(format, args...))
+}
+
+func (check *Checker) err(pos token.Pos, msg string, soft bool) {
+	err := Error{check.fset, pos, msg, soft}
+	if check.firstErr == nil {
+		check.firstErr = err
+	}
+	f := check.conf.Error
+	if f == nil {
+		panic(bailout{}) // report only first error
+	}
+	f(err)
+}
+
+func (check *Checker) error(pos token.Pos, msg string) {
+	check.err(pos, msg, false)
+}
+
+func (check *Checker) errorf(pos token.Pos, format string, args ...interface{}) {
+	check.err(pos, check.sprintf(format, args...), false)
+}
+
+func (check *Checker) softErrorf(pos token.Pos, format string, args ...interface{}) {
+	check.err(pos, check.sprintf(format, args...), true)
+}
+
+func (check *Checker) invalidAST(pos token.Pos, format string, args ...interface{}) {
+	check.errorf(pos, "invalid AST: "+format, args...)
+}
+
+func (check *Checker) invalidArg(pos token.Pos, format string, args ...interface{}) {
+	check.errorf(pos, "invalid argument: "+format, args...)
+}
+
+func (check *Checker) invalidOp(pos token.Pos, format string, args ...interface{}) {
+	check.errorf(pos, "invalid operation: "+format, args...)
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/eval.go

@@ -0,0 +1,87 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types
+
+import (
+	"fmt"
+	"go/parser"
+	"go/token"
+)
+
+// Eval returns the type and, if constant, the value for the
+// expression expr, evaluated at position pos of package pkg,
+// which must have been derived from type-checking an AST with
+// complete position information relative to the provided file
+// set.
+//
+// If the expression contains function literals, their bodies
+// are ignored (i.e., the bodies are not type-checked).
+//
+// If pkg == nil, the Universe scope is used and the provided
+// position pos is ignored. If pkg != nil, and pos is invalid,
+// the package scope is used. Otherwise, pos must belong to the
+// package.
+//
+// An error is returned if pos is not within the package or
+// if the node cannot be evaluated.
+//
+// Note: Eval should not be used instead of running Check to compute
+// types and values, but in addition to Check. Eval will re-evaluate
+// its argument each time, and it also does not know about the context
+// in which an expression is used (e.g., an assignment). Thus, top-
+// level untyped constants will return an untyped type rather then the
+// respective context-specific type.
+//
+func Eval(fset *token.FileSet, pkg *Package, pos token.Pos, expr string) (tv TypeAndValue, err error) {
+	// determine scope
+	var scope *Scope
+	if pkg == nil {
+		scope = Universe
+		pos = token.NoPos
+	} else if !pos.IsValid() {
+		scope = pkg.scope
+	} else {
+		// The package scope extent (position information) may be
+		// incorrect (files spread accross a wide range of fset
+		// positions) - ignore it and just consider its children
+		// (file scopes).
+		for _, fscope := range pkg.scope.children {
+			if scope = fscope.Innermost(pos); scope != nil {
+				break
+			}
+		}
+		if scope == nil || debug {
+			s := scope
+			for s != nil && s != pkg.scope {
+				s = s.parent
+			}
+			// s == nil || s == pkg.scope
+			if s == nil {
+				return TypeAndValue{}, fmt.Errorf("no position %s found in package %s", fset.Position(pos), pkg.name)
+			}
+		}
+	}
+
+	// parse expressions
+	// BUG(gri) In case of type-checking errors below, the type checker
+	//          doesn't have the correct file set for expr. The correct
+	//          solution requires a ParseExpr that uses the incoming
+	//          file set fset.
+	node, err := parser.ParseExpr(expr)
+	if err != nil {
+		return TypeAndValue{}, err
+	}
+
+	// initialize checker
+	check := NewChecker(nil, fset, pkg, nil)
+	check.scope = scope
+	check.pos = pos
+	defer check.handleBailout(&err)
+
+	// evaluate node
+	var x operand
+	check.rawExpr(&x, node, nil)
+	return TypeAndValue{x.mode, x.typ, x.val}, err
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/eval_test.go

@@ -0,0 +1,186 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file contains tests for Eval.
+
+package types_test
+
+import (
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"strings"
+	"testing"
+
+	_ "golang.org/x/tools/go/gcimporter"
+	. "golang.org/x/tools/go/types"
+)
+
+func testEval(t *testing.T, fset *token.FileSet, pkg *Package, pos token.Pos, expr string, typ Type, typStr, valStr string) {
+	gotTv, err := Eval(fset, pkg, pos, expr)
+	if err != nil {
+		t.Errorf("Eval(%q) failed: %s", expr, err)
+		return
+	}
+	if gotTv.Type == nil {
+		t.Errorf("Eval(%q) got nil type but no error", expr)
+		return
+	}
+
+	// compare types
+	if typ != nil {
+		// we have a type, check identity
+		if !Identical(gotTv.Type, typ) {
+			t.Errorf("Eval(%q) got type %s, want %s", expr, gotTv.Type, typ)
+			return
+		}
+	} else {
+		// we have a string, compare type string
+		gotStr := gotTv.Type.String()
+		if gotStr != typStr {
+			t.Errorf("Eval(%q) got type %s, want %s", expr, gotStr, typStr)
+			return
+		}
+	}
+
+	// compare values
+	gotStr := ""
+	if gotTv.Value != nil {
+		gotStr = gotTv.Value.String()
+	}
+	if gotStr != valStr {
+		t.Errorf("Eval(%q) got value %s, want %s", expr, gotStr, valStr)
+	}
+}
+
+func TestEvalBasic(t *testing.T) {
+	fset := token.NewFileSet()
+	for _, typ := range Typ[Bool : String+1] {
+		testEval(t, fset, nil, token.NoPos, typ.Name(), typ, "", "")
+	}
+}
+
+func TestEvalComposite(t *testing.T) {
+	fset := token.NewFileSet()
+	for _, test := range independentTestTypes {
+		testEval(t, fset, nil, token.NoPos, test.src, nil, test.str, "")
+	}
+}
+
+func TestEvalArith(t *testing.T) {
+	var tests = []string{
+		`true`,
+		`false == false`,
+		`12345678 + 87654321 == 99999999`,
+		`10 * 20 == 200`,
+		`(1<<1000)*2 >> 100 == 2<<900`,
+		`"foo" + "bar" == "foobar"`,
+		`"abc" <= "bcd"`,
+		`len([10]struct{}{}) == 2*5`,
+	}
+	fset := token.NewFileSet()
+	for _, test := range tests {
+		testEval(t, fset, nil, token.NoPos, test, Typ[UntypedBool], "", "true")
+	}
+}
+
+func TestEvalPos(t *testing.T) {
+	skipSpecialPlatforms(t)
+
+	// The contents of /*-style comments are of the form
+	//	expr => value, type
+	// where value may be the empty string.
+	// Each expr is evaluated at the position of the comment
+	// and the result is compared with the expected value
+	// and type.
+	var sources = []string{
+		`
+		package p
+		import "fmt"
+		import m "math"
+		const c = 3.0
+		type T []int
+		func f(a int, s string) float64 {
+			fmt.Println("calling f")
+			_ = m.Pi // use package math
+			const d int = c + 1
+			var x int
+			x = a + len(s)
+			return float64(x)
+			/* true => true, untyped bool */
+			/* fmt.Println => , func(a ...interface{}) (n int, err error) */
+			/* c => 3, untyped float */
+			/* T => , p.T */
+			/* a => , int */
+			/* s => , string */
+			/* d => 4, int */
+			/* x => , int */
+			/* d/c => 1, int */
+			/* c/2 => 3/2, untyped float */
+			/* m.Pi < m.E => false, untyped bool */
+		}
+		`,
+		`
+		package p
+		/* c => 3, untyped float */
+		type T1 /* T1 => , p.T1 */ struct {}
+		var v1 /* v1 => , int */ = 42
+		func /* f1 => , func(v1 float64) */ f1(v1 float64) {
+			/* f1 => , func(v1 float64) */
+			/* v1 => , float64 */
+			var c /* c => 3, untyped float */ = "foo" /* c => , string */
+			{
+				var c struct {
+					c /* c => , string */ int
+				}
+				/* c => , struct{c int} */
+				_ = c
+			}
+			_ = func(a, b, c int) /* c => , string */ {
+				/* c => , int */
+			}
+			_ = c
+			type FT /* FT => , p.FT */ interface{}
+		}
+		`,
+		`
+		package p
+		/* T => , p.T */
+		`,
+	}
+
+	fset := token.NewFileSet()
+	var files []*ast.File
+	for i, src := range sources {
+		file, err := parser.ParseFile(fset, "p", src, parser.ParseComments)
+		if err != nil {
+			t.Fatalf("could not parse file %d: %s", i, err)
+		}
+		files = append(files, file)
+	}
+
+	pkg, err := Check("p", fset, files)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	for _, file := range files {
+		for _, group := range file.Comments {
+			for _, comment := range group.List {
+				s := comment.Text
+				if len(s) >= 4 && s[:2] == "/*" && s[len(s)-2:] == "*/" {
+					str, typ := split(s[2:len(s)-2], ", ")
+					str, val := split(str, "=>")
+					testEval(t, fset, pkg, comment.Pos(), str, nil, typ, val)
+				}
+			}
+		}
+	}
+}
+
+// split splits string s at the first occurrence of s.
+func split(s, sep string) (string, string) {
+	i := strings.Index(s, sep)
+	return strings.TrimSpace(s[:i]), strings.TrimSpace(s[i+len(sep):])
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/exprstring.go

@@ -0,0 +1,220 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements printing of expressions.
+
+package types
+
+import (
+	"bytes"
+	"go/ast"
+)
+
+// ExprString returns the (possibly simplified) string representation for x.
+func ExprString(x ast.Expr) string {
+	var buf bytes.Buffer
+	WriteExpr(&buf, x)
+	return buf.String()
+}
+
+// WriteExpr writes the (possibly simplified) string representation for x to buf.
+func WriteExpr(buf *bytes.Buffer, x ast.Expr) {
+	// The AST preserves source-level parentheses so there is
+	// no need to introduce them here to correct for different
+	// operator precedences. (This assumes that the AST was
+	// generated by a Go parser.)
+
+	switch x := x.(type) {
+	default:
+		buf.WriteString("(bad expr)") // nil, ast.BadExpr, ast.KeyValueExpr
+
+	case *ast.Ident:
+		buf.WriteString(x.Name)
+
+	case *ast.Ellipsis:
+		buf.WriteString("...")
+		if x.Elt != nil {
+			WriteExpr(buf, x.Elt)
+		}
+
+	case *ast.BasicLit:
+		buf.WriteString(x.Value)
+
+	case *ast.FuncLit:
+		buf.WriteByte('(')
+		WriteExpr(buf, x.Type)
+		buf.WriteString(" literal)") // simplified
+
+	case *ast.CompositeLit:
+		buf.WriteByte('(')
+		WriteExpr(buf, x.Type)
+		buf.WriteString(" literal)") // simplified
+
+	case *ast.ParenExpr:
+		buf.WriteByte('(')
+		WriteExpr(buf, x.X)
+		buf.WriteByte(')')
+
+	case *ast.SelectorExpr:
+		WriteExpr(buf, x.X)
+		buf.WriteByte('.')
+		buf.WriteString(x.Sel.Name)
+
+	case *ast.IndexExpr:
+		WriteExpr(buf, x.X)
+		buf.WriteByte('[')
+		WriteExpr(buf, x.Index)
+		buf.WriteByte(']')
+
+	case *ast.SliceExpr:
+		WriteExpr(buf, x.X)
+		buf.WriteByte('[')
+		if x.Low != nil {
+			WriteExpr(buf, x.Low)
+		}
+		buf.WriteByte(':')
+		if x.High != nil {
+			WriteExpr(buf, x.High)
+		}
+		if x.Slice3 {
+			buf.WriteByte(':')
+			if x.Max != nil {
+				WriteExpr(buf, x.Max)
+			}
+		}
+		buf.WriteByte(']')
+
+	case *ast.TypeAssertExpr:
+		WriteExpr(buf, x.X)
+		buf.WriteString(".(")
+		WriteExpr(buf, x.Type)
+		buf.WriteByte(')')
+
+	case *ast.CallExpr:
+		WriteExpr(buf, x.Fun)
+		buf.WriteByte('(')
+		for i, arg := range x.Args {
+			if i > 0 {
+				buf.WriteString(", ")
+			}
+			WriteExpr(buf, arg)
+		}
+		if x.Ellipsis.IsValid() {
+			buf.WriteString("...")
+		}
+		buf.WriteByte(')')
+
+	case *ast.StarExpr:
+		buf.WriteByte('*')
+		WriteExpr(buf, x.X)
+
+	case *ast.UnaryExpr:
+		buf.WriteString(x.Op.String())
+		WriteExpr(buf, x.X)
+
+	case *ast.BinaryExpr:
+		WriteExpr(buf, x.X)
+		buf.WriteByte(' ')
+		buf.WriteString(x.Op.String())
+		buf.WriteByte(' ')
+		WriteExpr(buf, x.Y)
+
+	case *ast.ArrayType:
+		buf.WriteByte('[')
+		if x.Len != nil {
+			WriteExpr(buf, x.Len)
+		}
+		buf.WriteByte(']')
+		WriteExpr(buf, x.Elt)
+
+	case *ast.StructType:
+		buf.WriteString("struct{")
+		writeFieldList(buf, x.Fields, "; ", false)
+		buf.WriteByte('}')
+
+	case *ast.FuncType:
+		buf.WriteString("func")
+		writeSigExpr(buf, x)
+
+	case *ast.InterfaceType:
+		buf.WriteString("interface{")
+		writeFieldList(buf, x.Methods, "; ", true)
+		buf.WriteByte('}')
+
+	case *ast.MapType:
+		buf.WriteString("map[")
+		WriteExpr(buf, x.Key)
+		buf.WriteByte(']')
+		WriteExpr(buf, x.Value)
+
+	case *ast.ChanType:
+		var s string
+		switch x.Dir {
+		case ast.SEND:
+			s = "chan<- "
+		case ast.RECV:
+			s = "<-chan "
+		default:
+			s = "chan "
+		}
+		buf.WriteString(s)
+		WriteExpr(buf, x.Value)
+	}
+}
+
+func writeSigExpr(buf *bytes.Buffer, sig *ast.FuncType) {
+	buf.WriteByte('(')
+	writeFieldList(buf, sig.Params, ", ", false)
+	buf.WriteByte(')')
+
+	res := sig.Results
+	n := res.NumFields()
+	if n == 0 {
+		// no result
+		return
+	}
+
+	buf.WriteByte(' ')
+	if n == 1 && len(res.List[0].Names) == 0 {
+		// single unnamed result
+		WriteExpr(buf, res.List[0].Type)
+		return
+	}
+
+	// multiple or named result(s)
+	buf.WriteByte('(')
+	writeFieldList(buf, res, ", ", false)
+	buf.WriteByte(')')
+}
+
+func writeFieldList(buf *bytes.Buffer, fields *ast.FieldList, sep string, iface bool) {
+	for i, f := range fields.List {
+		if i > 0 {
+			buf.WriteString(sep)
+		}
+
+		// field list names
+		for i, name := range f.Names {
+			if i > 0 {
+				buf.WriteString(", ")
+			}
+			buf.WriteString(name.Name)
+		}
+
+		// types of interface methods consist of signatures only
+		if sig, _ := f.Type.(*ast.FuncType); sig != nil && iface {
+			writeSigExpr(buf, sig)
+			continue
+		}
+
+		// named fields are separated with a blank from the field type
+		if len(f.Names) > 0 {
+			buf.WriteByte(' ')
+		}
+
+		WriteExpr(buf, f.Type)
+
+		// ignore tag
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/exprstring_test.go

@@ -0,0 +1,94 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types_test
+
+import (
+	"go/parser"
+	"testing"
+
+	. "golang.org/x/tools/go/types"
+)
+
+var testExprs = []testEntry{
+	// basic type literals
+	dup("x"),
+	dup("true"),
+	dup("42"),
+	dup("3.1415"),
+	dup("2.71828i"),
+	dup(`'a'`),
+	dup(`"foo"`),
+	dup("`bar`"),
+
+	// func and composite literals
+	{"func(){}", "(func() literal)"},
+	{"func(x int) complex128 {}", "(func(x int) complex128 literal)"},
+	{"[]int{1, 2, 3}", "([]int literal)"},
+
+	// non-type expressions
+	dup("(x)"),
+	dup("x.f"),
+	dup("a[i]"),
+
+	dup("s[:]"),
+	dup("s[i:]"),
+	dup("s[:j]"),
+	dup("s[i:j]"),
+	dup("s[:j:k]"),
+	dup("s[i:j:k]"),
+
+	dup("x.(T)"),
+
+	dup("x.([10]int)"),
+	dup("x.([...]int)"),
+
+	dup("x.(struct{})"),
+	dup("x.(struct{x int; y, z float32; E})"),
+
+	dup("x.(func())"),
+	dup("x.(func(x int))"),
+	dup("x.(func() int)"),
+	dup("x.(func(x, y int, z float32) (r int))"),
+	dup("x.(func(a, b, c int))"),
+	dup("x.(func(x ...T))"),
+
+	dup("x.(interface{})"),
+	dup("x.(interface{m(); n(x int); E})"),
+	dup("x.(interface{m(); n(x int) T; E; F})"),
+
+	dup("x.(map[K]V)"),
+
+	dup("x.(chan E)"),
+	dup("x.(<-chan E)"),
+	dup("x.(chan<- chan int)"),
+	dup("x.(chan<- <-chan int)"),
+	dup("x.(<-chan chan int)"),
+	dup("x.(chan (<-chan int))"),
+
+	dup("f()"),
+	dup("f(x)"),
+	dup("int(x)"),
+	dup("f(x, x + y)"),
+	dup("f(s...)"),
+	dup("f(a, s...)"),
+
+	dup("*x"),
+	dup("&x"),
+	dup("x + y"),
+	dup("x + y << (2 * s)"),
+}
+
+func TestExprString(t *testing.T) {
+	for _, test := range testExprs {
+		x, err := parser.ParseExpr(test.src)
+		if err != nil {
+			t.Errorf("%s: %s", test.src, err)
+			continue
+		}
+		if got := ExprString(x); got != test.str {
+			t.Errorf("%s: got %s, want %s", test.src, got, test.str)
+		}
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/go11.go

@@ -0,0 +1,17 @@
+// Copyright 2013 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !go1.2
+
+package types
+
+import "go/ast"
+
+func slice3(x *ast.SliceExpr) bool {
+	return false
+}
+
+func sliceMax(x *ast.SliceExpr) ast.Expr {
+	return nil
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/go12.go

@@ -0,0 +1,17 @@
+// Copyright 2013 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.2
+
+package types
+
+import "go/ast"
+
+func slice3(x *ast.SliceExpr) bool {
+	return x.Slice3
+}
+
+func sliceMax(x *ast.SliceExpr) ast.Expr {
+	return x.Max
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/hilbert_test.go

@@ -0,0 +1,232 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types_test
+
+import (
+	"bytes"
+	"flag"
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"io/ioutil"
+	"testing"
+
+	. "golang.org/x/tools/go/types"
+)
+
+var (
+	H   = flag.Int("H", 5, "Hilbert matrix size")
+	out = flag.String("out", "", "write generated program to out")
+)
+
+func TestHilbert(t *testing.T) {
+	// generate source
+	src := program(*H, *out)
+	if *out != "" {
+		ioutil.WriteFile(*out, src, 0666)
+		return
+	}
+
+	// parse source
+	fset := token.NewFileSet()
+	f, err := parser.ParseFile(fset, "hilbert.go", src, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// type-check file
+	DefPredeclaredTestFuncs() // define assert built-in
+	_, err = Check(f.Name.Name, fset, []*ast.File{f})
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+func program(n int, out string) []byte {
+	var g gen
+
+	g.p(`// WARNING: GENERATED FILE - DO NOT MODIFY MANUALLY!
+// (To generate, in go/types directory: go test -run=Hilbert -H=%d -out=%q)
+
+// This program tests arbitrary precision constant arithmetic
+// by generating the constant elements of a Hilbert matrix H,
+// its inverse I, and the product P = H*I. The product should
+// be the identity matrix.
+package main
+
+func main() {
+	if !ok {
+		printProduct()
+		return
+	}
+	println("PASS")
+}
+
+`, n, out)
+	g.hilbert(n)
+	g.inverse(n)
+	g.product(n)
+	g.verify(n)
+	g.printProduct(n)
+	g.binomials(2*n - 1)
+	g.factorials(2*n - 1)
+
+	return g.Bytes()
+}
+
+type gen struct {
+	bytes.Buffer
+}
+
+func (g *gen) p(format string, args ...interface{}) {
+	fmt.Fprintf(&g.Buffer, format, args...)
+}
+
+func (g *gen) hilbert(n int) {
+	g.p(`// Hilbert matrix, n = %d
+const (
+`, n)
+	for i := 0; i < n; i++ {
+		g.p("\t")
+		for j := 0; j < n; j++ {
+			if j > 0 {
+				g.p(", ")
+			}
+			g.p("h%d_%d", i, j)
+		}
+		if i == 0 {
+			g.p(" = ")
+			for j := 0; j < n; j++ {
+				if j > 0 {
+					g.p(", ")
+				}
+				g.p("1.0/(iota + %d)", j+1)
+			}
+		}
+		g.p("\n")
+	}
+	g.p(")\n\n")
+}
+
+func (g *gen) inverse(n int) {
+	g.p(`// Inverse Hilbert matrix
+const (
+`)
+	for i := 0; i < n; i++ {
+		for j := 0; j < n; j++ {
+			s := "+"
+			if (i+j)&1 != 0 {
+				s = "-"
+			}
+			g.p("\ti%d_%d = %s%d * b%d_%d * b%d_%d * b%d_%d * b%d_%d\n",
+				i, j, s, i+j+1, n+i, n-j-1, n+j, n-i-1, i+j, i, i+j, i)
+		}
+		g.p("\n")
+	}
+	g.p(")\n\n")
+}
+
+func (g *gen) product(n int) {
+	g.p(`// Product matrix
+const (
+`)
+	for i := 0; i < n; i++ {
+		for j := 0; j < n; j++ {
+			g.p("\tp%d_%d = ", i, j)
+			for k := 0; k < n; k++ {
+				if k > 0 {
+					g.p(" + ")
+				}
+				g.p("h%d_%d*i%d_%d", i, k, k, j)
+			}
+			g.p("\n")
+		}
+		g.p("\n")
+	}
+	g.p(")\n\n")
+}
+
+func (g *gen) verify(n int) {
+	g.p(`// Verify that product is the identity matrix
+const ok =
+`)
+	for i := 0; i < n; i++ {
+		for j := 0; j < n; j++ {
+			if j == 0 {
+				g.p("\t")
+			} else {
+				g.p(" && ")
+			}
+			v := 0
+			if i == j {
+				v = 1
+			}
+			g.p("p%d_%d == %d", i, j, v)
+		}
+		g.p(" &&\n")
+	}
+	g.p("\ttrue\n\n")
+
+	// verify ok at type-check time
+	if *out == "" {
+		g.p("const _ = assert(ok)\n\n")
+	}
+}
+
+func (g *gen) printProduct(n int) {
+	g.p("func printProduct() {\n")
+	for i := 0; i < n; i++ {
+		g.p("\tprintln(")
+		for j := 0; j < n; j++ {
+			if j > 0 {
+				g.p(", ")
+			}
+			g.p("p%d_%d", i, j)
+		}
+		g.p(")\n")
+	}
+	g.p("}\n\n")
+}
+
+func (g *gen) mulRange(a, b int) {
+	if a > b {
+		g.p("1")
+		return
+	}
+	for i := a; i <= b; i++ {
+		if i > a {
+			g.p("*")
+		}
+		g.p("%d", i)
+	}
+}
+
+func (g *gen) binomials(n int) {
+	g.p(`// Binomials
+const (
+`)
+	for j := 0; j <= n; j++ {
+		if j > 0 {
+			g.p("\n")
+		}
+		for k := 0; k <= j; k++ {
+			g.p("\tb%d_%d = f%d / (f%d*f%d)\n", j, k, j, k, j-k)
+		}
+	}
+	g.p(")\n\n")
+}
+
+func (g *gen) factorials(n int) {
+	g.p(`// Factorials
+const (
+	f0 = 1
+	f1 = 1
+`)
+	for i := 2; i <= n; i++ {
+		g.p("\tf%d = f%d * %d\n", i, i-1, i)
+	}
+	g.p(")\n\n")
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/initorder.go

@@ -0,0 +1,222 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types
+
+import (
+	"container/heap"
+	"fmt"
+)
+
+// initOrder computes the Info.InitOrder for package variables.
+func (check *Checker) initOrder() {
+	// An InitOrder may already have been computed if a package is
+	// built from several calls to (*Checker).Files.  Clear it.
+	check.Info.InitOrder = check.Info.InitOrder[:0]
+
+	// compute the object dependency graph and
+	// initialize a priority queue with the list
+	// of graph nodes
+	pq := nodeQueue(dependencyGraph(check.objMap))
+	heap.Init(&pq)
+
+	const debug = false
+	if debug {
+		fmt.Printf("package %s: object dependency graph\n", check.pkg.Name())
+		for _, n := range pq {
+			for _, o := range n.out {
+				fmt.Printf("\t%s -> %s\n", n.obj.Name(), o.obj.Name())
+			}
+		}
+		fmt.Println()
+		fmt.Printf("package %s: initialization order\n", check.pkg.Name())
+	}
+
+	// determine initialization order by removing the highest priority node
+	// (the one with the fewest dependencies) and its edges from the graph,
+	// repeatedly, until there are no nodes left.
+	// In a valid Go program, those nodes always have zero dependencies (after
+	// removing all incoming dependencies), otherwise there are initialization
+	// cycles.
+	mark := 0
+	emitted := make(map[*declInfo]bool)
+	for len(pq) > 0 {
+		// get the next node
+		n := heap.Pop(&pq).(*objNode)
+
+		// if n still depends on other nodes, we have a cycle
+		if n.in > 0 {
+			mark++ // mark nodes using a different value each time
+			cycle := findPath(n, n, mark)
+			if i := valIndex(cycle); i >= 0 {
+				check.reportCycle(cycle, i)
+			}
+			// ok to continue, but the variable initialization order
+			// will be incorrect at this point since it assumes no
+			// cycle errors
+		}
+
+		// reduce dependency count of all dependent nodes
+		// and update priority queue
+		for _, out := range n.out {
+			out.in--
+			heap.Fix(&pq, out.index)
+		}
+
+		// record the init order for variables with initializers only
+		v, _ := n.obj.(*Var)
+		info := check.objMap[v]
+		if v == nil || !info.hasInitializer() {
+			continue
+		}
+
+		// n:1 variable declarations such as: a, b = f()
+		// introduce a node for each lhs variable (here: a, b);
+		// but they all have the same initializer - emit only
+		// one, for the first variable seen
+		if emitted[info] {
+			continue // initializer already emitted, if any
+		}
+		emitted[info] = true
+
+		infoLhs := info.lhs // possibly nil (see declInfo.lhs field comment)
+		if infoLhs == nil {
+			infoLhs = []*Var{v}
+		}
+		init := &Initializer{infoLhs, info.init}
+		check.Info.InitOrder = append(check.Info.InitOrder, init)
+
+		if debug {
+			fmt.Printf("\t%s\n", init)
+		}
+	}
+
+	if debug {
+		fmt.Println()
+	}
+}
+
+// findPath returns the (reversed) list of nodes z, ... c, b, a,
+// such that there is a path (list of edges) from a to z.
+// If there is no such path, the result is nil.
+// Nodes marked with the value mark are considered "visited";
+// unvisited nodes are marked during the graph search.
+func findPath(a, z *objNode, mark int) []*objNode {
+	if a.mark == mark {
+		return nil // node already seen
+	}
+	a.mark = mark
+
+	for _, n := range a.out {
+		if n == z {
+			return []*objNode{z}
+		}
+		if P := findPath(n, z, mark); P != nil {
+			return append(P, n)
+		}
+	}
+
+	return nil
+}
+
+// valIndex returns the index of the first constant or variable in a,
+// if any; or a value < 0.
+func valIndex(a []*objNode) int {
+	for i, n := range a {
+		switch n.obj.(type) {
+		case *Const, *Var:
+			return i
+		}
+	}
+	return -1
+}
+
+// reportCycle reports an error for the cycle starting at i.
+func (check *Checker) reportCycle(cycle []*objNode, i int) {
+	obj := cycle[i].obj
+	check.errorf(obj.Pos(), "initialization cycle for %s", obj.Name())
+	// print cycle
+	for _ = range cycle {
+		check.errorf(obj.Pos(), "\t%s refers to", obj.Name()) // secondary error, \t indented
+		i++
+		if i >= len(cycle) {
+			i = 0
+		}
+		obj = cycle[i].obj
+	}
+	check.errorf(obj.Pos(), "\t%s", obj.Name())
+}
+
+// An objNode represents a node in the object dependency graph.
+// Each node b in a.out represents an edge a->b indicating that
+// b depends on a.
+// Nodes may be marked for cycle detection. A node n is marked
+// if n.mark corresponds to the current mark value.
+type objNode struct {
+	obj   Object     // object represented by this node
+	in    int        // number of nodes this node depends on
+	out   []*objNode // list of nodes that depend on this node
+	index int        // node index in list of nodes
+	mark  int        // for cycle detection
+}
+
+// dependencyGraph computes the transposed object dependency graph
+// from the given objMap. The transposed graph is returned as a list
+// of nodes; an edge d->n indicates that node n depends on node d.
+func dependencyGraph(objMap map[Object]*declInfo) []*objNode {
+	// M maps each object to its corresponding node
+	M := make(map[Object]*objNode, len(objMap))
+	for obj := range objMap {
+		M[obj] = &objNode{obj: obj}
+	}
+
+	// G is the graph of nodes n
+	G := make([]*objNode, len(M))
+	i := 0
+	for obj, n := range M {
+		deps := objMap[obj].deps
+		n.in = len(deps)
+		for d := range deps {
+			d := M[d]                // node n depends on node d
+			d.out = append(d.out, n) // add edge d->n
+		}
+
+		G[i] = n
+		n.index = i
+		i++
+	}
+
+	return G
+}
+
+// nodeQueue implements the container/heap interface;
+// a nodeQueue may be used as a priority queue.
+type nodeQueue []*objNode
+
+func (a nodeQueue) Len() int { return len(a) }
+
+func (a nodeQueue) Swap(i, j int) {
+	x, y := a[i], a[j]
+	a[i], a[j] = y, x
+	x.index, y.index = j, i
+}
+
+func (a nodeQueue) Less(i, j int) bool {
+	x, y := a[i], a[j]
+	// nodes are prioritized by number of incoming dependencies (1st key)
+	// and source order (2nd key)
+	return x.in < y.in || x.in == y.in && x.obj.order() < y.obj.order()
+}
+
+func (a *nodeQueue) Push(x interface{}) {
+	panic("unreachable")
+}
+
+func (a *nodeQueue) Pop() interface{} {
+	n := len(*a)
+	x := (*a)[n-1]
+	x.index = -1 // for safety
+	*a = (*a)[:n-1]
+	return x
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/issues_test.go

@@ -0,0 +1,205 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements tests for various issues.
+
+package types_test
+
+import (
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"sort"
+	"strings"
+	"testing"
+
+	_ "golang.org/x/tools/go/gcimporter"
+	. "golang.org/x/tools/go/types"
+)
+
+func TestIssue5770(t *testing.T) {
+	src := `package p; type S struct{T}`
+	f, err := parser.ParseFile(fset, "", src, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, err = Check(f.Name.Name, fset, []*ast.File{f}) // do not crash
+	want := "undeclared name: T"
+	if err == nil || !strings.Contains(err.Error(), want) {
+		t.Errorf("got: %v; want: %s", err, want)
+	}
+}
+
+func TestIssue5849(t *testing.T) {
+	src := `
+package p
+var (
+	s uint
+	_ = uint8(8)
+	_ = uint16(16) << s
+	_ = uint32(32 << s)
+	_ = uint64(64 << s + s)
+	_ = (interface{})("foo")
+	_ = (interface{})(nil)
+)`
+	f, err := parser.ParseFile(fset, "", src, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var conf Config
+	types := make(map[ast.Expr]TypeAndValue)
+	_, err = conf.Check(f.Name.Name, fset, []*ast.File{f}, &Info{Types: types})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	for x, tv := range types {
+		var want Type
+		switch x := x.(type) {
+		case *ast.BasicLit:
+			switch x.Value {
+			case `8`:
+				want = Typ[Uint8]
+			case `16`:
+				want = Typ[Uint16]
+			case `32`:
+				want = Typ[Uint32]
+			case `64`:
+				want = Typ[Uint] // because of "+ s", s is of type uint
+			case `"foo"`:
+				want = Typ[String]
+			}
+		case *ast.Ident:
+			if x.Name == "nil" {
+				want = Typ[UntypedNil]
+			}
+		}
+		if want != nil && !Identical(tv.Type, want) {
+			t.Errorf("got %s; want %s", tv.Type, want)
+		}
+	}
+}
+
+func TestIssue6413(t *testing.T) {
+	src := `
+package p
+func f() int {
+	defer f()
+	go f()
+	return 0
+}
+`
+	f, err := parser.ParseFile(fset, "", src, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var conf Config
+	types := make(map[ast.Expr]TypeAndValue)
+	_, err = conf.Check(f.Name.Name, fset, []*ast.File{f}, &Info{Types: types})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	want := Typ[Int]
+	n := 0
+	for x, tv := range types {
+		if _, ok := x.(*ast.CallExpr); ok {
+			if tv.Type != want {
+				t.Errorf("%s: got %s; want %s", fset.Position(x.Pos()), tv.Type, want)
+			}
+			n++
+		}
+	}
+
+	if n != 2 {
+		t.Errorf("got %d CallExprs; want 2", n)
+	}
+}
+
+func TestIssue7245(t *testing.T) {
+	src := `
+package p
+func (T) m() (res bool) { return }
+type T struct{} // receiver type after method declaration
+`
+	f, err := parser.ParseFile(fset, "", src, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var conf Config
+	defs := make(map[*ast.Ident]Object)
+	_, err = conf.Check(f.Name.Name, fset, []*ast.File{f}, &Info{Defs: defs})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	m := f.Decls[0].(*ast.FuncDecl)
+	res1 := defs[m.Name].(*Func).Type().(*Signature).Results().At(0)
+	res2 := defs[m.Type.Results.List[0].Names[0]].(*Var)
+
+	if res1 != res2 {
+		t.Errorf("got %s (%p) != %s (%p)", res1, res2, res1, res2)
+	}
+}
+
+// This tests that uses of existing vars on the LHS of an assignment
+// are Uses, not Defs; and also that the (illegal) use of a non-var on
+// the LHS of an assignment is a Use nonetheless.
+func TestIssue7827(t *testing.T) {
+	const src = `
+package p
+func _() {
+	const w = 1        // defs w
+        x, y := 2, 3       // defs x, y
+        w, x, z := 4, 5, 6 // uses w, x, defs z; error: cannot assign to w
+        _, _, _ = x, y, z  // uses x, y, z
+}
+`
+	const want = `L3 defs func p._()
+L4 defs const w untyped int
+L5 defs var x int
+L5 defs var y int
+L6 defs var z int
+L6 uses const w untyped int
+L6 uses var x int
+L7 uses var x int
+L7 uses var y int
+L7 uses var z int`
+
+	f, err := parser.ParseFile(fset, "", src, 0)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// don't abort at the first error
+	conf := Config{Error: func(err error) { t.Log(err) }}
+	defs := make(map[*ast.Ident]Object)
+	uses := make(map[*ast.Ident]Object)
+	_, err = conf.Check(f.Name.Name, fset, []*ast.File{f}, &Info{Defs: defs, Uses: uses})
+	if s := fmt.Sprint(err); !strings.HasSuffix(s, "cannot assign to w") {
+		t.Errorf("Check: unexpected error: %s", s)
+	}
+
+	var facts []string
+	for id, obj := range defs {
+		if obj != nil {
+			fact := fmt.Sprintf("L%d defs %s", fset.Position(id.Pos()).Line, obj)
+			facts = append(facts, fact)
+		}
+	}
+	for id, obj := range uses {
+		fact := fmt.Sprintf("L%d uses %s", fset.Position(id.Pos()).Line, obj)
+		facts = append(facts, fact)
+	}
+	sort.Strings(facts)
+
+	got := strings.Join(facts, "\n")
+	if got != want {
+		t.Errorf("Unexpected defs/uses\ngot:\n%s\nwant:\n%s", got, want)
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/labels.go

@@ -0,0 +1,268 @@
+// Copyright 2013 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types
+
+import (
+	"go/ast"
+	"go/token"
+)
+
+// labels checks correct label use in body.
+func (check *Checker) labels(body *ast.BlockStmt) {
+	// set of all labels in this body
+	all := NewScope(nil, body.Pos(), body.End(), "label")
+
+	fwdJumps := check.blockBranches(all, nil, nil, body.List)
+
+	// If there are any forward jumps left, no label was found for
+	// the corresponding goto statements. Either those labels were
+	// never defined, or they are inside blocks and not reachable
+	// for the respective gotos.
+	for _, jmp := range fwdJumps {
+		var msg string
+		name := jmp.Label.Name
+		if alt := all.Lookup(name); alt != nil {
+			msg = "goto %s jumps into block"
+			alt.(*Label).used = true // avoid another error
+		} else {
+			msg = "label %s not declared"
+		}
+		check.errorf(jmp.Label.Pos(), msg, name)
+	}
+
+	// spec: "It is illegal to define a label that is never used."
+	for _, obj := range all.elems {
+		if lbl := obj.(*Label); !lbl.used {
+			check.softErrorf(lbl.pos, "label %s declared but not used", lbl.name)
+		}
+	}
+}
+
+// A block tracks label declarations in a block and its enclosing blocks.
+type block struct {
+	parent *block                      // enclosing block
+	lstmt  *ast.LabeledStmt            // labeled statement to which this block belongs, or nil
+	labels map[string]*ast.LabeledStmt // allocated lazily
+}
+
+// insert records a new label declaration for the current block.
+// The label must not have been declared before in any block.
+func (b *block) insert(s *ast.LabeledStmt) {
+	name := s.Label.Name
+	if debug {
+		assert(b.gotoTarget(name) == nil)
+	}
+	labels := b.labels
+	if labels == nil {
+		labels = make(map[string]*ast.LabeledStmt)
+		b.labels = labels
+	}
+	labels[name] = s
+}
+
+// gotoTarget returns the labeled statement in the current
+// or an enclosing block with the given label name, or nil.
+func (b *block) gotoTarget(name string) *ast.LabeledStmt {
+	for s := b; s != nil; s = s.parent {
+		if t := s.labels[name]; t != nil {
+			return t
+		}
+	}
+	return nil
+}
+
+// enclosingTarget returns the innermost enclosing labeled
+// statement with the given label name, or nil.
+func (b *block) enclosingTarget(name string) *ast.LabeledStmt {
+	for s := b; s != nil; s = s.parent {
+		if t := s.lstmt; t != nil && t.Label.Name == name {
+			return t
+		}
+	}
+	return nil
+}
+
+// blockBranches processes a block's statement list and returns the set of outgoing forward jumps.
+// all is the scope of all declared labels, parent the set of labels declared in the immediately
+// enclosing block, and lstmt is the labeled statement this block is associated with (or nil).
+func (check *Checker) blockBranches(all *Scope, parent *block, lstmt *ast.LabeledStmt, list []ast.Stmt) []*ast.BranchStmt {
+	b := &block{parent: parent, lstmt: lstmt}
+
+	var (
+		varDeclPos         token.Pos
+		fwdJumps, badJumps []*ast.BranchStmt
+	)
+
+	// All forward jumps jumping over a variable declaration are possibly
+	// invalid (they may still jump out of the block and be ok).
+	// recordVarDecl records them for the given position.
+	recordVarDecl := func(pos token.Pos) {
+		varDeclPos = pos
+		badJumps = append(badJumps[:0], fwdJumps...) // copy fwdJumps to badJumps
+	}
+
+	jumpsOverVarDecl := func(jmp *ast.BranchStmt) bool {
+		if varDeclPos.IsValid() {
+			for _, bad := range badJumps {
+				if jmp == bad {
+					return true
+				}
+			}
+		}
+		return false
+	}
+
+	blockBranches := func(lstmt *ast.LabeledStmt, list []ast.Stmt) {
+		// Unresolved forward jumps inside the nested block
+		// become forward jumps in the current block.
+		fwdJumps = append(fwdJumps, check.blockBranches(all, b, lstmt, list)...)
+	}
+
+	var stmtBranches func(ast.Stmt)
+	stmtBranches = func(s ast.Stmt) {
+		switch s := s.(type) {
+		case *ast.DeclStmt:
+			if d, _ := s.Decl.(*ast.GenDecl); d != nil && d.Tok == token.VAR {
+				recordVarDecl(d.Pos())
+			}
+
+		case *ast.LabeledStmt:
+			// declare non-blank label
+			if name := s.Label.Name; name != "_" {
+				lbl := NewLabel(s.Label.Pos(), check.pkg, name)
+				if alt := all.Insert(lbl); alt != nil {
+					check.softErrorf(lbl.pos, "label %s already declared", name)
+					check.reportAltDecl(alt)
+					// ok to continue
+				} else {
+					b.insert(s)
+					check.recordDef(s.Label, lbl)
+				}
+				// resolve matching forward jumps and remove them from fwdJumps
+				i := 0
+				for _, jmp := range fwdJumps {
+					if jmp.Label.Name == name {
+						// match
+						lbl.used = true
+						check.recordUse(jmp.Label, lbl)
+						if jumpsOverVarDecl(jmp) {
+							check.softErrorf(
+								jmp.Label.Pos(),
+								"goto %s jumps over variable declaration at line %d",
+								name,
+								check.fset.Position(varDeclPos).Line,
+							)
+							// ok to continue
+						}
+					} else {
+						// no match - record new forward jump
+						fwdJumps[i] = jmp
+						i++
+					}
+				}
+				fwdJumps = fwdJumps[:i]
+				lstmt = s
+			}
+			stmtBranches(s.Stmt)
+
+		case *ast.BranchStmt:
+			if s.Label == nil {
+				return // checked in 1st pass (check.stmt)
+			}
+
+			// determine and validate target
+			name := s.Label.Name
+			switch s.Tok {
+			case token.BREAK:
+				// spec: "If there is a label, it must be that of an enclosing
+				// "for", "switch", or "select" statement, and that is the one
+				// whose execution terminates."
+				valid := false
+				if t := b.enclosingTarget(name); t != nil {
+					switch t.Stmt.(type) {
+					case *ast.SwitchStmt, *ast.TypeSwitchStmt, *ast.SelectStmt, *ast.ForStmt, *ast.RangeStmt:
+						valid = true
+					}
+				}
+				if !valid {
+					check.errorf(s.Label.Pos(), "invalid break label %s", name)
+					return
+				}
+
+			case token.CONTINUE:
+				// spec: "If there is a label, it must be that of an enclosing
+				// "for" statement, and that is the one whose execution advances."
+				valid := false
+				if t := b.enclosingTarget(name); t != nil {
+					switch t.Stmt.(type) {
+					case *ast.ForStmt, *ast.RangeStmt:
+						valid = true
+					}
+				}
+				if !valid {
+					check.errorf(s.Label.Pos(), "invalid continue label %s", name)
+					return
+				}
+
+			case token.GOTO:
+				if b.gotoTarget(name) == nil {
+					// label may be declared later - add branch to forward jumps
+					fwdJumps = append(fwdJumps, s)
+					return
+				}
+
+			default:
+				check.invalidAST(s.Pos(), "branch statement: %s %s", s.Tok, name)
+				return
+			}
+
+			// record label use
+			obj := all.Lookup(name)
+			obj.(*Label).used = true
+			check.recordUse(s.Label, obj)
+
+		case *ast.AssignStmt:
+			if s.Tok == token.DEFINE {
+				recordVarDecl(s.Pos())
+			}
+
+		case *ast.BlockStmt:
+			blockBranches(lstmt, s.List)
+
+		case *ast.IfStmt:
+			stmtBranches(s.Body)
+			if s.Else != nil {
+				stmtBranches(s.Else)
+			}
+
+		case *ast.CaseClause:
+			blockBranches(nil, s.Body)
+
+		case *ast.SwitchStmt:
+			stmtBranches(s.Body)
+
+		case *ast.TypeSwitchStmt:
+			stmtBranches(s.Body)
+
+		case *ast.CommClause:
+			blockBranches(nil, s.Body)
+
+		case *ast.SelectStmt:
+			stmtBranches(s.Body)
+
+		case *ast.ForStmt:
+			stmtBranches(s.Body)
+
+		case *ast.RangeStmt:
+			stmtBranches(s.Body)
+		}
+	}
+
+	for _, s := range list {
+		stmtBranches(s)
+	}
+
+	return fwdJumps
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/lookup.go

@@ -0,0 +1,341 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements various field and method lookup functions.
+
+package types
+
+// LookupFieldOrMethod looks up a field or method with given package and name
+// in T and returns the corresponding *Var or *Func, an index sequence, and a
+// bool indicating if there were any pointer indirections on the path to the
+// field or method. If addressable is set, T is the type of an addressable
+// variable (only matters for method lookups).
+//
+// The last index entry is the field or method index in the (possibly embedded)
+// type where the entry was found, either:
+//
+//	1) the list of declared methods of a named type; or
+//	2) the list of all methods (method set) of an interface type; or
+//	3) the list of fields of a struct type.
+//
+// The earlier index entries are the indices of the anonymous struct fields
+// traversed to get to the found entry, starting at depth 0.
+//
+// If no entry is found, a nil object is returned. In this case, the returned
+// index and indirect values have the following meaning:
+//
+//	- If index != nil, the index sequence points to an ambiguous entry
+//	(the same name appeared more than once at the same embedding level).
+//
+//	- If indirect is set, a method with a pointer receiver type was found
+//      but there was no pointer on the path from the actual receiver type to
+//	the method's formal receiver base type, nor was the receiver addressable.
+//
+func LookupFieldOrMethod(T Type, addressable bool, pkg *Package, name string) (obj Object, index []int, indirect bool) {
+	// Methods cannot be associated to a named pointer type
+	// (spec: "The type denoted by T is called the receiver base type;
+	// it must not be a pointer or interface type and it must be declared
+	// in the same package as the method.").
+	// Thus, if we have a named pointer type, proceed with the underlying
+	// pointer type but discard the result if it is a method since we would
+	// not have found it for T (see also issue 8590).
+	if t, _ := T.(*Named); t != nil {
+		if p, _ := t.underlying.(*Pointer); p != nil {
+			obj, index, indirect = lookupFieldOrMethod(p, false, pkg, name)
+			if _, ok := obj.(*Func); ok {
+				return nil, nil, false
+			}
+			return
+		}
+	}
+
+	return lookupFieldOrMethod(T, addressable, pkg, name)
+}
+
+// TODO(gri) The named type consolidation and seen maps below must be
+//           indexed by unique keys for a given type. Verify that named
+//           types always have only one representation (even when imported
+//           indirectly via different packages.)
+
+func lookupFieldOrMethod(T Type, addressable bool, pkg *Package, name string) (obj Object, index []int, indirect bool) {
+	// WARNING: The code in this function is extremely subtle - do not modify casually!
+	//          This function and NewMethodSet should be kept in sync.
+
+	if name == "_" {
+		return // blank fields/methods are never found
+	}
+
+	typ, isPtr := deref(T)
+	named, _ := typ.(*Named)
+
+	// *typ where typ is an interface has no methods.
+	if isPtr {
+		utyp := typ
+		if named != nil {
+			utyp = named.underlying
+		}
+		if _, ok := utyp.(*Interface); ok {
+			return
+		}
+	}
+
+	// Start with typ as single entry at shallowest depth.
+	// If typ is not a named type, insert a nil type instead.
+	current := []embeddedType{{named, nil, isPtr, false}}
+
+	// named types that we have seen already, allocated lazily
+	var seen map[*Named]bool
+
+	// search current depth
+	for len(current) > 0 {
+		var next []embeddedType // embedded types found at current depth
+
+		// look for (pkg, name) in all types at current depth
+		for _, e := range current {
+			// The very first time only, e.typ may be nil.
+			// In this case, we don't have a named type and
+			// we simply continue with the underlying type.
+			if e.typ != nil {
+				if seen[e.typ] {
+					// We have seen this type before, at a more shallow depth
+					// (note that multiples of this type at the current depth
+					// were consolidated before). The type at that depth shadows
+					// this same type at the current depth, so we can ignore
+					// this one.
+					continue
+				}
+				if seen == nil {
+					seen = make(map[*Named]bool)
+				}
+				seen[e.typ] = true
+
+				// look for a matching attached method
+				if i, m := lookupMethod(e.typ.methods, pkg, name); m != nil {
+					// potential match
+					assert(m.typ != nil)
+					index = concat(e.index, i)
+					if obj != nil || e.multiples {
+						return nil, index, false // collision
+					}
+					obj = m
+					indirect = e.indirect
+					continue // we can't have a matching field or interface method
+				}
+
+				// continue with underlying type
+				typ = e.typ.underlying
+			}
+
+			switch t := typ.(type) {
+			case *Struct:
+				// look for a matching field and collect embedded types
+				for i, f := range t.fields {
+					if f.sameId(pkg, name) {
+						assert(f.typ != nil)
+						index = concat(e.index, i)
+						if obj != nil || e.multiples {
+							return nil, index, false // collision
+						}
+						obj = f
+						indirect = e.indirect
+						continue // we can't have a matching interface method
+					}
+					// Collect embedded struct fields for searching the next
+					// lower depth, but only if we have not seen a match yet
+					// (if we have a match it is either the desired field or
+					// we have a name collision on the same depth; in either
+					// case we don't need to look further).
+					// Embedded fields are always of the form T or *T where
+					// T is a named type. If e.typ appeared multiple times at
+					// this depth, f.typ appears multiple times at the next
+					// depth.
+					if obj == nil && f.anonymous {
+						// Ignore embedded basic types - only user-defined
+						// named types can have methods or struct fields.
+						typ, isPtr := deref(f.typ)
+						if t, _ := typ.(*Named); t != nil {
+							next = append(next, embeddedType{t, concat(e.index, i), e.indirect || isPtr, e.multiples})
+						}
+					}
+				}
+
+			case *Interface:
+				// look for a matching method
+				// TODO(gri) t.allMethods is sorted - use binary search
+				if i, m := lookupMethod(t.allMethods, pkg, name); m != nil {
+					assert(m.typ != nil)
+					index = concat(e.index, i)
+					if obj != nil || e.multiples {
+						return nil, index, false // collision
+					}
+					obj = m
+					indirect = e.indirect
+				}
+			}
+		}
+
+		if obj != nil {
+			// found a potential match
+			// spec: "A method call x.m() is valid if the method set of (the type of) x
+			//        contains m and the argument list can be assigned to the parameter
+			//        list of m. If x is addressable and &x's method set contains m, x.m()
+			//        is shorthand for (&x).m()".
+			if f, _ := obj.(*Func); f != nil && ptrRecv(f) && !indirect && !addressable {
+				return nil, nil, true // pointer/addressable receiver required
+			}
+			return
+		}
+
+		current = consolidateMultiples(next)
+	}
+
+	return nil, nil, false // not found
+}
+
+// embeddedType represents an embedded named type
+type embeddedType struct {
+	typ       *Named // nil means use the outer typ variable instead
+	index     []int  // embedded field indices, starting with index at depth 0
+	indirect  bool   // if set, there was a pointer indirection on the path to this field
+	multiples bool   // if set, typ appears multiple times at this depth
+}
+
+// consolidateMultiples collects multiple list entries with the same type
+// into a single entry marked as containing multiples. The result is the
+// consolidated list.
+func consolidateMultiples(list []embeddedType) []embeddedType {
+	if len(list) <= 1 {
+		return list // at most one entry - nothing to do
+	}
+
+	n := 0                       // number of entries w/ unique type
+	prev := make(map[*Named]int) // index at which type was previously seen
+	for _, e := range list {
+		if i, found := prev[e.typ]; found {
+			list[i].multiples = true
+			// ignore this entry
+		} else {
+			prev[e.typ] = n
+			list[n] = e
+			n++
+		}
+	}
+	return list[:n]
+}
+
+// MissingMethod returns (nil, false) if V implements T, otherwise it
+// returns a missing method required by T and whether it is missing or
+// just has the wrong type.
+//
+// For non-interface types V, or if static is set, V implements T if all
+// methods of T are present in V. Otherwise (V is an interface and static
+// is not set), MissingMethod only checks that methods of T which are also
+// present in V have matching types (e.g., for a type assertion x.(T) where
+// x is of interface type V).
+//
+func MissingMethod(V Type, T *Interface, static bool) (method *Func, wrongType bool) {
+	// fast path for common case
+	if T.Empty() {
+		return
+	}
+
+	// TODO(gri) Consider using method sets here. Might be more efficient.
+
+	if ityp, _ := V.Underlying().(*Interface); ityp != nil {
+		// TODO(gri) allMethods is sorted - can do this more efficiently
+		for _, m := range T.allMethods {
+			_, obj := lookupMethod(ityp.allMethods, m.pkg, m.name)
+			switch {
+			case obj == nil:
+				if static {
+					return m, false
+				}
+			case !Identical(obj.Type(), m.typ):
+				return m, true
+			}
+		}
+		return
+	}
+
+	// A concrete type implements T if it implements all methods of T.
+	for _, m := range T.allMethods {
+		obj, _, _ := lookupFieldOrMethod(V, false, m.pkg, m.name)
+
+		f, _ := obj.(*Func)
+		if f == nil {
+			return m, false
+		}
+
+		if !Identical(f.typ, m.typ) {
+			return m, true
+		}
+	}
+
+	return
+}
+
+// assertableTo reports whether a value of type V can be asserted to have type T.
+// It returns (nil, false) as affirmative answer. Otherwise it returns a missing
+// method required by V and whether it is missing or just has the wrong type.
+func assertableTo(V *Interface, T Type) (method *Func, wrongType bool) {
+	// no static check is required if T is an interface
+	// spec: "If T is an interface type, x.(T) asserts that the
+	//        dynamic type of x implements the interface T."
+	if _, ok := T.Underlying().(*Interface); ok && !strict {
+		return
+	}
+	return MissingMethod(T, V, false)
+}
+
+// deref dereferences typ if it is a *Pointer and returns its base and true.
+// Otherwise it returns (typ, false).
+func deref(typ Type) (Type, bool) {
+	if p, _ := typ.(*Pointer); p != nil {
+		return p.base, true
+	}
+	return typ, false
+}
+
+// derefStructPtr dereferences typ if it is a (named or unnamed) pointer to a
+// (named or unnamed) struct and returns its base. Otherwise it returns typ.
+func derefStructPtr(typ Type) Type {
+	if p, _ := typ.Underlying().(*Pointer); p != nil {
+		if _, ok := p.base.Underlying().(*Struct); ok {
+			return p.base
+		}
+	}
+	return typ
+}
+
+// concat returns the result of concatenating list and i.
+// The result does not share its underlying array with list.
+func concat(list []int, i int) []int {
+	var t []int
+	t = append(t, list...)
+	return append(t, i)
+}
+
+// fieldIndex returns the index for the field with matching package and name, or a value < 0.
+func fieldIndex(fields []*Var, pkg *Package, name string) int {
+	if name != "_" {
+		for i, f := range fields {
+			if f.sameId(pkg, name) {
+				return i
+			}
+		}
+	}
+	return -1
+}
+
+// lookupMethod returns the index of and method with matching package and name, or (-1, nil).
+func lookupMethod(methods []*Func, pkg *Package, name string) (int, *Func) {
+	if name != "_" {
+		for i, m := range methods {
+			if m.sameId(pkg, name) {
+				return i, m
+			}
+		}
+	}
+	return -1, nil
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/methodset.go

@@ -0,0 +1,271 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements method sets.
+
+package types
+
+import (
+	"bytes"
+	"fmt"
+	"sort"
+)
+
+// A MethodSet is an ordered set of concrete or abstract (interface) methods;
+// a method is a MethodVal selection, and they are ordered by ascending m.Obj().Id().
+// The zero value for a MethodSet is a ready-to-use empty method set.
+type MethodSet struct {
+	list []*Selection
+}
+
+func (s *MethodSet) String() string {
+	if s.Len() == 0 {
+		return "MethodSet {}"
+	}
+
+	var buf bytes.Buffer
+	fmt.Fprintln(&buf, "MethodSet {")
+	for _, f := range s.list {
+		fmt.Fprintf(&buf, "\t%s\n", f)
+	}
+	fmt.Fprintln(&buf, "}")
+	return buf.String()
+}
+
+// Len returns the number of methods in s.
+func (s *MethodSet) Len() int { return len(s.list) }
+
+// At returns the i'th method in s for 0 <= i < s.Len().
+func (s *MethodSet) At(i int) *Selection { return s.list[i] }
+
+// Lookup returns the method with matching package and name, or nil if not found.
+func (s *MethodSet) Lookup(pkg *Package, name string) *Selection {
+	if s.Len() == 0 {
+		return nil
+	}
+
+	key := Id(pkg, name)
+	i := sort.Search(len(s.list), func(i int) bool {
+		m := s.list[i]
+		return m.obj.Id() >= key
+	})
+	if i < len(s.list) {
+		m := s.list[i]
+		if m.obj.Id() == key {
+			return m
+		}
+	}
+	return nil
+}
+
+// Shared empty method set.
+var emptyMethodSet MethodSet
+
+// NewMethodSet returns the method set for the given type T.  It
+// always returns a non-nil method set, even if it is empty.
+//
+// A MethodSetCache handles repeat queries more efficiently.
+//
+func NewMethodSet(T Type) *MethodSet {
+	// WARNING: The code in this function is extremely subtle - do not modify casually!
+	//          This function and lookupFieldOrMethod should be kept in sync.
+
+	// method set up to the current depth, allocated lazily
+	var base methodSet
+
+	typ, isPtr := deref(T)
+	named, _ := typ.(*Named)
+
+	// *typ where typ is an interface has no methods.
+	if isPtr {
+		utyp := typ
+		if named != nil {
+			utyp = named.underlying
+		}
+		if _, ok := utyp.(*Interface); ok {
+			return &emptyMethodSet
+		}
+	}
+
+	// Start with typ as single entry at shallowest depth.
+	// If typ is not a named type, insert a nil type instead.
+	current := []embeddedType{{named, nil, isPtr, false}}
+
+	// named types that we have seen already, allocated lazily
+	var seen map[*Named]bool
+
+	// collect methods at current depth
+	for len(current) > 0 {
+		var next []embeddedType // embedded types found at current depth
+
+		// field and method sets at current depth, allocated lazily
+		var fset fieldSet
+		var mset methodSet
+
+		for _, e := range current {
+			// The very first time only, e.typ may be nil.
+			// In this case, we don't have a named type and
+			// we simply continue with the underlying type.
+			if e.typ != nil {
+				if seen[e.typ] {
+					// We have seen this type before, at a more shallow depth
+					// (note that multiples of this type at the current depth
+					// were consolidated before). The type at that depth shadows
+					// this same type at the current depth, so we can ignore
+					// this one.
+					continue
+				}
+				if seen == nil {
+					seen = make(map[*Named]bool)
+				}
+				seen[e.typ] = true
+
+				mset = mset.add(e.typ.methods, e.index, e.indirect, e.multiples)
+
+				// continue with underlying type
+				typ = e.typ.underlying
+			}
+
+			switch t := typ.(type) {
+			case *Struct:
+				for i, f := range t.fields {
+					fset = fset.add(f, e.multiples)
+
+					// Embedded fields are always of the form T or *T where
+					// T is a named type. If typ appeared multiple times at
+					// this depth, f.Type appears multiple times at the next
+					// depth.
+					if f.anonymous {
+						// Ignore embedded basic types - only user-defined
+						// named types can have methods or struct fields.
+						typ, isPtr := deref(f.typ)
+						if t, _ := typ.(*Named); t != nil {
+							next = append(next, embeddedType{t, concat(e.index, i), e.indirect || isPtr, e.multiples})
+						}
+					}
+				}
+
+			case *Interface:
+				mset = mset.add(t.allMethods, e.index, true, e.multiples)
+			}
+		}
+
+		// Add methods and collisions at this depth to base if no entries with matching
+		// names exist already.
+		for k, m := range mset {
+			if _, found := base[k]; !found {
+				// Fields collide with methods of the same name at this depth.
+				if _, found := fset[k]; found {
+					m = nil // collision
+				}
+				if base == nil {
+					base = make(methodSet)
+				}
+				base[k] = m
+			}
+		}
+
+		// Multiple fields with matching names collide at this depth and shadow all
+		// entries further down; add them as collisions to base if no entries with
+		// matching names exist already.
+		for k, f := range fset {
+			if f == nil {
+				if _, found := base[k]; !found {
+					if base == nil {
+						base = make(methodSet)
+					}
+					base[k] = nil // collision
+				}
+			}
+		}
+
+		current = consolidateMultiples(next)
+	}
+
+	if len(base) == 0 {
+		return &emptyMethodSet
+	}
+
+	// collect methods
+	var list []*Selection
+	for _, m := range base {
+		if m != nil {
+			m.recv = T
+			list = append(list, m)
+		}
+	}
+	sort.Sort(byUniqueName(list))
+	return &MethodSet{list}
+}
+
+// A fieldSet is a set of fields and name collisions.
+// A collision indicates that multiple fields with the
+// same unique id appeared.
+type fieldSet map[string]*Var // a nil entry indicates a name collision
+
+// Add adds field f to the field set s.
+// If multiples is set, f appears multiple times
+// and is treated as a collision.
+func (s fieldSet) add(f *Var, multiples bool) fieldSet {
+	if s == nil {
+		s = make(fieldSet)
+	}
+	key := f.Id()
+	// if f is not in the set, add it
+	if !multiples {
+		if _, found := s[key]; !found {
+			s[key] = f
+			return s
+		}
+	}
+	s[key] = nil // collision
+	return s
+}
+
+// A methodSet is a set of methods and name collisions.
+// A collision indicates that multiple methods with the
+// same unique id appeared.
+type methodSet map[string]*Selection // a nil entry indicates a name collision
+
+// Add adds all functions in list to the method set s.
+// If multiples is set, every function in list appears multiple times
+// and is treated as a collision.
+func (s methodSet) add(list []*Func, index []int, indirect bool, multiples bool) methodSet {
+	if len(list) == 0 {
+		return s
+	}
+	if s == nil {
+		s = make(methodSet)
+	}
+	for i, f := range list {
+		key := f.Id()
+		// if f is not in the set, add it
+		if !multiples {
+			// TODO(gri) A found method may not be added because it's not in the method set
+			// (!indirect && ptrRecv(f)). A 2nd method on the same level may be in the method
+			// set and may not collide with the first one, thus leading to a false positive.
+			// Is that possible? Investigate.
+			if _, found := s[key]; !found && (indirect || !ptrRecv(f)) {
+				s[key] = &Selection{MethodVal, nil, f, concat(index, i), indirect}
+				continue
+			}
+		}
+		s[key] = nil // collision
+	}
+	return s
+}
+
+// ptrRecv reports whether the receiver is of the form *T.
+// The receiver must exist.
+func ptrRecv(f *Func) bool {
+	_, isPtr := deref(f.typ.(*Signature).recv.typ)
+	return isPtr
+}
+
+// byUniqueName function lists can be sorted by their unique names.
+type byUniqueName []*Selection
+
+func (a byUniqueName) Len() int           { return len(a) }
+func (a byUniqueName) Less(i, j int) bool { return a[i].obj.Id() < a[j].obj.Id() }
+func (a byUniqueName) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

Godeps/_workspace/src/golang.org/x/tools/go/types/object.go

@@ -0,0 +1,361 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types
+
+import (
+	"bytes"
+	"fmt"
+	"go/ast"
+	"go/token"
+
+	"golang.org/x/tools/go/exact"
+)
+
+// TODO(gri) Document factory, accessor methods, and fields. General clean-up.
+
+// An Object describes a named language entity such as a package,
+// constant, type, variable, function (incl. methods), or label.
+// All objects implement the Object interface.
+//
+type Object interface {
+	Parent() *Scope // scope in which this object is declared
+	Pos() token.Pos // position of object identifier in declaration
+	Pkg() *Package  // nil for objects in the Universe scope and labels
+	Name() string   // package local object name
+	Type() Type     // object type
+	Exported() bool // reports whether the name starts with a capital letter
+	Id() string     // object id (see Id below)
+
+	// String returns a human-readable string of the object.
+	String() string
+
+	// order reflects a package-level object's source order: if object
+	// a is before object b in the source, then a.order() < b.order().
+	// order returns a value > 0 for package-level objects; it returns
+	// 0 for all other objects (including objects in file scopes).
+	order() uint32
+
+	// setOrder sets the order number of the object. It must be > 0.
+	setOrder(uint32)
+
+	// setParent sets the parent scope of the object.
+	setParent(*Scope)
+
+	// sameId reports whether obj.Id() and Id(pkg, name) are the same.
+	sameId(pkg *Package, name string) bool
+
+	// scopePos returns the start position of the scope of this Object
+	scopePos() token.Pos
+
+	// setScopePos sets the start position of the scope for this Object.
+	setScopePos(pos token.Pos)
+}
+
+// Id returns name if it is exported, otherwise it
+// returns the name qualified with the package path.
+func Id(pkg *Package, name string) string {
+	if ast.IsExported(name) {
+		return name
+	}
+	// unexported names need the package path for differentiation
+	// (if there's no package, make sure we don't start with '.'
+	// as that may change the order of methods between a setup
+	// inside a package and outside a package - which breaks some
+	// tests)
+	path := "_"
+	// TODO(gri): shouldn't !ast.IsExported(name) => pkg != nil be an precondition?
+	// if pkg == nil {
+	// 	panic("nil package in lookup of unexported name")
+	// }
+	if pkg != nil {
+		path = pkg.path
+		if path == "" {
+			path = "_"
+		}
+	}
+	return path + "." + name
+}
+
+// An object implements the common parts of an Object.
+type object struct {
+	parent    *Scope
+	pos       token.Pos
+	pkg       *Package
+	name      string
+	typ       Type
+	order_    uint32
+	scopePos_ token.Pos
+}
+
+func (obj *object) Parent() *Scope      { return obj.parent }
+func (obj *object) Pos() token.Pos      { return obj.pos }
+func (obj *object) Pkg() *Package       { return obj.pkg }
+func (obj *object) Name() string        { return obj.name }
+func (obj *object) Type() Type          { return obj.typ }
+func (obj *object) Exported() bool      { return ast.IsExported(obj.name) }
+func (obj *object) Id() string          { return Id(obj.pkg, obj.name) }
+func (obj *object) String() string      { panic("abstract") }
+func (obj *object) order() uint32       { return obj.order_ }
+func (obj *object) scopePos() token.Pos { return obj.scopePos_ }
+
+func (obj *object) setParent(parent *Scope)   { obj.parent = parent }
+func (obj *object) setOrder(order uint32)     { assert(order > 0); obj.order_ = order }
+func (obj *object) setScopePos(pos token.Pos) { obj.scopePos_ = pos }
+
+func (obj *object) sameId(pkg *Package, name string) bool {
+	// spec:
+	// "Two identifiers are different if they are spelled differently,
+	// or if they appear in different packages and are not exported.
+	// Otherwise, they are the same."
+	if name != obj.name {
+		return false
+	}
+	// obj.Name == name
+	if obj.Exported() {
+		return true
+	}
+	// not exported, so packages must be the same (pkg == nil for
+	// fields in Universe scope; this can only happen for types
+	// introduced via Eval)
+	if pkg == nil || obj.pkg == nil {
+		return pkg == obj.pkg
+	}
+	// pkg != nil && obj.pkg != nil
+	return pkg.path == obj.pkg.path
+}
+
+// A PkgName represents an imported Go package.
+type PkgName struct {
+	object
+	imported *Package
+	used     bool // set if the package was used
+}
+
+func NewPkgName(pos token.Pos, pkg *Package, name string, imported *Package) *PkgName {
+	return &PkgName{object{nil, pos, pkg, name, Typ[Invalid], 0, token.NoPos}, imported, false}
+}
+
+// Imported returns the package that was imported.
+// It is distinct from Pkg(), which is the package containing the import statement.
+func (obj *PkgName) Imported() *Package { return obj.imported }
+
+// A Const represents a declared constant.
+type Const struct {
+	object
+	val     exact.Value
+	visited bool // for initialization cycle detection
+}
+
+func NewConst(pos token.Pos, pkg *Package, name string, typ Type, val exact.Value) *Const {
+	return &Const{object{nil, pos, pkg, name, typ, 0, token.NoPos}, val, false}
+}
+
+func (obj *Const) Val() exact.Value { return obj.val }
+
+// A TypeName represents a declared type.
+type TypeName struct {
+	object
+}
+
+func NewTypeName(pos token.Pos, pkg *Package, name string, typ Type) *TypeName {
+	return &TypeName{object{nil, pos, pkg, name, typ, 0, token.NoPos}}
+}
+
+// A Variable represents a declared variable (including function parameters and results, and struct fields).
+type Var struct {
+	object
+	anonymous bool // if set, the variable is an anonymous struct field, and name is the type name
+	visited   bool // for initialization cycle detection
+	isField   bool // var is struct field
+	used      bool // set if the variable was used
+}
+
+func NewVar(pos token.Pos, pkg *Package, name string, typ Type) *Var {
+	return &Var{object: object{nil, pos, pkg, name, typ, 0, token.NoPos}}
+}
+
+func NewParam(pos token.Pos, pkg *Package, name string, typ Type) *Var {
+	return &Var{object: object{nil, pos, pkg, name, typ, 0, token.NoPos}, used: true} // parameters are always 'used'
+}
+
+func NewField(pos token.Pos, pkg *Package, name string, typ Type, anonymous bool) *Var {
+	return &Var{object: object{nil, pos, pkg, name, typ, 0, token.NoPos}, anonymous: anonymous, isField: true}
+}
+
+func (obj *Var) Anonymous() bool { return obj.anonymous }
+
+func (obj *Var) IsField() bool { return obj.isField }
+
+// A Func represents a declared function, concrete method, or abstract
+// (interface) method.  Its Type() is always a *Signature.
+// An abstract method may belong to many interfaces due to embedding.
+type Func struct {
+	object
+}
+
+func NewFunc(pos token.Pos, pkg *Package, name string, sig *Signature) *Func {
+	// don't store a nil signature
+	var typ Type
+	if sig != nil {
+		typ = sig
+	}
+	return &Func{object{nil, pos, pkg, name, typ, 0, token.NoPos}}
+}
+
+// FullName returns the package- or receiver-type-qualified name of
+// function or method obj.
+func (obj *Func) FullName() string {
+	var buf bytes.Buffer
+	writeFuncName(&buf, obj, nil)
+	return buf.String()
+}
+
+func (obj *Func) Scope() *Scope {
+	return obj.typ.(*Signature).scope
+}
+
+// A Label represents a declared label.
+type Label struct {
+	object
+	used bool // set if the label was used
+}
+
+func NewLabel(pos token.Pos, pkg *Package, name string) *Label {
+	return &Label{object{pos: pos, pkg: pkg, name: name, typ: Typ[Invalid]}, false}
+}
+
+// A Builtin represents a built-in function.
+// Builtins don't have a valid type.
+type Builtin struct {
+	object
+	id builtinId
+}
+
+func newBuiltin(id builtinId) *Builtin {
+	return &Builtin{object{name: predeclaredFuncs[id].name, typ: Typ[Invalid]}, id}
+}
+
+// Nil represents the predeclared value nil.
+type Nil struct {
+	object
+}
+
+func writeObject(buf *bytes.Buffer, obj Object, qf Qualifier) {
+	typ := obj.Type()
+	switch obj := obj.(type) {
+	case *PkgName:
+		fmt.Fprintf(buf, "package %s", obj.Name())
+		if path := obj.imported.path; path != "" && path != obj.name {
+			fmt.Fprintf(buf, " (%q)", path)
+		}
+		return
+
+	case *Const:
+		buf.WriteString("const")
+
+	case *TypeName:
+		buf.WriteString("type")
+		typ = typ.Underlying()
+
+	case *Var:
+		if obj.isField {
+			buf.WriteString("field")
+		} else {
+			buf.WriteString("var")
+		}
+
+	case *Func:
+		buf.WriteString("func ")
+		writeFuncName(buf, obj, qf)
+		if typ != nil {
+			WriteSignature(buf, typ.(*Signature), qf)
+		}
+		return
+
+	case *Label:
+		buf.WriteString("label")
+		typ = nil
+
+	case *Builtin:
+		buf.WriteString("builtin")
+		typ = nil
+
+	case *Nil:
+		buf.WriteString("nil")
+		return
+
+	default:
+		panic(fmt.Sprintf("writeObject(%T)", obj))
+	}
+
+	buf.WriteByte(' ')
+
+	// For package-level objects, qualify the name.
+	if obj.Pkg() != nil && obj.Pkg().scope.Lookup(obj.Name()) == obj {
+		writePackage(buf, obj.Pkg(), qf)
+	}
+	buf.WriteString(obj.Name())
+	if typ != nil {
+		buf.WriteByte(' ')
+		WriteType(buf, typ, qf)
+	}
+}
+
+func writePackage(buf *bytes.Buffer, pkg *Package, qf Qualifier) {
+	if pkg == nil {
+		return
+	}
+	var s string
+	if qf != nil {
+		s = qf(pkg)
+	} else {
+		s = pkg.Path()
+	}
+	if s != "" {
+		buf.WriteString(s)
+		buf.WriteByte('.')
+	}
+}
+
+// ObjectString returns the string form of obj.
+// The Qualifier controls the printing of
+// package-level objects, and may be nil.
+func ObjectString(obj Object, qf Qualifier) string {
+	var buf bytes.Buffer
+	writeObject(&buf, obj, qf)
+	return buf.String()
+}
+
+func (obj *PkgName) String() string  { return ObjectString(obj, nil) }
+func (obj *Const) String() string    { return ObjectString(obj, nil) }
+func (obj *TypeName) String() string { return ObjectString(obj, nil) }
+func (obj *Var) String() string      { return ObjectString(obj, nil) }
+func (obj *Func) String() string     { return ObjectString(obj, nil) }
+func (obj *Label) String() string    { return ObjectString(obj, nil) }
+func (obj *Builtin) String() string  { return ObjectString(obj, nil) }
+func (obj *Nil) String() string      { return ObjectString(obj, nil) }
+
+func writeFuncName(buf *bytes.Buffer, f *Func, qf Qualifier) {
+	if f.typ != nil {
+		sig := f.typ.(*Signature)
+		if recv := sig.Recv(); recv != nil {
+			buf.WriteByte('(')
+			if _, ok := recv.Type().(*Interface); ok {
+				// gcimporter creates abstract methods of
+				// named interfaces using the interface type
+				// (not the named type) as the receiver.
+				// Don't print it in full.
+				buf.WriteString("interface")
+			} else {
+				WriteType(buf, recv.Type(), qf)
+			}
+			buf.WriteByte(')')
+			buf.WriteByte('.')
+		} else if f.pkg != nil {
+			writePackage(buf, f.pkg, qf)
+		}
+	}
+	buf.WriteString(f.name)
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/objset.go

@@ -0,0 +1,31 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements objsets.
+//
+// An objset is similar to a Scope but objset elements
+// are identified by their unique id, instead of their
+// object name.
+
+package types
+
+// An objset is a set of objects identified by their unique id.
+// The zero value for objset is a ready-to-use empty objset.
+type objset map[string]Object // initialized lazily
+
+// insert attempts to insert an object obj into objset s.
+// If s already contains an alternative object alt with
+// the same name, insert leaves s unchanged and returns alt.
+// Otherwise it inserts obj and returns nil.
+func (s *objset) insert(obj Object) Object {
+	id := obj.Id()
+	if alt := (*s)[id]; alt != nil {
+		return alt
+	}
+	if *s == nil {
+		*s = make(map[string]Object)
+	}
+	(*s)[id] = obj
+	return nil
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/operand.go

@@ -0,0 +1,288 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file defines operands and associated operations.
+
+package types
+
+import (
+	"bytes"
+	"go/ast"
+	"go/token"
+
+	"golang.org/x/tools/go/exact"
+)
+
+// An operandMode specifies the (addressing) mode of an operand.
+type operandMode byte
+
+const (
+	invalid  operandMode = iota // operand is invalid
+	novalue                     // operand represents no value (result of a function call w/o result)
+	builtin                     // operand is a built-in function
+	typexpr                     // operand is a type
+	constant                    // operand is a constant; the operand's typ is a Basic type
+	variable                    // operand is an addressable variable
+	mapindex                    // operand is a map index expression (acts like a variable on lhs, commaok on rhs of an assignment)
+	value                       // operand is a computed value
+	commaok                     // like value, but operand may be used in a comma,ok expression
+)
+
+var operandModeString = [...]string{
+	invalid:  "invalid operand",
+	novalue:  "no value",
+	builtin:  "built-in",
+	typexpr:  "type",
+	constant: "constant",
+	variable: "variable",
+	mapindex: "map index expression",
+	value:    "value",
+	commaok:  "comma, ok expression",
+}
+
+// An operand represents an intermediate value during type checking.
+// Operands have an (addressing) mode, the expression evaluating to
+// the operand, the operand's type, a value for constants, and an id
+// for built-in functions.
+// The zero value of operand is a ready to use invalid operand.
+//
+type operand struct {
+	mode operandMode
+	expr ast.Expr
+	typ  Type
+	val  exact.Value
+	id   builtinId
+}
+
+// pos returns the position of the expression corresponding to x.
+// If x is invalid the position is token.NoPos.
+//
+func (x *operand) pos() token.Pos {
+	// x.expr may not be set if x is invalid
+	if x.expr == nil {
+		return token.NoPos
+	}
+	return x.expr.Pos()
+}
+
+// Operand string formats
+// (not all "untyped" cases can appear due to the type system,
+// but they fall out naturally here)
+//
+// mode       format
+//
+// invalid    <expr> (               <mode>                    )
+// novalue    <expr> (               <mode>                    )
+// builtin    <expr> (               <mode>                    )
+// typexpr    <expr> (               <mode>                    )
+//
+// constant   <expr> (<untyped kind> <mode>                    )
+// constant   <expr> (               <mode>       of type <typ>)
+// constant   <expr> (<untyped kind> <mode> <val>              )
+// constant   <expr> (               <mode> <val> of type <typ>)
+//
+// variable   <expr> (<untyped kind> <mode>                    )
+// variable   <expr> (               <mode>       of type <typ>)
+//
+// mapindex   <expr> (<untyped kind> <mode>                    )
+// mapindex   <expr> (               <mode>       of type <typ>)
+//
+// value      <expr> (<untyped kind> <mode>                    )
+// value      <expr> (               <mode>       of type <typ>)
+//
+// commaok    <expr> (<untyped kind> <mode>                    )
+// commaok    <expr> (               <mode>       of type <typ>)
+//
+func operandString(x *operand, qf Qualifier) string {
+	var buf bytes.Buffer
+
+	var expr string
+	if x.expr != nil {
+		expr = ExprString(x.expr)
+	} else {
+		switch x.mode {
+		case builtin:
+			expr = predeclaredFuncs[x.id].name
+		case typexpr:
+			expr = TypeString(x.typ, qf)
+		case constant:
+			expr = x.val.String()
+		}
+	}
+
+	// <expr> (
+	if expr != "" {
+		buf.WriteString(expr)
+		buf.WriteString(" (")
+	}
+
+	// <untyped kind>
+	hasType := false
+	switch x.mode {
+	case invalid, novalue, builtin, typexpr:
+		// no type
+	default:
+		// has type
+		if isUntyped(x.typ) {
+			buf.WriteString(x.typ.(*Basic).name)
+			buf.WriteByte(' ')
+			break
+		}
+		hasType = true
+	}
+
+	// <mode>
+	buf.WriteString(operandModeString[x.mode])
+
+	// <val>
+	if x.mode == constant {
+		if s := x.val.String(); s != expr {
+			buf.WriteByte(' ')
+			buf.WriteString(s)
+		}
+	}
+
+	// <typ>
+	if hasType {
+		if x.typ != Typ[Invalid] {
+			buf.WriteString(" of type ")
+			WriteType(&buf, x.typ, qf)
+		} else {
+			buf.WriteString(" with invalid type")
+		}
+	}
+
+	// )
+	if expr != "" {
+		buf.WriteByte(')')
+	}
+
+	return buf.String()
+}
+
+func (x *operand) String() string {
+	return operandString(x, nil)
+}
+
+// setConst sets x to the untyped constant for literal lit.
+func (x *operand) setConst(tok token.Token, lit string) {
+	val := exact.MakeFromLiteral(lit, tok)
+	if val == nil {
+		// TODO(gri) Should we make it an unknown constant instead?
+		x.mode = invalid
+		return
+	}
+
+	var kind BasicKind
+	switch tok {
+	case token.INT:
+		kind = UntypedInt
+	case token.FLOAT:
+		kind = UntypedFloat
+	case token.IMAG:
+		kind = UntypedComplex
+	case token.CHAR:
+		kind = UntypedRune
+	case token.STRING:
+		kind = UntypedString
+	}
+
+	x.mode = constant
+	x.typ = Typ[kind]
+	x.val = val
+}
+
+// isNil reports whether x is the nil value.
+func (x *operand) isNil() bool {
+	return x.mode == value && x.typ == Typ[UntypedNil]
+}
+
+// TODO(gri) The functions operand.assignableTo, checker.convertUntyped,
+//           checker.representable, and checker.assignment are
+//           overlapping in functionality. Need to simplify and clean up.
+
+// assignableTo reports whether x is assignable to a variable of type T.
+func (x *operand) assignableTo(conf *Config, T Type) bool {
+	if x.mode == invalid || T == Typ[Invalid] {
+		return true // avoid spurious errors
+	}
+
+	V := x.typ
+
+	// x's type is identical to T
+	if Identical(V, T) {
+		return true
+	}
+
+	Vu := V.Underlying()
+	Tu := T.Underlying()
+
+	// T is an interface type and x implements T
+	// (Do this check first as it might succeed early.)
+	if Ti, ok := Tu.(*Interface); ok {
+		if Implements(x.typ, Ti) {
+			return true
+		}
+	}
+
+	// x's type V and T have identical underlying types
+	// and at least one of V or T is not a named type
+	if Identical(Vu, Tu) && (!isNamed(V) || !isNamed(T)) {
+		return true
+	}
+
+	// x is a bidirectional channel value, T is a channel
+	// type, x's type V and T have identical element types,
+	// and at least one of V or T is not a named type
+	if Vc, ok := Vu.(*Chan); ok && Vc.dir == SendRecv {
+		if Tc, ok := Tu.(*Chan); ok && Identical(Vc.elem, Tc.elem) {
+			return !isNamed(V) || !isNamed(T)
+		}
+	}
+
+	// x is the predeclared identifier nil and T is a pointer,
+	// function, slice, map, channel, or interface type
+	if x.isNil() {
+		switch t := Tu.(type) {
+		case *Basic:
+			if t.kind == UnsafePointer {
+				return true
+			}
+		case *Pointer, *Signature, *Slice, *Map, *Chan, *Interface:
+			return true
+		}
+		return false
+	}
+
+	// x is an untyped constant representable by a value of type T
+	// TODO(gri) This is borrowing from checker.convertUntyped and
+	//           checker.representable. Need to clean up.
+	if isUntyped(Vu) {
+		switch t := Tu.(type) {
+		case *Basic:
+			if x.mode == constant {
+				return representableConst(x.val, conf, t.kind, nil)
+			}
+			// The result of a comparison is an untyped boolean,
+			// but may not be a constant.
+			if Vb, _ := Vu.(*Basic); Vb != nil {
+				return Vb.kind == UntypedBool && isBoolean(Tu)
+			}
+		case *Interface:
+			return x.isNil() || t.Empty()
+		case *Pointer, *Signature, *Slice, *Map, *Chan:
+			return x.isNil()
+		}
+	}
+
+	return false
+}
+
+// isInteger reports whether x is a value of integer type
+// or an untyped constant representable as an integer.
+func (x *operand) isInteger() bool {
+	return x.mode == invalid ||
+		isInteger(x.typ) ||
+		isUntyped(x.typ) && x.mode == constant && representableConst(x.val, nil, UntypedInt, nil) // no *Config required for UntypedInt
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/ordering.go

@@ -0,0 +1,127 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements resolveOrder.
+
+package types
+
+import (
+	"go/ast"
+	"sort"
+)
+
+// resolveOrder computes the order in which package-level objects
+// must be type-checked.
+//
+// Interface types appear first in the list, sorted topologically
+// by dependencies on embedded interfaces that are also declared
+// in this package, followed by all other objects sorted in source
+// order.
+//
+// TODO(gri) Consider sorting all types by dependencies here, and
+// in the process check _and_ report type cycles. This may simplify
+// the full type-checking phase.
+//
+func (check *Checker) resolveOrder() []Object {
+	var ifaces, others []Object
+
+	// collect interface types with their dependencies, and all other objects
+	for obj := range check.objMap {
+		if ityp := check.interfaceFor(obj); ityp != nil {
+			ifaces = append(ifaces, obj)
+			// determine dependencies on embedded interfaces
+			for _, f := range ityp.Methods.List {
+				if len(f.Names) == 0 {
+					// Embedded interface: The type must be a (possibly
+					// qualified) identifier denoting another interface.
+					// Imported interfaces are already fully resolved,
+					// so we can ignore qualified identifiers.
+					if ident, _ := f.Type.(*ast.Ident); ident != nil {
+						embedded := check.pkg.scope.Lookup(ident.Name)
+						if check.interfaceFor(embedded) != nil {
+							check.objMap[obj].addDep(embedded)
+						}
+					}
+				}
+			}
+		} else {
+			others = append(others, obj)
+		}
+	}
+
+	// final object order
+	var order []Object
+
+	// sort interface types topologically by dependencies,
+	// and in source order if there are no dependencies
+	sort.Sort(inSourceOrder(ifaces))
+	if debug {
+		for _, obj := range ifaces {
+			assert(check.objMap[obj].mark == 0)
+		}
+	}
+	for _, obj := range ifaces {
+		check.appendInPostOrder(&order, obj)
+	}
+
+	// sort everything else in source order
+	sort.Sort(inSourceOrder(others))
+
+	return append(order, others...)
+}
+
+// interfaceFor returns the AST interface denoted by obj, or nil.
+func (check *Checker) interfaceFor(obj Object) *ast.InterfaceType {
+	tname, _ := obj.(*TypeName)
+	if tname == nil {
+		return nil // not a type
+	}
+	d := check.objMap[obj]
+	if d == nil {
+		check.dump("%s: %s should have been declared", obj.Pos(), obj.Name())
+		unreachable()
+	}
+	if d.typ == nil {
+		return nil // invalid AST - ignore (will be handled later)
+	}
+	ityp, _ := d.typ.(*ast.InterfaceType)
+	return ityp
+}
+
+func (check *Checker) appendInPostOrder(order *[]Object, obj Object) {
+	d := check.objMap[obj]
+	if d.mark != 0 {
+		// We've already seen this object; either because it's
+		// already added to order, or because we have a cycle.
+		// In both cases we stop. Cycle errors are reported
+		// when type-checking types.
+		return
+	}
+	d.mark = 1
+
+	for _, obj := range orderedSetObjects(d.deps) {
+		check.appendInPostOrder(order, obj)
+	}
+
+	*order = append(*order, obj)
+}
+
+func orderedSetObjects(set map[Object]bool) []Object {
+	list := make([]Object, len(set))
+	i := 0
+	for obj := range set {
+		// we don't care about the map element value
+		list[i] = obj
+		i++
+	}
+	sort.Sort(inSourceOrder(list))
+	return list
+}
+
+// inSourceOrder implements the sort.Sort interface.
+type inSourceOrder []Object
+
+func (a inSourceOrder) Len() int           { return len(a) }
+func (a inSourceOrder) Less(i, j int) bool { return a[i].order() < a[j].order() }
+func (a inSourceOrder) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

Godeps/_workspace/src/golang.org/x/tools/go/types/package.go

@@ -0,0 +1,65 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types
+
+import (
+	"fmt"
+	"go/token"
+)
+
+// A Package describes a Go package.
+type Package struct {
+	path     string
+	name     string
+	scope    *Scope
+	complete bool
+	imports  []*Package
+	fake     bool // scope lookup errors are silently dropped if package is fake (internal use only)
+}
+
+// NewPackage returns a new Package for the given package path and name;
+// the name must not be the blank identifier.
+// The package is not complete and contains no explicit imports.
+func NewPackage(path, name string) *Package {
+	if name == "_" {
+		panic("invalid package name _")
+	}
+	scope := NewScope(Universe, token.NoPos, token.NoPos, fmt.Sprintf("package %q", path))
+	return &Package{path: path, name: name, scope: scope}
+}
+
+// Path returns the package path.
+func (pkg *Package) Path() string { return pkg.path }
+
+// Name returns the package name.
+func (pkg *Package) Name() string { return pkg.name }
+
+// Scope returns the (complete or incomplete) package scope
+// holding the objects declared at package level (TypeNames,
+// Consts, Vars, and Funcs).
+func (pkg *Package) Scope() *Scope { return pkg.scope }
+
+// A package is complete if its scope contains (at least) all
+// exported objects; otherwise it is incomplete.
+func (pkg *Package) Complete() bool { return pkg.complete }
+
+// MarkComplete marks a package as complete.
+func (pkg *Package) MarkComplete() { pkg.complete = true }
+
+// Imports returns the list of packages directly imported by
+// pkg; the list is in source order. Package unsafe is excluded.
+//
+// If pkg was loaded from export data, Imports includes packages that
+// provide package-level objects referenced by pkg.  This may be more or
+// less than the set of packages directly imported by pkg's source code.
+func (pkg *Package) Imports() []*Package { return pkg.imports }
+
+// SetImports sets the list of explicitly imported packages to list.
+// It is the caller's responsibility to make sure list elements are unique.
+func (pkg *Package) SetImports(list []*Package) { pkg.imports = list }
+
+func (pkg *Package) String() string {
+	return fmt.Sprintf("package %s (%q)", pkg.name, pkg.path)
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/predicates.go

@@ -0,0 +1,309 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements commonly used type predicates.
+
+package types
+
+import "sort"
+
+func isNamed(typ Type) bool {
+	if _, ok := typ.(*Basic); ok {
+		return ok
+	}
+	_, ok := typ.(*Named)
+	return ok
+}
+
+func isBoolean(typ Type) bool {
+	t, ok := typ.Underlying().(*Basic)
+	return ok && t.info&IsBoolean != 0
+}
+
+func isInteger(typ Type) bool {
+	t, ok := typ.Underlying().(*Basic)
+	return ok && t.info&IsInteger != 0
+}
+
+func isUnsigned(typ Type) bool {
+	t, ok := typ.Underlying().(*Basic)
+	return ok && t.info&IsUnsigned != 0
+}
+
+func isFloat(typ Type) bool {
+	t, ok := typ.Underlying().(*Basic)
+	return ok && t.info&IsFloat != 0
+}
+
+func isComplex(typ Type) bool {
+	t, ok := typ.Underlying().(*Basic)
+	return ok && t.info&IsComplex != 0
+}
+
+func isNumeric(typ Type) bool {
+	t, ok := typ.Underlying().(*Basic)
+	return ok && t.info&IsNumeric != 0
+}
+
+func isString(typ Type) bool {
+	t, ok := typ.Underlying().(*Basic)
+	return ok && t.info&IsString != 0
+}
+
+func isTyped(typ Type) bool {
+	t, ok := typ.Underlying().(*Basic)
+	return !ok || t.info&IsUntyped == 0
+}
+
+func isUntyped(typ Type) bool {
+	t, ok := typ.Underlying().(*Basic)
+	return ok && t.info&IsUntyped != 0
+}
+
+func isOrdered(typ Type) bool {
+	t, ok := typ.Underlying().(*Basic)
+	return ok && t.info&IsOrdered != 0
+}
+
+func isConstType(typ Type) bool {
+	t, ok := typ.Underlying().(*Basic)
+	return ok && t.info&IsConstType != 0
+}
+
+// IsInterface reports whether typ is an interface type.
+func IsInterface(typ Type) bool {
+	_, ok := typ.Underlying().(*Interface)
+	return ok
+}
+
+// Comparable reports whether values of type T are comparable.
+func Comparable(T Type) bool {
+	switch t := T.Underlying().(type) {
+	case *Basic:
+		// assume invalid types to be comparable
+		// to avoid follow-up errors
+		return t.kind != UntypedNil
+	case *Pointer, *Interface, *Chan:
+		return true
+	case *Struct:
+		for _, f := range t.fields {
+			if !Comparable(f.typ) {
+				return false
+			}
+		}
+		return true
+	case *Array:
+		return Comparable(t.elem)
+	}
+	return false
+}
+
+// hasNil reports whether a type includes the nil value.
+func hasNil(typ Type) bool {
+	switch t := typ.Underlying().(type) {
+	case *Basic:
+		return t.kind == UnsafePointer
+	case *Slice, *Pointer, *Signature, *Interface, *Map, *Chan:
+		return true
+	}
+	return false
+}
+
+// Identical reports whether x and y are identical.
+func Identical(x, y Type) bool {
+	return identical(x, y, nil)
+}
+
+// An ifacePair is a node in a stack of interface type pairs compared for identity.
+type ifacePair struct {
+	x, y *Interface
+	prev *ifacePair
+}
+
+func (p *ifacePair) identical(q *ifacePair) bool {
+	return p.x == q.x && p.y == q.y || p.x == q.y && p.y == q.x
+}
+
+func identical(x, y Type, p *ifacePair) bool {
+	if x == y {
+		return true
+	}
+
+	switch x := x.(type) {
+	case *Basic:
+		// Basic types are singletons except for the rune and byte
+		// aliases, thus we cannot solely rely on the x == y check
+		// above.
+		if y, ok := y.(*Basic); ok {
+			return x.kind == y.kind
+		}
+
+	case *Array:
+		// Two array types are identical if they have identical element types
+		// and the same array length.
+		if y, ok := y.(*Array); ok {
+			return x.len == y.len && identical(x.elem, y.elem, p)
+		}
+
+	case *Slice:
+		// Two slice types are identical if they have identical element types.
+		if y, ok := y.(*Slice); ok {
+			return identical(x.elem, y.elem, p)
+		}
+
+	case *Struct:
+		// Two struct types are identical if they have the same sequence of fields,
+		// and if corresponding fields have the same names, and identical types,
+		// and identical tags. Two anonymous fields are considered to have the same
+		// name. Lower-case field names from different packages are always different.
+		if y, ok := y.(*Struct); ok {
+			if x.NumFields() == y.NumFields() {
+				for i, f := range x.fields {
+					g := y.fields[i]
+					if f.anonymous != g.anonymous ||
+						x.Tag(i) != y.Tag(i) ||
+						!f.sameId(g.pkg, g.name) ||
+						!identical(f.typ, g.typ, p) {
+						return false
+					}
+				}
+				return true
+			}
+		}
+
+	case *Pointer:
+		// Two pointer types are identical if they have identical base types.
+		if y, ok := y.(*Pointer); ok {
+			return identical(x.base, y.base, p)
+		}
+
+	case *Tuple:
+		// Two tuples types are identical if they have the same number of elements
+		// and corresponding elements have identical types.
+		if y, ok := y.(*Tuple); ok {
+			if x.Len() == y.Len() {
+				if x != nil {
+					for i, v := range x.vars {
+						w := y.vars[i]
+						if !identical(v.typ, w.typ, p) {
+							return false
+						}
+					}
+				}
+				return true
+			}
+		}
+
+	case *Signature:
+		// Two function types are identical if they have the same number of parameters
+		// and result values, corresponding parameter and result types are identical,
+		// and either both functions are variadic or neither is. Parameter and result
+		// names are not required to match.
+		if y, ok := y.(*Signature); ok {
+			return x.variadic == y.variadic &&
+				identical(x.params, y.params, p) &&
+				identical(x.results, y.results, p)
+		}
+
+	case *Interface:
+		// Two interface types are identical if they have the same set of methods with
+		// the same names and identical function types. Lower-case method names from
+		// different packages are always different. The order of the methods is irrelevant.
+		if y, ok := y.(*Interface); ok {
+			a := x.allMethods
+			b := y.allMethods
+			if len(a) == len(b) {
+				// Interface types are the only types where cycles can occur
+				// that are not "terminated" via named types; and such cycles
+				// can only be created via method parameter types that are
+				// anonymous interfaces (directly or indirectly) embedding
+				// the current interface. Example:
+				//
+				//    type T interface {
+				//        m() interface{T}
+				//    }
+				//
+				// If two such (differently named) interfaces are compared,
+				// endless recursion occurs if the cycle is not detected.
+				//
+				// If x and y were compared before, they must be equal
+				// (if they were not, the recursion would have stopped);
+				// search the ifacePair stack for the same pair.
+				//
+				// This is a quadratic algorithm, but in practice these stacks
+				// are extremely short (bounded by the nesting depth of interface
+				// type declarations that recur via parameter types, an extremely
+				// rare occurrence). An alternative implementation might use a
+				// "visited" map, but that is probably less efficient overall.
+				q := &ifacePair{x, y, p}
+				for p != nil {
+					if p.identical(q) {
+						return true // same pair was compared before
+					}
+					p = p.prev
+				}
+				if debug {
+					assert(sort.IsSorted(byUniqueMethodName(a)))
+					assert(sort.IsSorted(byUniqueMethodName(b)))
+				}
+				for i, f := range a {
+					g := b[i]
+					if f.Id() != g.Id() || !identical(f.typ, g.typ, q) {
+						return false
+					}
+				}
+				return true
+			}
+		}
+
+	case *Map:
+		// Two map types are identical if they have identical key and value types.
+		if y, ok := y.(*Map); ok {
+			return identical(x.key, y.key, p) && identical(x.elem, y.elem, p)
+		}
+
+	case *Chan:
+		// Two channel types are identical if they have identical value types
+		// and the same direction.
+		if y, ok := y.(*Chan); ok {
+			return x.dir == y.dir && identical(x.elem, y.elem, p)
+		}
+
+	case *Named:
+		// Two named types are identical if their type names originate
+		// in the same type declaration.
+		if y, ok := y.(*Named); ok {
+			return x.obj == y.obj
+		}
+
+	default:
+		unreachable()
+	}
+
+	return false
+}
+
+// defaultType returns the default "typed" type for an "untyped" type;
+// it returns the incoming type for all other types. The default type
+// for untyped nil is untyped nil.
+//
+func defaultType(typ Type) Type {
+	if t, ok := typ.(*Basic); ok {
+		switch t.kind {
+		case UntypedBool:
+			return Typ[Bool]
+		case UntypedInt:
+			return Typ[Int]
+		case UntypedRune:
+			return universeRune // use 'rune' name
+		case UntypedFloat:
+			return Typ[Float64]
+		case UntypedComplex:
+			return Typ[Complex128]
+		case UntypedString:
+			return Typ[String]
+		}
+	}
+	return typ
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/resolver.go

@@ -0,0 +1,453 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types
+
+import (
+	"errors"
+	"fmt"
+	"go/ast"
+	"go/token"
+	pathLib "path"
+	"strconv"
+	"strings"
+	"unicode"
+
+	"golang.org/x/tools/go/exact"
+)
+
+// A declInfo describes a package-level const, type, var, or func declaration.
+type declInfo struct {
+	file  *Scope        // scope of file containing this declaration
+	lhs   []*Var        // lhs of n:1 variable declarations, or nil
+	typ   ast.Expr      // type, or nil
+	init  ast.Expr      // init expression, or nil
+	fdecl *ast.FuncDecl // func declaration, or nil
+
+	deps map[Object]bool // type and init dependencies; lazily allocated
+	mark int             // for dependency analysis
+}
+
+// hasInitializer reports whether the declared object has an initialization
+// expression or function body.
+func (d *declInfo) hasInitializer() bool {
+	return d.init != nil || d.fdecl != nil && d.fdecl.Body != nil
+}
+
+// addDep adds obj as a dependency to d.
+func (d *declInfo) addDep(obj Object) {
+	m := d.deps
+	if m == nil {
+		m = make(map[Object]bool)
+		d.deps = m
+	}
+	m[obj] = true
+}
+
+// arityMatch checks that the lhs and rhs of a const or var decl
+// have the appropriate number of names and init exprs. For const
+// decls, init is the value spec providing the init exprs; for
+// var decls, init is nil (the init exprs are in s in this case).
+func (check *Checker) arityMatch(s, init *ast.ValueSpec) {
+	l := len(s.Names)
+	r := len(s.Values)
+	if init != nil {
+		r = len(init.Values)
+	}
+
+	switch {
+	case init == nil && r == 0:
+		// var decl w/o init expr
+		if s.Type == nil {
+			check.errorf(s.Pos(), "missing type or init expr")
+		}
+	case l < r:
+		if l < len(s.Values) {
+			// init exprs from s
+			n := s.Values[l]
+			check.errorf(n.Pos(), "extra init expr %s", n)
+			// TODO(gri) avoid declared but not used error here
+		} else {
+			// init exprs "inherited"
+			check.errorf(s.Pos(), "extra init expr at %s", init.Pos())
+			// TODO(gri) avoid declared but not used error here
+		}
+	case l > r && (init != nil || r != 1):
+		n := s.Names[r]
+		check.errorf(n.Pos(), "missing init expr for %s", n)
+	}
+}
+
+func validatedImportPath(path string) (string, error) {
+	s, err := strconv.Unquote(path)
+	if err != nil {
+		return "", err
+	}
+	if s == "" {
+		return "", fmt.Errorf("empty string")
+	}
+	const illegalChars = `!"#$%&'()*,:;<=>?[\]^{|}` + "`\uFFFD"
+	for _, r := range s {
+		if !unicode.IsGraphic(r) || unicode.IsSpace(r) || strings.ContainsRune(illegalChars, r) {
+			return s, fmt.Errorf("invalid character %#U", r)
+		}
+	}
+	return s, nil
+}
+
+// declarePkgObj declares obj in the package scope, records its ident -> obj mapping,
+// and updates check.objMap. The object must not be a function or method.
+func (check *Checker) declarePkgObj(ident *ast.Ident, obj Object, d *declInfo) {
+	assert(ident.Name == obj.Name())
+
+	// spec: "A package-scope or file-scope identifier with name init
+	// may only be declared to be a function with this (func()) signature."
+	if ident.Name == "init" {
+		check.errorf(ident.Pos(), "cannot declare init - must be func")
+		return
+	}
+
+	check.declare(check.pkg.scope, ident, obj, token.NoPos)
+	check.objMap[obj] = d
+	obj.setOrder(uint32(len(check.objMap)))
+}
+
+// filename returns a filename suitable for debugging output.
+func (check *Checker) filename(fileNo int) string {
+	file := check.files[fileNo]
+	if pos := file.Pos(); pos.IsValid() {
+		return check.fset.File(pos).Name()
+	}
+	return fmt.Sprintf("file[%d]", fileNo)
+}
+
+// collectObjects collects all file and package objects and inserts them
+// into their respective scopes. It also performs imports and associates
+// methods with receiver base type names.
+func (check *Checker) collectObjects() {
+	pkg := check.pkg
+
+	importer := check.conf.Import
+	if importer == nil {
+		if DefaultImport != nil {
+			importer = DefaultImport
+		} else {
+			// Panic if we encounter an import.
+			importer = func(map[string]*Package, string) (*Package, error) {
+				panic(`no Config.Import or DefaultImport (missing import _ "golang.org/x/tools/go/gcimporter"?)`)
+			}
+		}
+	}
+
+	// pkgImports is the set of packages already imported by any package file seen
+	// so far. Used to avoid duplicate entries in pkg.imports. Allocate and populate
+	// it (pkg.imports may not be empty if we are checking test files incrementally).
+	var pkgImports = make(map[*Package]bool)
+	for _, imp := range pkg.imports {
+		pkgImports[imp] = true
+	}
+
+	for fileNo, file := range check.files {
+		// The package identifier denotes the current package,
+		// but there is no corresponding package object.
+		check.recordDef(file.Name, nil)
+
+		// Use the actual source file extent rather than *ast.File extent since the
+		// latter doesn't include comments which appear at the start or end of the file.
+		// Be conservative and use the *ast.File extent if we don't have a *token.File.
+		pos, end := file.Pos(), file.End()
+		if f := check.fset.File(file.Pos()); f != nil {
+			pos, end = token.Pos(f.Base()), token.Pos(f.Base()+f.Size())
+		}
+		fileScope := NewScope(check.pkg.scope, pos, end, check.filename(fileNo))
+		check.recordScope(file, fileScope)
+
+		for _, decl := range file.Decls {
+			switch d := decl.(type) {
+			case *ast.BadDecl:
+				// ignore
+
+			case *ast.GenDecl:
+				var last *ast.ValueSpec // last ValueSpec with type or init exprs seen
+				for iota, spec := range d.Specs {
+					switch s := spec.(type) {
+					case *ast.ImportSpec:
+						// import package
+						var imp *Package
+						path, err := validatedImportPath(s.Path.Value)
+						if err != nil {
+							check.errorf(s.Path.Pos(), "invalid import path (%s)", err)
+							continue
+						}
+						if path == "C" && check.conf.FakeImportC {
+							// TODO(gri) shouldn't create a new one each time
+							imp = NewPackage("C", "C")
+							imp.fake = true
+						} else {
+							var err error
+							imp, err = importer(check.conf.Packages, path)
+							if imp == nil && err == nil {
+								err = errors.New("Config.Import returned nil but no error")
+							}
+							if err != nil {
+								check.errorf(s.Path.Pos(), "could not import %s (%s)", path, err)
+								continue
+							}
+						}
+
+						// add package to list of explicit imports
+						// (this functionality is provided as a convenience
+						// for clients; it is not needed for type-checking)
+						if !pkgImports[imp] {
+							pkgImports[imp] = true
+							if imp != Unsafe {
+								pkg.imports = append(pkg.imports, imp)
+							}
+						}
+
+						// local name overrides imported package name
+						name := imp.name
+						if s.Name != nil {
+							name = s.Name.Name
+							if name == "init" {
+								check.errorf(s.Name.Pos(), "cannot declare init - must be func")
+								continue
+							}
+						}
+
+						obj := NewPkgName(s.Pos(), pkg, name, imp)
+						if s.Name != nil {
+							// in a dot-import, the dot represents the package
+							check.recordDef(s.Name, obj)
+						} else {
+							check.recordImplicit(s, obj)
+						}
+
+						// add import to file scope
+						if name == "." {
+							// merge imported scope with file scope
+							for _, obj := range imp.scope.elems {
+								// A package scope may contain non-exported objects,
+								// do not import them!
+								if obj.Exported() {
+									// TODO(gri) When we import a package, we create
+									// a new local package object. We should do the
+									// same for each dot-imported object. That way
+									// they can have correct position information.
+									// (We must not modify their existing position
+									// information because the same package - found
+									// via Config.Packages - may be dot-imported in
+									// another package!)
+									check.declare(fileScope, nil, obj, token.NoPos)
+									check.recordImplicit(s, obj)
+								}
+							}
+							// add position to set of dot-import positions for this file
+							// (this is only needed for "imported but not used" errors)
+							check.addUnusedDotImport(fileScope, imp, s.Pos())
+						} else {
+							// declare imported package object in file scope
+							check.declare(fileScope, nil, obj, token.NoPos)
+						}
+
+					case *ast.ValueSpec:
+						switch d.Tok {
+						case token.CONST:
+							// determine which initialization expressions to use
+							switch {
+							case s.Type != nil || len(s.Values) > 0:
+								last = s
+							case last == nil:
+								last = new(ast.ValueSpec) // make sure last exists
+							}
+
+							// declare all constants
+							for i, name := range s.Names {
+								obj := NewConst(name.Pos(), pkg, name.Name, nil, exact.MakeInt64(int64(iota)))
+
+								var init ast.Expr
+								if i < len(last.Values) {
+									init = last.Values[i]
+								}
+
+								d := &declInfo{file: fileScope, typ: last.Type, init: init}
+								check.declarePkgObj(name, obj, d)
+							}
+
+							check.arityMatch(s, last)
+
+						case token.VAR:
+							lhs := make([]*Var, len(s.Names))
+							// If there's exactly one rhs initializer, use
+							// the same declInfo d1 for all lhs variables
+							// so that each lhs variable depends on the same
+							// rhs initializer (n:1 var declaration).
+							var d1 *declInfo
+							if len(s.Values) == 1 {
+								// The lhs elements are only set up after the for loop below,
+								// but that's ok because declareVar only collects the declInfo
+								// for a later phase.
+								d1 = &declInfo{file: fileScope, lhs: lhs, typ: s.Type, init: s.Values[0]}
+							}
+
+							// declare all variables
+							for i, name := range s.Names {
+								obj := NewVar(name.Pos(), pkg, name.Name, nil)
+								lhs[i] = obj
+
+								d := d1
+								if d == nil {
+									// individual assignments
+									var init ast.Expr
+									if i < len(s.Values) {
+										init = s.Values[i]
+									}
+									d = &declInfo{file: fileScope, typ: s.Type, init: init}
+								}
+
+								check.declarePkgObj(name, obj, d)
+							}
+
+							check.arityMatch(s, nil)
+
+						default:
+							check.invalidAST(s.Pos(), "invalid token %s", d.Tok)
+						}
+
+					case *ast.TypeSpec:
+						obj := NewTypeName(s.Name.Pos(), pkg, s.Name.Name, nil)
+						check.declarePkgObj(s.Name, obj, &declInfo{file: fileScope, typ: s.Type})
+
+					default:
+						check.invalidAST(s.Pos(), "unknown ast.Spec node %T", s)
+					}
+				}
+
+			case *ast.FuncDecl:
+				name := d.Name.Name
+				obj := NewFunc(d.Name.Pos(), pkg, name, nil)
+				if d.Recv == nil {
+					// regular function
+					if name == "init" {
+						// don't declare init functions in the package scope - they are invisible
+						obj.parent = pkg.scope
+						check.recordDef(d.Name, obj)
+						// init functions must have a body
+						if d.Body == nil {
+							check.softErrorf(obj.pos, "missing function body")
+						}
+					} else {
+						check.declare(pkg.scope, d.Name, obj, token.NoPos)
+					}
+				} else {
+					// method
+					check.recordDef(d.Name, obj)
+					// Associate method with receiver base type name, if possible.
+					// Ignore methods that have an invalid receiver, or a blank _
+					// receiver name. They will be type-checked later, with regular
+					// functions.
+					if list := d.Recv.List; len(list) > 0 {
+						typ := list[0].Type
+						if ptr, _ := typ.(*ast.StarExpr); ptr != nil {
+							typ = ptr.X
+						}
+						if base, _ := typ.(*ast.Ident); base != nil && base.Name != "_" {
+							check.assocMethod(base.Name, obj)
+						}
+					}
+				}
+				info := &declInfo{file: fileScope, fdecl: d}
+				check.objMap[obj] = info
+				obj.setOrder(uint32(len(check.objMap)))
+
+			default:
+				check.invalidAST(d.Pos(), "unknown ast.Decl node %T", d)
+			}
+		}
+	}
+
+	// verify that objects in package and file scopes have different names
+	for _, scope := range check.pkg.scope.children /* file scopes */ {
+		for _, obj := range scope.elems {
+			if alt := pkg.scope.Lookup(obj.Name()); alt != nil {
+				if pkg, ok := obj.(*PkgName); ok {
+					check.errorf(alt.Pos(), "%s already declared through import of %s", alt.Name(), pkg.Imported())
+					check.reportAltDecl(pkg)
+				} else {
+					check.errorf(alt.Pos(), "%s already declared through dot-import of %s", alt.Name(), obj.Pkg())
+					// TODO(gri) dot-imported objects don't have a position; reportAltDecl won't print anything
+					check.reportAltDecl(obj)
+				}
+			}
+		}
+	}
+}
+
+// packageObjects typechecks all package objects in objList, but not function bodies.
+func (check *Checker) packageObjects(objList []Object) {
+	// add new methods to already type-checked types (from a prior Checker.Files call)
+	for _, obj := range objList {
+		if obj, _ := obj.(*TypeName); obj != nil && obj.typ != nil {
+			check.addMethodDecls(obj)
+		}
+	}
+
+	// pre-allocate space for type declaration paths so that the underlying array is reused
+	typePath := make([]*TypeName, 0, 8)
+
+	for _, obj := range objList {
+		check.objDecl(obj, nil, typePath)
+	}
+
+	// At this point we may have a non-empty check.methods map; this means that not all
+	// entries were deleted at the end of typeDecl because the respective receiver base
+	// types were not found. In that case, an error was reported when declaring those
+	// methods. We can now safely discard this map.
+	check.methods = nil
+}
+
+// functionBodies typechecks all function bodies.
+func (check *Checker) functionBodies() {
+	for _, f := range check.funcs {
+		check.funcBody(f.decl, f.name, f.sig, f.body)
+	}
+}
+
+// unusedImports checks for unused imports.
+func (check *Checker) unusedImports() {
+	// if function bodies are not checked, packages' uses are likely missing - don't check
+	if check.conf.IgnoreFuncBodies {
+		return
+	}
+
+	// spec: "It is illegal (...) to directly import a package without referring to
+	// any of its exported identifiers. To import a package solely for its side-effects
+	// (initialization), use the blank identifier as explicit package name."
+
+	// check use of regular imported packages
+	for _, scope := range check.pkg.scope.children /* file scopes */ {
+		for _, obj := range scope.elems {
+			if obj, ok := obj.(*PkgName); ok {
+				// Unused "blank imports" are automatically ignored
+				// since _ identifiers are not entered into scopes.
+				if !obj.used {
+					path := obj.imported.path
+					base := pathLib.Base(path)
+					if obj.name == base {
+						check.softErrorf(obj.pos, "%q imported but not used", path)
+					} else {
+						check.softErrorf(obj.pos, "%q imported but not used as %s", path, obj.name)
+					}
+				}
+			}
+		}
+	}
+
+	// check use of dot-imported packages
+	for _, unusedDotImports := range check.unusedDotImports {
+		for pkg, pos := range unusedDotImports {
+			check.softErrorf(pos, "%q imported but not used", pkg.path)
+		}
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/resolver_test.go

@@ -0,0 +1,189 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types_test
+
+import (
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"sort"
+	"testing"
+
+	_ "golang.org/x/tools/go/gcimporter"
+	. "golang.org/x/tools/go/types"
+)
+
+func TestResolveIdents(t *testing.T) {
+	skipSpecialPlatforms(t)
+
+	sources := []string{
+		`
+		package p
+		import "fmt"
+		import "math"
+		const pi = math.Pi
+		func sin(x float64) float64 {
+			return math.Sin(x)
+		}
+		var Println = fmt.Println
+		`,
+		`
+		package p
+		import "fmt"
+		type errorStringer struct { fmt.Stringer; error }
+		func f() string {
+			_ = "foo"
+			return fmt.Sprintf("%d", g())
+		}
+		func g() (x int) { return }
+		`,
+		`
+		package p
+		import . "go/parser"
+		import "sync"
+		func h() Mode { return ImportsOnly }
+		var _, x int = 1, 2
+		func init() {}
+		type T struct{ *sync.Mutex; a, b, c int}
+		type I interface{ m() }
+		var _ = T{a: 1, b: 2, c: 3}
+		func (_ T) m() {}
+		func (T) _() {}
+		var i I
+		var _ = i.m
+		func _(s []int) { for i, x := range s { _, _ = i, x } }
+		func _(x interface{}) {
+			switch x := x.(type) {
+			case int:
+				_ = x
+			}
+			switch {} // implicit 'true' tag
+		}
+		`,
+		`
+		package p
+		type S struct{}
+		func (T) _() {}
+		func (T) _() {}
+		`,
+		`
+		package p
+		func _() {
+		L0:
+		L1:
+			goto L0
+			for {
+				goto L1
+			}
+			if true {
+				goto L2
+			}
+		L2:
+		}
+		`,
+	}
+
+	pkgnames := []string{
+		"fmt",
+		"math",
+	}
+
+	// parse package files
+	fset := token.NewFileSet()
+	var files []*ast.File
+	for i, src := range sources {
+		f, err := parser.ParseFile(fset, fmt.Sprintf("sources[%d]", i), src, parser.DeclarationErrors)
+		if err != nil {
+			t.Fatal(err)
+		}
+		files = append(files, f)
+	}
+
+	// resolve and type-check package AST
+	var conf Config
+	uses := make(map[*ast.Ident]Object)
+	defs := make(map[*ast.Ident]Object)
+	_, err := conf.Check("testResolveIdents", fset, files, &Info{Defs: defs, Uses: uses})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// check that all packages were imported
+	for _, name := range pkgnames {
+		if conf.Packages[name] == nil {
+			t.Errorf("package %s not imported", name)
+		}
+	}
+
+	// check that qualified identifiers are resolved
+	for _, f := range files {
+		ast.Inspect(f, func(n ast.Node) bool {
+			if s, ok := n.(*ast.SelectorExpr); ok {
+				if x, ok := s.X.(*ast.Ident); ok {
+					obj := uses[x]
+					if obj == nil {
+						t.Errorf("%s: unresolved qualified identifier %s", fset.Position(x.Pos()), x.Name)
+						return false
+					}
+					if _, ok := obj.(*PkgName); ok && uses[s.Sel] == nil {
+						t.Errorf("%s: unresolved selector %s", fset.Position(s.Sel.Pos()), s.Sel.Name)
+						return false
+					}
+					return false
+				}
+				return false
+			}
+			return true
+		})
+	}
+
+	for id, obj := range uses {
+		if obj == nil {
+			t.Errorf("%s: Uses[%s] == nil", fset.Position(id.Pos()), id.Name)
+		}
+	}
+
+	// check that each identifier in the source is found in uses or defs or both
+	var both []string
+	for _, f := range files {
+		ast.Inspect(f, func(n ast.Node) bool {
+			if x, ok := n.(*ast.Ident); ok {
+				var objects int
+				if _, found := uses[x]; found {
+					objects |= 1
+					delete(uses, x)
+				}
+				if _, found := defs[x]; found {
+					objects |= 2
+					delete(defs, x)
+				}
+				if objects == 0 {
+					t.Errorf("%s: unresolved identifier %s", fset.Position(x.Pos()), x.Name)
+				} else if objects == 3 {
+					both = append(both, x.Name)
+				}
+				return false
+			}
+			return true
+		})
+	}
+
+	// check the expected set of idents that are simultaneously uses and defs
+	sort.Strings(both)
+	if got, want := fmt.Sprint(both), "[Mutex Stringer error]"; got != want {
+		t.Errorf("simultaneous uses/defs = %s, want %s", got, want)
+	}
+
+	// any left-over identifiers didn't exist in the source
+	for x := range uses {
+		t.Errorf("%s: identifier %s not present in source", fset.Position(x.Pos()), x.Name)
+	}
+	for x := range defs {
+		t.Errorf("%s: identifier %s not present in source", fset.Position(x.Pos()), x.Name)
+	}
+
+	// TODO(gri) add tests to check ImplicitObj callbacks
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/return.go

@@ -0,0 +1,185 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements isTerminating.
+
+package types
+
+import (
+	"go/ast"
+	"go/token"
+)
+
+// isTerminating reports if s is a terminating statement.
+// If s is labeled, label is the label name; otherwise s
+// is "".
+func (check *Checker) isTerminating(s ast.Stmt, label string) bool {
+	switch s := s.(type) {
+	default:
+		unreachable()
+
+	case *ast.BadStmt, *ast.DeclStmt, *ast.EmptyStmt, *ast.SendStmt,
+		*ast.IncDecStmt, *ast.AssignStmt, *ast.GoStmt, *ast.DeferStmt,
+		*ast.RangeStmt:
+		// no chance
+
+	case *ast.LabeledStmt:
+		return check.isTerminating(s.Stmt, s.Label.Name)
+
+	case *ast.ExprStmt:
+		// the predeclared (possibly parenthesized) panic() function is terminating
+		if call, _ := unparen(s.X).(*ast.CallExpr); call != nil {
+			if id, _ := call.Fun.(*ast.Ident); id != nil {
+				if _, obj := check.scope.LookupParent(id.Name, token.NoPos); obj != nil {
+					if b, _ := obj.(*Builtin); b != nil && b.id == _Panic {
+						return true
+					}
+				}
+			}
+		}
+
+	case *ast.ReturnStmt:
+		return true
+
+	case *ast.BranchStmt:
+		if s.Tok == token.GOTO || s.Tok == token.FALLTHROUGH {
+			return true
+		}
+
+	case *ast.BlockStmt:
+		return check.isTerminatingList(s.List, "")
+
+	case *ast.IfStmt:
+		if s.Else != nil &&
+			check.isTerminating(s.Body, "") &&
+			check.isTerminating(s.Else, "") {
+			return true
+		}
+
+	case *ast.SwitchStmt:
+		return check.isTerminatingSwitch(s.Body, label)
+
+	case *ast.TypeSwitchStmt:
+		return check.isTerminatingSwitch(s.Body, label)
+
+	case *ast.SelectStmt:
+		for _, s := range s.Body.List {
+			cc := s.(*ast.CommClause)
+			if !check.isTerminatingList(cc.Body, "") || hasBreakList(cc.Body, label, true) {
+				return false
+			}
+
+		}
+		return true
+
+	case *ast.ForStmt:
+		if s.Cond == nil && !hasBreak(s.Body, label, true) {
+			return true
+		}
+	}
+
+	return false
+}
+
+func (check *Checker) isTerminatingList(list []ast.Stmt, label string) bool {
+	n := len(list)
+	return n > 0 && check.isTerminating(list[n-1], label)
+}
+
+func (check *Checker) isTerminatingSwitch(body *ast.BlockStmt, label string) bool {
+	hasDefault := false
+	for _, s := range body.List {
+		cc := s.(*ast.CaseClause)
+		if cc.List == nil {
+			hasDefault = true
+		}
+		if !check.isTerminatingList(cc.Body, "") || hasBreakList(cc.Body, label, true) {
+			return false
+		}
+	}
+	return hasDefault
+}
+
+// TODO(gri) For nested breakable statements, the current implementation of hasBreak
+//	     will traverse the same subtree repeatedly, once for each label. Replace
+//           with a single-pass label/break matching phase.
+
+// hasBreak reports if s is or contains a break statement
+// referring to the label-ed statement or implicit-ly the
+// closest outer breakable statement.
+func hasBreak(s ast.Stmt, label string, implicit bool) bool {
+	switch s := s.(type) {
+	default:
+		unreachable()
+
+	case *ast.BadStmt, *ast.DeclStmt, *ast.EmptyStmt, *ast.ExprStmt,
+		*ast.SendStmt, *ast.IncDecStmt, *ast.AssignStmt, *ast.GoStmt,
+		*ast.DeferStmt, *ast.ReturnStmt:
+		// no chance
+
+	case *ast.LabeledStmt:
+		return hasBreak(s.Stmt, label, implicit)
+
+	case *ast.BranchStmt:
+		if s.Tok == token.BREAK {
+			if s.Label == nil {
+				return implicit
+			}
+			if s.Label.Name == label {
+				return true
+			}
+		}
+
+	case *ast.BlockStmt:
+		return hasBreakList(s.List, label, implicit)
+
+	case *ast.IfStmt:
+		if hasBreak(s.Body, label, implicit) ||
+			s.Else != nil && hasBreak(s.Else, label, implicit) {
+			return true
+		}
+
+	case *ast.CaseClause:
+		return hasBreakList(s.Body, label, implicit)
+
+	case *ast.SwitchStmt:
+		if label != "" && hasBreak(s.Body, label, false) {
+			return true
+		}
+
+	case *ast.TypeSwitchStmt:
+		if label != "" && hasBreak(s.Body, label, false) {
+			return true
+		}
+
+	case *ast.CommClause:
+		return hasBreakList(s.Body, label, implicit)
+
+	case *ast.SelectStmt:
+		if label != "" && hasBreak(s.Body, label, false) {
+			return true
+		}
+
+	case *ast.ForStmt:
+		if label != "" && hasBreak(s.Body, label, false) {
+			return true
+		}
+
+	case *ast.RangeStmt:
+		if label != "" && hasBreak(s.Body, label, false) {
+			return true
+		}
+	}
+
+	return false
+}
+
+func hasBreakList(list []ast.Stmt, label string, implicit bool) bool {
+	for _, s := range list {
+		if hasBreak(s, label, implicit) {
+			return true
+		}
+	}
+	return false
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/scope.go

@@ -0,0 +1,190 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements Scopes.
+
+package types
+
+import (
+	"bytes"
+	"fmt"
+	"go/token"
+	"io"
+	"sort"
+	"strings"
+)
+
+// TODO(gri) Provide scopes with a name or other mechanism so that
+//           objects can use that information for better printing.
+
+// A Scope maintains a set of objects and links to its containing
+// (parent) and contained (children) scopes. Objects may be inserted
+// and looked up by name. The zero value for Scope is a ready-to-use
+// empty scope.
+type Scope struct {
+	parent   *Scope
+	children []*Scope
+	elems    map[string]Object // lazily allocated
+	pos, end token.Pos         // scope extent; may be invalid
+	comment  string            // for debugging only
+}
+
+// NewScope returns a new, empty scope contained in the given parent
+// scope, if any.  The comment is for debugging only.
+func NewScope(parent *Scope, pos, end token.Pos, comment string) *Scope {
+	s := &Scope{parent, nil, nil, pos, end, comment}
+	// don't add children to Universe scope!
+	if parent != nil && parent != Universe {
+		parent.children = append(parent.children, s)
+	}
+	return s
+}
+
+// Parent returns the scope's containing (parent) scope.
+func (s *Scope) Parent() *Scope { return s.parent }
+
+// Len() returns the number of scope elements.
+func (s *Scope) Len() int { return len(s.elems) }
+
+// Names returns the scope's element names in sorted order.
+func (s *Scope) Names() []string {
+	names := make([]string, len(s.elems))
+	i := 0
+	for name := range s.elems {
+		names[i] = name
+		i++
+	}
+	sort.Strings(names)
+	return names
+}
+
+// NumChildren() returns the number of scopes nested in s.
+func (s *Scope) NumChildren() int { return len(s.children) }
+
+// Child returns the i'th child scope for 0 <= i < NumChildren().
+func (s *Scope) Child(i int) *Scope { return s.children[i] }
+
+// Lookup returns the object in scope s with the given name if such an
+// object exists; otherwise the result is nil.
+func (s *Scope) Lookup(name string) Object {
+	return s.elems[name]
+}
+
+// LookupParent follows the parent chain of scopes starting with s until
+// it finds a scope where Lookup(name) returns a non-nil object, and then
+// returns that scope and object. If a valid position pos is provided,
+// only objects that were declared at or before pos are considered.
+// If no such scope and object exists, the result is (nil, nil).
+//
+// Note that obj.Parent() may be different from the returned scope if the
+// object was inserted into the scope and already had a parent at that
+// time (see Insert, below). This can only happen for dot-imported objects
+// whose scope is the scope of the package that exported them.
+func (s *Scope) LookupParent(name string, pos token.Pos) (*Scope, Object) {
+	for ; s != nil; s = s.parent {
+		if obj := s.elems[name]; obj != nil && (!pos.IsValid() || obj.scopePos() <= pos) {
+			return s, obj
+		}
+	}
+	return nil, nil
+}
+
+// Insert attempts to insert an object obj into scope s.
+// If s already contains an alternative object alt with
+// the same name, Insert leaves s unchanged and returns alt.
+// Otherwise it inserts obj, sets the object's parent scope
+// if not already set, and returns nil.
+func (s *Scope) Insert(obj Object) Object {
+	name := obj.Name()
+	if alt := s.elems[name]; alt != nil {
+		return alt
+	}
+	if s.elems == nil {
+		s.elems = make(map[string]Object)
+	}
+	s.elems[name] = obj
+	if obj.Parent() == nil {
+		obj.setParent(s)
+	}
+	return nil
+}
+
+// Pos and End describe the scope's source code extent [pos, end).
+// The results are guaranteed to be valid only if the type-checked
+// AST has complete position information. The extent is undefined
+// for Universe and package scopes.
+func (s *Scope) Pos() token.Pos { return s.pos }
+func (s *Scope) End() token.Pos { return s.end }
+
+// Contains returns true if pos is within the scope's extent.
+// The result is guaranteed to be valid only if the type-checked
+// AST has complete position information.
+func (s *Scope) Contains(pos token.Pos) bool {
+	return s.pos <= pos && pos < s.end
+}
+
+// Innermost returns the innermost (child) scope containing
+// pos. If pos is not within any scope, the result is nil.
+// The result is also nil for the Universe scope.
+// The result is guaranteed to be valid only if the type-checked
+// AST has complete position information.
+func (s *Scope) Innermost(pos token.Pos) *Scope {
+	// Package scopes do not have extents since they may be
+	// discontiguous, so iterate over the package's files.
+	if s.parent == Universe {
+		for _, s := range s.children {
+			if inner := s.Innermost(pos); inner != nil {
+				return inner
+			}
+		}
+	}
+
+	if s.Contains(pos) {
+		for _, s := range s.children {
+			if s.Contains(pos) {
+				return s.Innermost(pos)
+			}
+		}
+		return s
+	}
+	return nil
+}
+
+// WriteTo writes a string representation of the scope to w,
+// with the scope elements sorted by name.
+// The level of indentation is controlled by n >= 0, with
+// n == 0 for no indentation.
+// If recurse is set, it also writes nested (children) scopes.
+func (s *Scope) WriteTo(w io.Writer, n int, recurse bool) {
+	const ind = ".  "
+	indn := strings.Repeat(ind, n)
+
+	fmt.Fprintf(w, "%s%s scope %p {", indn, s.comment, s)
+	if len(s.elems) == 0 {
+		fmt.Fprintf(w, "}\n")
+		return
+	}
+
+	fmt.Fprintln(w)
+	indn1 := indn + ind
+	for _, name := range s.Names() {
+		fmt.Fprintf(w, "%s%s\n", indn1, s.elems[name])
+	}
+
+	if recurse {
+		for _, s := range s.children {
+			fmt.Fprintln(w)
+			s.WriteTo(w, n+1, recurse)
+		}
+	}
+
+	fmt.Fprintf(w, "%s}", indn)
+}
+
+// String returns a string representation of the scope, for debugging.
+func (s *Scope) String() string {
+	var buf bytes.Buffer
+	s.WriteTo(&buf, 0, false)
+	return buf.String()
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/selection.go

@@ -0,0 +1,143 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements Selections.
+
+package types
+
+import (
+	"bytes"
+	"fmt"
+)
+
+// SelectionKind describes the kind of a selector expression x.f
+// (excluding qualified identifiers).
+type SelectionKind int
+
+const (
+	FieldVal   SelectionKind = iota // x.f is a struct field selector
+	MethodVal                       // x.f is a method selector
+	MethodExpr                      // x.f is a method expression
+)
+
+// A Selection describes a selector expression x.f.
+// For the declarations:
+//
+//	type T struct{ x int; E }
+//	type E struct{}
+//	func (e E) m() {}
+//	var p *T
+//
+// the following relations exist:
+//
+//	Selector    Kind          Recv    Obj    Type               Index     Indirect
+//
+//	p.x         FieldVal      T       x      int                {0}       true
+//	p.m         MethodVal     *T      m      func (e *T) m()    {1, 0}    true
+//	T.m         MethodExpr    T       m      func m(_ T)        {1, 0}    false
+//
+type Selection struct {
+	kind     SelectionKind
+	recv     Type   // type of x
+	obj      Object // object denoted by x.f
+	index    []int  // path from x to x.f
+	indirect bool   // set if there was any pointer indirection on the path
+}
+
+// Kind returns the selection kind.
+func (s *Selection) Kind() SelectionKind { return s.kind }
+
+// Recv returns the type of x in x.f.
+func (s *Selection) Recv() Type { return s.recv }
+
+// Obj returns the object denoted by x.f; a *Var for
+// a field selection, and a *Func in all other cases.
+func (s *Selection) Obj() Object { return s.obj }
+
+// Type returns the type of x.f, which may be different from the type of f.
+// See Selection for more information.
+func (s *Selection) Type() Type {
+	switch s.kind {
+	case MethodVal:
+		// The type of x.f is a method with its receiver type set
+		// to the type of x.
+		sig := *s.obj.(*Func).typ.(*Signature)
+		recv := *sig.recv
+		recv.typ = s.recv
+		sig.recv = &recv
+		return &sig
+
+	case MethodExpr:
+		// The type of x.f is a function (without receiver)
+		// and an additional first argument with the same type as x.
+		// TODO(gri) Similar code is already in call.go - factor!
+		// TODO(gri) Compute this eagerly to avoid allocations.
+		sig := *s.obj.(*Func).typ.(*Signature)
+		arg0 := *sig.recv
+		sig.recv = nil
+		arg0.typ = s.recv
+		var params []*Var
+		if sig.params != nil {
+			params = sig.params.vars
+		}
+		sig.params = NewTuple(append([]*Var{&arg0}, params...)...)
+		return &sig
+	}
+
+	// In all other cases, the type of x.f is the type of x.
+	return s.obj.Type()
+}
+
+// Index describes the path from x to f in x.f.
+// The last index entry is the field or method index of the type declaring f;
+// either:
+//
+//	1) the list of declared methods of a named type; or
+//	2) the list of methods of an interface type; or
+//	3) the list of fields of a struct type.
+//
+// The earlier index entries are the indices of the embedded fields implicitly
+// traversed to get from (the type of) x to f, starting at embedding depth 0.
+func (s *Selection) Index() []int { return s.index }
+
+// Indirect reports whether any pointer indirection was required to get from
+// x to f in x.f.
+func (s *Selection) Indirect() bool { return s.indirect }
+
+func (s *Selection) String() string { return SelectionString(s, nil) }
+
+// SelectionString returns the string form of s.
+// The Qualifier controls the printing of
+// package-level objects, and may be nil.
+//
+// Examples:
+//	"field (T) f int"
+//	"method (T) f(X) Y"
+//	"method expr (T) f(X) Y"
+//
+func SelectionString(s *Selection, qf Qualifier) string {
+	var k string
+	switch s.kind {
+	case FieldVal:
+		k = "field "
+	case MethodVal:
+		k = "method "
+	case MethodExpr:
+		k = "method expr "
+	default:
+		unreachable()
+	}
+	var buf bytes.Buffer
+	buf.WriteString(k)
+	buf.WriteByte('(')
+	WriteType(&buf, s.Recv(), qf)
+	fmt.Fprintf(&buf, ") %s", s.obj.Name())
+	if T := s.Type(); s.kind == FieldVal {
+		buf.WriteByte(' ')
+		WriteType(&buf, T, qf)
+	} else {
+		WriteSignature(&buf, T.(*Signature), qf)
+	}
+	return buf.String()
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/self_test.go

@@ -0,0 +1,101 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types_test
+
+import (
+	"flag"
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"path/filepath"
+	"testing"
+	"time"
+
+	_ "golang.org/x/tools/go/gcimporter"
+	. "golang.org/x/tools/go/types"
+)
+
+var benchmark = flag.Bool("b", false, "run benchmarks")
+
+func TestSelf(t *testing.T) {
+	fset := token.NewFileSet()
+	files, err := pkgFiles(fset, ".")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, err = Check("go/types", fset, files)
+	if err != nil {
+		// Importing go.tools/go/exact doensn't work in the
+		// build dashboard environment. Don't report an error
+		// for now so that the build remains green.
+		// TODO(gri) fix this
+		t.Log(err) // replace w/ t.Fatal eventually
+		return
+	}
+}
+
+func TestBenchmark(t *testing.T) {
+	if !*benchmark {
+		return
+	}
+
+	// We're not using testing's benchmarking mechanism directly
+	// because we want custom output.
+
+	for _, p := range []string{"types", "exact", "gcimporter"} {
+		path := filepath.Join("..", p)
+		runbench(t, path, false)
+		runbench(t, path, true)
+		fmt.Println()
+	}
+}
+
+func runbench(t *testing.T, path string, ignoreFuncBodies bool) {
+	fset := token.NewFileSet()
+	files, err := pkgFiles(fset, path)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	b := testing.Benchmark(func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			conf := Config{IgnoreFuncBodies: ignoreFuncBodies}
+			conf.Check(path, fset, files, nil)
+		}
+	})
+
+	// determine line count
+	lines := 0
+	fset.Iterate(func(f *token.File) bool {
+		lines += f.LineCount()
+		return true
+	})
+
+	d := time.Duration(b.NsPerOp())
+	fmt.Printf(
+		"%s: %s for %d lines (%d lines/s), ignoreFuncBodies = %v\n",
+		filepath.Base(path), d, lines, int64(float64(lines)/d.Seconds()), ignoreFuncBodies,
+	)
+}
+
+func pkgFiles(fset *token.FileSet, path string) ([]*ast.File, error) {
+	filenames, err := pkgFilenames(path) // from stdlib_test.go
+	if err != nil {
+		return nil, err
+	}
+
+	var files []*ast.File
+	for _, filename := range filenames {
+		file, err := parser.ParseFile(fset, filename, nil, 0)
+		if err != nil {
+			return nil, err
+		}
+		files = append(files, file)
+	}
+
+	return files, nil
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/sizes.go

@@ -0,0 +1,211 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements Sizes.
+
+package types
+
+// Sizes defines the sizing functions for package unsafe.
+type Sizes interface {
+	// Alignof returns the alignment of a variable of type T.
+	// Alignof must implement the alignment guarantees required by the spec.
+	Alignof(T Type) int64
+
+	// Offsetsof returns the offsets of the given struct fields, in bytes.
+	// Offsetsof must implement the offset guarantees required by the spec.
+	Offsetsof(fields []*Var) []int64
+
+	// Sizeof returns the size of a variable of type T.
+	// Sizeof must implement the size guarantees required by the spec.
+	Sizeof(T Type) int64
+}
+
+// StdSizes is a convenience type for creating commonly used Sizes.
+// It makes the following simplifying assumptions:
+//
+//	- The size of explicitly sized basic types (int16, etc.) is the
+//	  specified size.
+//	- The size of strings and interfaces is 2*WordSize.
+//	- The size of slices is 3*WordSize.
+//	- The size of an array of n elements corresponds to the size of
+//	  a struct of n consecutive fields of the array's element type.
+//      - The size of a struct is the offset of the last field plus that
+//	  field's size. As with all element types, if the struct is used
+//	  in an array its size must first be aligned to a multiple of the
+//	  struct's alignment.
+//	- All other types have size WordSize.
+//	- Arrays and structs are aligned per spec definition; all other
+//	  types are naturally aligned with a maximum alignment MaxAlign.
+//
+// *StdSizes implements Sizes.
+//
+type StdSizes struct {
+	WordSize int64 // word size in bytes - must be >= 4 (32bits)
+	MaxAlign int64 // maximum alignment in bytes - must be >= 1
+}
+
+func (s *StdSizes) Alignof(T Type) int64 {
+	// For arrays and structs, alignment is defined in terms
+	// of alignment of the elements and fields, respectively.
+	switch t := T.Underlying().(type) {
+	case *Array:
+		// spec: "For a variable x of array type: unsafe.Alignof(x)
+		// is the same as unsafe.Alignof(x[0]), but at least 1."
+		return s.Alignof(t.elem)
+	case *Struct:
+		// spec: "For a variable x of struct type: unsafe.Alignof(x)
+		// is the largest of the values unsafe.Alignof(x.f) for each
+		// field f of x, but at least 1."
+		max := int64(1)
+		for _, f := range t.fields {
+			if a := s.Alignof(f.typ); a > max {
+				max = a
+			}
+		}
+		return max
+	}
+	a := s.Sizeof(T) // may be 0
+	// spec: "For a variable x of any type: unsafe.Alignof(x) is at least 1."
+	if a < 1 {
+		return 1
+	}
+	if a > s.MaxAlign {
+		return s.MaxAlign
+	}
+	return a
+}
+
+func (s *StdSizes) Offsetsof(fields []*Var) []int64 {
+	offsets := make([]int64, len(fields))
+	var o int64
+	for i, f := range fields {
+		a := s.Alignof(f.typ)
+		o = align(o, a)
+		offsets[i] = o
+		o += s.Sizeof(f.typ)
+	}
+	return offsets
+}
+
+var basicSizes = [...]byte{
+	Bool:       1,
+	Int8:       1,
+	Int16:      2,
+	Int32:      4,
+	Int64:      8,
+	Uint8:      1,
+	Uint16:     2,
+	Uint32:     4,
+	Uint64:     8,
+	Float32:    4,
+	Float64:    8,
+	Complex64:  8,
+	Complex128: 16,
+}
+
+func (s *StdSizes) Sizeof(T Type) int64 {
+	switch t := T.Underlying().(type) {
+	case *Basic:
+		assert(isTyped(T))
+		k := t.kind
+		if int(k) < len(basicSizes) {
+			if s := basicSizes[k]; s > 0 {
+				return int64(s)
+			}
+		}
+		if k == String {
+			return s.WordSize * 2
+		}
+	case *Array:
+		n := t.len
+		if n == 0 {
+			return 0
+		}
+		a := s.Alignof(t.elem)
+		z := s.Sizeof(t.elem)
+		return align(z, a)*(n-1) + z
+	case *Slice:
+		return s.WordSize * 3
+	case *Struct:
+		n := t.NumFields()
+		if n == 0 {
+			return 0
+		}
+		offsets := t.offsets
+		if t.offsets == nil {
+			// compute offsets on demand
+			offsets = s.Offsetsof(t.fields)
+			t.offsets = offsets
+		}
+		return offsets[n-1] + s.Sizeof(t.fields[n-1].typ)
+	case *Interface:
+		return s.WordSize * 2
+	}
+	return s.WordSize // catch-all
+}
+
+// stdSizes is used if Config.Sizes == nil.
+var stdSizes = StdSizes{8, 8}
+
+func (conf *Config) alignof(T Type) int64 {
+	if s := conf.Sizes; s != nil {
+		if a := s.Alignof(T); a >= 1 {
+			return a
+		}
+		panic("Config.Sizes.Alignof returned an alignment < 1")
+	}
+	return stdSizes.Alignof(T)
+}
+
+func (conf *Config) offsetsof(T *Struct) []int64 {
+	offsets := T.offsets
+	if offsets == nil && T.NumFields() > 0 {
+		// compute offsets on demand
+		if s := conf.Sizes; s != nil {
+			offsets = s.Offsetsof(T.fields)
+			// sanity checks
+			if len(offsets) != T.NumFields() {
+				panic("Config.Sizes.Offsetsof returned the wrong number of offsets")
+			}
+			for _, o := range offsets {
+				if o < 0 {
+					panic("Config.Sizes.Offsetsof returned an offset < 0")
+				}
+			}
+		} else {
+			offsets = stdSizes.Offsetsof(T.fields)
+		}
+		T.offsets = offsets
+	}
+	return offsets
+}
+
+// offsetof returns the offset of the field specified via
+// the index sequence relative to typ. All embedded fields
+// must be structs (rather than pointer to structs).
+func (conf *Config) offsetof(typ Type, index []int) int64 {
+	var o int64
+	for _, i := range index {
+		s := typ.Underlying().(*Struct)
+		o += conf.offsetsof(s)[i]
+		typ = s.fields[i].typ
+	}
+	return o
+}
+
+func (conf *Config) sizeof(T Type) int64 {
+	if s := conf.Sizes; s != nil {
+		if z := s.Sizeof(T); z >= 0 {
+			return z
+		}
+		panic("Config.Sizes.Sizeof returned a size < 0")
+	}
+	return stdSizes.Sizeof(T)
+}
+
+// align returns the smallest y >= x such that y % a == 0.
+func align(x, a int64) int64 {
+	y := x + a - 1
+	return y - y%a
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/stdlib_test.go

@@ -0,0 +1,270 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file tests types.Check by using it to
+// typecheck the standard library and tests.
+
+package types_test
+
+import (
+	"fmt"
+	"go/ast"
+	"go/build"
+	"go/parser"
+	"go/scanner"
+	"go/token"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+	"time"
+
+	_ "golang.org/x/tools/go/gcimporter"
+	. "golang.org/x/tools/go/types"
+)
+
+var (
+	pkgCount int // number of packages processed
+	start    = time.Now()
+)
+
+func TestStdlib(t *testing.T) {
+	skipSpecialPlatforms(t)
+
+	walkDirs(t, filepath.Join(runtime.GOROOT(), "src"))
+	if testing.Verbose() {
+		fmt.Println(pkgCount, "packages typechecked in", time.Since(start))
+	}
+}
+
+// firstComment returns the contents of the first comment in
+// the given file, assuming there's one within the first KB.
+func firstComment(filename string) string {
+	f, err := os.Open(filename)
+	if err != nil {
+		return ""
+	}
+	defer f.Close()
+
+	var src [1 << 10]byte // read at most 1KB
+	n, _ := f.Read(src[:])
+
+	var s scanner.Scanner
+	s.Init(fset.AddFile("", fset.Base(), n), src[:n], nil, scanner.ScanComments)
+	for {
+		_, tok, lit := s.Scan()
+		switch tok {
+		case token.COMMENT:
+			// remove trailing */ of multi-line comment
+			if lit[1] == '*' {
+				lit = lit[:len(lit)-2]
+			}
+			return strings.TrimSpace(lit[2:])
+		case token.EOF:
+			return ""
+		}
+	}
+}
+
+func testTestDir(t *testing.T, path string, ignore ...string) {
+	files, err := ioutil.ReadDir(path)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	excluded := make(map[string]bool)
+	for _, filename := range ignore {
+		excluded[filename] = true
+	}
+
+	fset := token.NewFileSet()
+	for _, f := range files {
+		// filter directory contents
+		if f.IsDir() || !strings.HasSuffix(f.Name(), ".go") || excluded[f.Name()] {
+			continue
+		}
+
+		// get per-file instructions
+		expectErrors := false
+		filename := filepath.Join(path, f.Name())
+		if cmd := firstComment(filename); cmd != "" {
+			switch cmd {
+			case "skip", "compiledir":
+				continue // ignore this file
+			case "errorcheck":
+				expectErrors = true
+			}
+		}
+
+		// parse and type-check file
+		file, err := parser.ParseFile(fset, filename, nil, 0)
+		if err == nil {
+			_, err = Check(filename, fset, []*ast.File{file})
+		}
+
+		if expectErrors {
+			if err == nil {
+				t.Errorf("expected errors but found none in %s", filename)
+			}
+		} else {
+			if err != nil {
+				t.Error(err)
+			}
+		}
+	}
+}
+
+func TestStdTest(t *testing.T) {
+	skipSpecialPlatforms(t)
+
+	// test/recover4.go is only built for Linux and Darwin.
+	// TODO(gri) Remove once tests consider +build tags (issue 10370).
+	if runtime.GOOS != "linux" && runtime.GOOS != "darwin" {
+		return
+	}
+
+	testTestDir(t, filepath.Join(runtime.GOROOT(), "test"),
+		"cmplxdivide.go", // also needs file cmplxdivide1.go - ignore
+		"sigchld.go",     // don't work on Windows; testTestDir should consult build tags
+	)
+}
+
+func TestStdFixed(t *testing.T) {
+	skipSpecialPlatforms(t)
+
+	testTestDir(t, filepath.Join(runtime.GOROOT(), "test", "fixedbugs"),
+		"bug248.go", "bug302.go", "bug369.go", // complex test instructions - ignore
+		"bug459.go",      // possibly incorrect test - see issue 6703 (pending spec clarification)
+		"issue3924.go",   // possibly incorrect test - see issue 6671 (pending spec clarification)
+		"issue6889.go",   // gc-specific test
+		"issue7746.go",   // large constants - consumes too much memory
+		"issue11326.go",  // large constants
+		"issue11326b.go", // large constants
+	)
+}
+
+func TestStdKen(t *testing.T) {
+	skipSpecialPlatforms(t)
+
+	testTestDir(t, filepath.Join(runtime.GOROOT(), "test", "ken"))
+}
+
+// Package paths of excluded packages.
+var excluded = map[string]bool{
+	"builtin": true,
+}
+
+// typecheck typechecks the given package files.
+func typecheck(t *testing.T, path string, filenames []string) {
+	fset := token.NewFileSet()
+
+	// parse package files
+	var files []*ast.File
+	for _, filename := range filenames {
+		file, err := parser.ParseFile(fset, filename, nil, parser.AllErrors)
+		if err != nil {
+			// the parser error may be a list of individual errors; report them all
+			if list, ok := err.(scanner.ErrorList); ok {
+				for _, err := range list {
+					t.Error(err)
+				}
+				return
+			}
+			t.Error(err)
+			return
+		}
+
+		if testing.Verbose() {
+			if len(files) == 0 {
+				fmt.Println("package", file.Name.Name)
+			}
+			fmt.Println("\t", filename)
+		}
+
+		files = append(files, file)
+	}
+
+	// typecheck package files
+	var conf Config
+	conf.Error = func(err error) { t.Error(err) }
+	info := Info{Uses: make(map[*ast.Ident]Object)}
+	conf.Check(path, fset, files, &info)
+	pkgCount++
+
+	// Perform checks of API invariants.
+
+	// All Objects have a package, except predeclared ones.
+	errorError := Universe.Lookup("error").Type().Underlying().(*Interface).ExplicitMethod(0) // (error).Error
+	for id, obj := range info.Uses {
+		predeclared := obj == Universe.Lookup(obj.Name()) || obj == errorError
+		if predeclared == (obj.Pkg() != nil) {
+			posn := fset.Position(id.Pos())
+			if predeclared {
+				t.Errorf("%s: predeclared object with package: %s", posn, obj)
+			} else {
+				t.Errorf("%s: user-defined object without package: %s", posn, obj)
+			}
+		}
+	}
+}
+
+// pkgFilenames returns the list of package filenames for the given directory.
+func pkgFilenames(dir string) ([]string, error) {
+	ctxt := build.Default
+	ctxt.CgoEnabled = false
+	pkg, err := ctxt.ImportDir(dir, 0)
+	if err != nil {
+		if _, nogo := err.(*build.NoGoError); nogo {
+			return nil, nil // no *.go files, not an error
+		}
+		return nil, err
+	}
+	if excluded[pkg.ImportPath] {
+		return nil, nil
+	}
+	var filenames []string
+	for _, name := range pkg.GoFiles {
+		filenames = append(filenames, filepath.Join(pkg.Dir, name))
+	}
+	for _, name := range pkg.TestGoFiles {
+		filenames = append(filenames, filepath.Join(pkg.Dir, name))
+	}
+	return filenames, nil
+}
+
+// Note: Could use filepath.Walk instead of walkDirs but that wouldn't
+//       necessarily be shorter or clearer after adding the code to
+//       terminate early for -short tests.
+
+func walkDirs(t *testing.T, dir string) {
+	// limit run time for short tests
+	if testing.Short() && time.Since(start) >= 750*time.Millisecond {
+		return
+	}
+
+	fis, err := ioutil.ReadDir(dir)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+
+	// typecheck package in directory
+	files, err := pkgFilenames(dir)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	if files != nil {
+		typecheck(t, dir, files)
+	}
+
+	// traverse subdirectories, but don't walk into testdata
+	for _, fi := range fis {
+		if fi.IsDir() && fi.Name() != "testdata" {
+			walkDirs(t, filepath.Join(dir, fi.Name()))
+		}
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/stmt.go

@@ -0,0 +1,745 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements typechecking of statements.
+
+package types
+
+import (
+	"fmt"
+	"go/ast"
+	"go/token"
+
+	"golang.org/x/tools/go/exact"
+)
+
+func (check *Checker) funcBody(decl *declInfo, name string, sig *Signature, body *ast.BlockStmt) {
+	if trace {
+		if name == "" {
+			name = "<function literal>"
+		}
+		fmt.Printf("--- %s: %s {\n", name, sig)
+		defer fmt.Println("--- <end>")
+	}
+
+	// set function scope extent
+	sig.scope.pos = body.Pos()
+	sig.scope.end = body.End()
+
+	// save/restore current context and setup function context
+	// (and use 0 indentation at function start)
+	defer func(ctxt context, indent int) {
+		check.context = ctxt
+		check.indent = indent
+	}(check.context, check.indent)
+	check.context = context{
+		decl:  decl,
+		scope: sig.scope,
+		sig:   sig,
+	}
+	check.indent = 0
+
+	check.stmtList(0, body.List)
+
+	if check.hasLabel {
+		check.labels(body)
+	}
+
+	if sig.results.Len() > 0 && !check.isTerminating(body, "") {
+		check.error(body.Rbrace, "missing return")
+	}
+
+	// spec: "Implementation restriction: A compiler may make it illegal to
+	// declare a variable inside a function body if the variable is never used."
+	// (One could check each scope after use, but that distributes this check
+	// over several places because CloseScope is not always called explicitly.)
+	check.usage(sig.scope)
+}
+
+func (check *Checker) usage(scope *Scope) {
+	for _, obj := range scope.elems {
+		if v, _ := obj.(*Var); v != nil && !v.used {
+			check.softErrorf(v.pos, "%s declared but not used", v.name)
+		}
+	}
+	for _, scope := range scope.children {
+		check.usage(scope)
+	}
+}
+
+// stmtContext is a bitset describing which
+// control-flow statements are permissible.
+type stmtContext uint
+
+const (
+	breakOk stmtContext = 1 << iota
+	continueOk
+	fallthroughOk
+)
+
+func (check *Checker) simpleStmt(s ast.Stmt) {
+	if s != nil {
+		check.stmt(0, s)
+	}
+}
+
+func (check *Checker) stmtList(ctxt stmtContext, list []ast.Stmt) {
+	ok := ctxt&fallthroughOk != 0
+	inner := ctxt &^ fallthroughOk
+	for i, s := range list {
+		inner := inner
+		if ok && i+1 == len(list) {
+			inner |= fallthroughOk
+		}
+		check.stmt(inner, s)
+	}
+}
+
+func (check *Checker) multipleDefaults(list []ast.Stmt) {
+	var first ast.Stmt
+	for _, s := range list {
+		var d ast.Stmt
+		switch c := s.(type) {
+		case *ast.CaseClause:
+			if len(c.List) == 0 {
+				d = s
+			}
+		case *ast.CommClause:
+			if c.Comm == nil {
+				d = s
+			}
+		default:
+			check.invalidAST(s.Pos(), "case/communication clause expected")
+		}
+		if d != nil {
+			if first != nil {
+				check.errorf(d.Pos(), "multiple defaults (first at %s)", first.Pos())
+			} else {
+				first = d
+			}
+		}
+	}
+}
+
+func (check *Checker) openScope(s ast.Stmt, comment string) {
+	scope := NewScope(check.scope, s.Pos(), s.End(), comment)
+	check.recordScope(s, scope)
+	check.scope = scope
+}
+
+func (check *Checker) closeScope() {
+	check.scope = check.scope.Parent()
+}
+
+func assignOp(op token.Token) token.Token {
+	// token_test.go verifies the token ordering this function relies on
+	if token.ADD_ASSIGN <= op && op <= token.AND_NOT_ASSIGN {
+		return op + (token.ADD - token.ADD_ASSIGN)
+	}
+	return token.ILLEGAL
+}
+
+func (check *Checker) suspendedCall(keyword string, call *ast.CallExpr) {
+	var x operand
+	var msg string
+	switch check.rawExpr(&x, call, nil) {
+	case conversion:
+		msg = "requires function call, not conversion"
+	case expression:
+		msg = "discards result of"
+	case statement:
+		return
+	default:
+		unreachable()
+	}
+	check.errorf(x.pos(), "%s %s %s", keyword, msg, &x)
+}
+
+func (check *Checker) caseValues(x operand /* copy argument (not *operand!) */, values []ast.Expr) {
+	// No duplicate checking for now. See issue 4524.
+	for _, e := range values {
+		var y operand
+		check.expr(&y, e)
+		if y.mode == invalid {
+			return
+		}
+		// TODO(gri) The convertUntyped call pair below appears in other places. Factor!
+		// Order matters: By comparing y against x, error positions are at the case values.
+		check.convertUntyped(&y, x.typ)
+		if y.mode == invalid {
+			return
+		}
+		check.convertUntyped(&x, y.typ)
+		if x.mode == invalid {
+			return
+		}
+		check.comparison(&y, &x, token.EQL)
+	}
+}
+
+func (check *Checker) caseTypes(x *operand, xtyp *Interface, types []ast.Expr, seen map[Type]token.Pos) (T Type) {
+L:
+	for _, e := range types {
+		T = check.typOrNil(e)
+		if T == Typ[Invalid] {
+			continue
+		}
+		// complain about duplicate types
+		// TODO(gri) use a type hash to avoid quadratic algorithm
+		for t, pos := range seen {
+			if T == nil && t == nil || T != nil && t != nil && Identical(T, t) {
+				// talk about "case" rather than "type" because of nil case
+				check.error(e.Pos(), "duplicate case in type switch")
+				check.errorf(pos, "\tprevious case %s", T) // secondary error, \t indented
+				continue L
+			}
+		}
+		seen[T] = e.Pos()
+		if T != nil {
+			check.typeAssertion(e.Pos(), x, xtyp, T)
+		}
+	}
+	return
+}
+
+// stmt typechecks statement s.
+func (check *Checker) stmt(ctxt stmtContext, s ast.Stmt) {
+	// statements cannot use iota in general
+	// (constant declarations set it explicitly)
+	assert(check.iota == nil)
+
+	// statements must end with the same top scope as they started with
+	if debug {
+		defer func(scope *Scope) {
+			// don't check if code is panicking
+			if p := recover(); p != nil {
+				panic(p)
+			}
+			assert(scope == check.scope)
+		}(check.scope)
+	}
+
+	inner := ctxt &^ fallthroughOk
+	switch s := s.(type) {
+	case *ast.BadStmt, *ast.EmptyStmt:
+		// ignore
+
+	case *ast.DeclStmt:
+		check.declStmt(s.Decl)
+
+	case *ast.LabeledStmt:
+		check.hasLabel = true
+		check.stmt(ctxt, s.Stmt)
+
+	case *ast.ExprStmt:
+		// spec: "With the exception of specific built-in functions,
+		// function and method calls and receive operations can appear
+		// in statement context. Such statements may be parenthesized."
+		var x operand
+		kind := check.rawExpr(&x, s.X, nil)
+		var msg string
+		switch x.mode {
+		default:
+			if kind == statement {
+				return
+			}
+			msg = "is not used"
+		case builtin:
+			msg = "must be called"
+		case typexpr:
+			msg = "is not an expression"
+		}
+		check.errorf(x.pos(), "%s %s", &x, msg)
+
+	case *ast.SendStmt:
+		var ch, x operand
+		check.expr(&ch, s.Chan)
+		check.expr(&x, s.Value)
+		if ch.mode == invalid || x.mode == invalid {
+			return
+		}
+		if tch, ok := ch.typ.Underlying().(*Chan); !ok || tch.dir == RecvOnly || !check.assignment(&x, tch.elem) {
+			if x.mode != invalid {
+				check.invalidOp(ch.pos(), "cannot send %s to channel %s", &x, &ch)
+			}
+		}
+
+	case *ast.IncDecStmt:
+		var op token.Token
+		switch s.Tok {
+		case token.INC:
+			op = token.ADD
+		case token.DEC:
+			op = token.SUB
+		default:
+			check.invalidAST(s.TokPos, "unknown inc/dec operation %s", s.Tok)
+			return
+		}
+		var x operand
+		Y := &ast.BasicLit{ValuePos: s.X.Pos(), Kind: token.INT, Value: "1"} // use x's position
+		check.binary(&x, nil, s.X, Y, op)
+		if x.mode == invalid {
+			return
+		}
+		check.assignVar(s.X, &x)
+
+	case *ast.AssignStmt:
+		switch s.Tok {
+		case token.ASSIGN, token.DEFINE:
+			if len(s.Lhs) == 0 {
+				check.invalidAST(s.Pos(), "missing lhs in assignment")
+				return
+			}
+			if s.Tok == token.DEFINE {
+				check.shortVarDecl(s.TokPos, s.Lhs, s.Rhs)
+			} else {
+				// regular assignment
+				check.assignVars(s.Lhs, s.Rhs)
+			}
+
+		default:
+			// assignment operations
+			if len(s.Lhs) != 1 || len(s.Rhs) != 1 {
+				check.errorf(s.TokPos, "assignment operation %s requires single-valued expressions", s.Tok)
+				return
+			}
+			op := assignOp(s.Tok)
+			if op == token.ILLEGAL {
+				check.invalidAST(s.TokPos, "unknown assignment operation %s", s.Tok)
+				return
+			}
+			var x operand
+			check.binary(&x, nil, s.Lhs[0], s.Rhs[0], op)
+			if x.mode == invalid {
+				return
+			}
+			check.assignVar(s.Lhs[0], &x)
+		}
+
+	case *ast.GoStmt:
+		check.suspendedCall("go", s.Call)
+
+	case *ast.DeferStmt:
+		check.suspendedCall("defer", s.Call)
+
+	case *ast.ReturnStmt:
+		res := check.sig.results
+		if res.Len() > 0 {
+			// function returns results
+			// (if one, say the first, result parameter is named, all of them are named)
+			if len(s.Results) == 0 && res.vars[0].name != "" {
+				// spec: "Implementation restriction: A compiler may disallow an empty expression
+				// list in a "return" statement if a different entity (constant, type, or variable)
+				// with the same name as a result parameter is in scope at the place of the return."
+				for _, obj := range res.vars {
+					if _, alt := check.scope.LookupParent(obj.name, check.pos); alt != nil && alt != obj {
+						check.errorf(s.Pos(), "result parameter %s not in scope at return", obj.name)
+						check.errorf(alt.Pos(), "\tinner declaration of %s", obj)
+						// ok to continue
+					}
+				}
+			} else {
+				// return has results or result parameters are unnamed
+				check.initVars(res.vars, s.Results, s.Return)
+			}
+		} else if len(s.Results) > 0 {
+			check.error(s.Results[0].Pos(), "no result values expected")
+			check.use(s.Results...)
+		}
+
+	case *ast.BranchStmt:
+		if s.Label != nil {
+			check.hasLabel = true
+			return // checked in 2nd pass (check.labels)
+		}
+		switch s.Tok {
+		case token.BREAK:
+			if ctxt&breakOk == 0 {
+				check.error(s.Pos(), "break not in for, switch, or select statement")
+			}
+		case token.CONTINUE:
+			if ctxt&continueOk == 0 {
+				check.error(s.Pos(), "continue not in for statement")
+			}
+		case token.FALLTHROUGH:
+			if ctxt&fallthroughOk == 0 {
+				check.error(s.Pos(), "fallthrough statement out of place")
+			}
+		default:
+			check.invalidAST(s.Pos(), "branch statement: %s", s.Tok)
+		}
+
+	case *ast.BlockStmt:
+		check.openScope(s, "block")
+		defer check.closeScope()
+
+		check.stmtList(inner, s.List)
+
+	case *ast.IfStmt:
+		check.openScope(s, "if")
+		defer check.closeScope()
+
+		check.simpleStmt(s.Init)
+		var x operand
+		check.expr(&x, s.Cond)
+		if x.mode != invalid && !isBoolean(x.typ) {
+			check.error(s.Cond.Pos(), "non-boolean condition in if statement")
+		}
+		check.stmt(inner, s.Body)
+		if s.Else != nil {
+			check.stmt(inner, s.Else)
+		}
+
+	case *ast.SwitchStmt:
+		inner |= breakOk
+		check.openScope(s, "switch")
+		defer check.closeScope()
+
+		check.simpleStmt(s.Init)
+		var x operand
+		if s.Tag != nil {
+			check.expr(&x, s.Tag)
+		} else {
+			// spec: "A missing switch expression is
+			// equivalent to the boolean value true."
+			x.mode = constant
+			x.typ = Typ[Bool]
+			x.val = exact.MakeBool(true)
+			x.expr = &ast.Ident{NamePos: s.Body.Lbrace, Name: "true"}
+		}
+
+		check.multipleDefaults(s.Body.List)
+
+		for i, c := range s.Body.List {
+			clause, _ := c.(*ast.CaseClause)
+			if clause == nil {
+				check.invalidAST(c.Pos(), "incorrect expression switch case")
+				continue
+			}
+			if x.mode != invalid {
+				check.caseValues(x, clause.List)
+			}
+			check.openScope(clause, "case")
+			inner := inner
+			if i+1 < len(s.Body.List) {
+				inner |= fallthroughOk
+			}
+			check.stmtList(inner, clause.Body)
+			check.closeScope()
+		}
+
+	case *ast.TypeSwitchStmt:
+		inner |= breakOk
+		check.openScope(s, "type switch")
+		defer check.closeScope()
+
+		check.simpleStmt(s.Init)
+
+		// A type switch guard must be of the form:
+		//
+		//     TypeSwitchGuard = [ identifier ":=" ] PrimaryExpr "." "(" "type" ")" .
+		//
+		// The parser is checking syntactic correctness;
+		// remaining syntactic errors are considered AST errors here.
+		// TODO(gri) better factoring of error handling (invalid ASTs)
+		//
+		var lhs *ast.Ident // lhs identifier or nil
+		var rhs ast.Expr
+		switch guard := s.Assign.(type) {
+		case *ast.ExprStmt:
+			rhs = guard.X
+		case *ast.AssignStmt:
+			if len(guard.Lhs) != 1 || guard.Tok != token.DEFINE || len(guard.Rhs) != 1 {
+				check.invalidAST(s.Pos(), "incorrect form of type switch guard")
+				return
+			}
+
+			lhs, _ = guard.Lhs[0].(*ast.Ident)
+			if lhs == nil {
+				check.invalidAST(s.Pos(), "incorrect form of type switch guard")
+				return
+			}
+
+			if lhs.Name == "_" {
+				// _ := x.(type) is an invalid short variable declaration
+				check.softErrorf(lhs.Pos(), "no new variable on left side of :=")
+				lhs = nil // avoid declared but not used error below
+			} else {
+				check.recordDef(lhs, nil) // lhs variable is implicitly declared in each cause clause
+			}
+
+			rhs = guard.Rhs[0]
+
+		default:
+			check.invalidAST(s.Pos(), "incorrect form of type switch guard")
+			return
+		}
+
+		// rhs must be of the form: expr.(type) and expr must be an interface
+		expr, _ := rhs.(*ast.TypeAssertExpr)
+		if expr == nil || expr.Type != nil {
+			check.invalidAST(s.Pos(), "incorrect form of type switch guard")
+			return
+		}
+		var x operand
+		check.expr(&x, expr.X)
+		if x.mode == invalid {
+			return
+		}
+		xtyp, _ := x.typ.Underlying().(*Interface)
+		if xtyp == nil {
+			check.errorf(x.pos(), "%s is not an interface", &x)
+			return
+		}
+
+		check.multipleDefaults(s.Body.List)
+
+		var lhsVars []*Var               // list of implicitly declared lhs variables
+		seen := make(map[Type]token.Pos) // map of seen types to positions
+		for _, s := range s.Body.List {
+			clause, _ := s.(*ast.CaseClause)
+			if clause == nil {
+				check.invalidAST(s.Pos(), "incorrect type switch case")
+				continue
+			}
+			// Check each type in this type switch case.
+			T := check.caseTypes(&x, xtyp, clause.List, seen)
+			check.openScope(clause, "case")
+			// If lhs exists, declare a corresponding variable in the case-local scope.
+			if lhs != nil {
+				// spec: "The TypeSwitchGuard may include a short variable declaration.
+				// When that form is used, the variable is declared at the beginning of
+				// the implicit block in each clause. In clauses with a case listing
+				// exactly one type, the variable has that type; otherwise, the variable
+				// has the type of the expression in the TypeSwitchGuard."
+				if len(clause.List) != 1 || T == nil {
+					T = x.typ
+				}
+				obj := NewVar(lhs.Pos(), check.pkg, lhs.Name, T)
+				scopePos := clause.End()
+				if len(clause.Body) > 0 {
+					scopePos = clause.Body[0].Pos()
+				}
+				check.declare(check.scope, nil, obj, scopePos)
+				check.recordImplicit(clause, obj)
+				// For the "declared but not used" error, all lhs variables act as
+				// one; i.e., if any one of them is 'used', all of them are 'used'.
+				// Collect them for later analysis.
+				lhsVars = append(lhsVars, obj)
+			}
+			check.stmtList(inner, clause.Body)
+			check.closeScope()
+		}
+
+		// If lhs exists, we must have at least one lhs variable that was used.
+		if lhs != nil {
+			var used bool
+			for _, v := range lhsVars {
+				if v.used {
+					used = true
+				}
+				v.used = true // avoid usage error when checking entire function
+			}
+			if !used {
+				check.softErrorf(lhs.Pos(), "%s declared but not used", lhs.Name)
+			}
+		}
+
+	case *ast.SelectStmt:
+		inner |= breakOk
+
+		check.multipleDefaults(s.Body.List)
+
+		for _, s := range s.Body.List {
+			clause, _ := s.(*ast.CommClause)
+			if clause == nil {
+				continue // error reported before
+			}
+
+			// clause.Comm must be a SendStmt, RecvStmt, or default case
+			valid := false
+			var rhs ast.Expr // rhs of RecvStmt, or nil
+			switch s := clause.Comm.(type) {
+			case nil, *ast.SendStmt:
+				valid = true
+			case *ast.AssignStmt:
+				if len(s.Rhs) == 1 {
+					rhs = s.Rhs[0]
+				}
+			case *ast.ExprStmt:
+				rhs = s.X
+			}
+
+			// if present, rhs must be a receive operation
+			if rhs != nil {
+				if x, _ := unparen(rhs).(*ast.UnaryExpr); x != nil && x.Op == token.ARROW {
+					valid = true
+				}
+			}
+
+			if !valid {
+				check.error(clause.Comm.Pos(), "select case must be send or receive (possibly with assignment)")
+				continue
+			}
+
+			check.openScope(s, "case")
+			if clause.Comm != nil {
+				check.stmt(inner, clause.Comm)
+			}
+			check.stmtList(inner, clause.Body)
+			check.closeScope()
+		}
+
+	case *ast.ForStmt:
+		inner |= breakOk | continueOk
+		check.openScope(s, "for")
+		defer check.closeScope()
+
+		check.simpleStmt(s.Init)
+		if s.Cond != nil {
+			var x operand
+			check.expr(&x, s.Cond)
+			if x.mode != invalid && !isBoolean(x.typ) {
+				check.error(s.Cond.Pos(), "non-boolean condition in for statement")
+			}
+		}
+		check.simpleStmt(s.Post)
+		// spec: "The init statement may be a short variable
+		// declaration, but the post statement must not."
+		if s, _ := s.Post.(*ast.AssignStmt); s != nil && s.Tok == token.DEFINE {
+			check.softErrorf(s.Pos(), "cannot declare in post statement")
+			check.use(s.Lhs...) // avoid follow-up errors
+		}
+		check.stmt(inner, s.Body)
+
+	case *ast.RangeStmt:
+		inner |= breakOk | continueOk
+		check.openScope(s, "for")
+		defer check.closeScope()
+
+		// check expression to iterate over
+		var x operand
+		check.expr(&x, s.X)
+
+		// determine key/value types
+		var key, val Type
+		if x.mode != invalid {
+			switch typ := x.typ.Underlying().(type) {
+			case *Basic:
+				if isString(typ) {
+					key = Typ[Int]
+					val = universeRune // use 'rune' name
+				}
+			case *Array:
+				key = Typ[Int]
+				val = typ.elem
+			case *Slice:
+				key = Typ[Int]
+				val = typ.elem
+			case *Pointer:
+				if typ, _ := typ.base.Underlying().(*Array); typ != nil {
+					key = Typ[Int]
+					val = typ.elem
+				}
+			case *Map:
+				key = typ.key
+				val = typ.elem
+			case *Chan:
+				key = typ.elem
+				val = Typ[Invalid]
+				if typ.dir == SendOnly {
+					check.errorf(x.pos(), "cannot range over send-only channel %s", &x)
+					// ok to continue
+				}
+				if s.Value != nil {
+					check.errorf(s.Value.Pos(), "iteration over %s permits only one iteration variable", &x)
+					// ok to continue
+				}
+			}
+		}
+
+		if key == nil {
+			check.errorf(x.pos(), "cannot range over %s", &x)
+			// ok to continue
+		}
+
+		// check assignment to/declaration of iteration variables
+		// (irregular assignment, cannot easily map to existing assignment checks)
+
+		// lhs expressions and initialization value (rhs) types
+		lhs := [2]ast.Expr{s.Key, s.Value}
+		rhs := [2]Type{key, val} // key, val may be nil
+
+		if s.Tok == token.DEFINE {
+			// short variable declaration; variable scope starts after the range clause
+			// (the for loop opens a new scope, so variables on the lhs never redeclare
+			// previously declared variables)
+			var vars []*Var
+			for i, lhs := range lhs {
+				if lhs == nil {
+					continue
+				}
+
+				// determine lhs variable
+				var obj *Var
+				if ident, _ := lhs.(*ast.Ident); ident != nil {
+					// declare new variable
+					name := ident.Name
+					obj = NewVar(ident.Pos(), check.pkg, name, nil)
+					check.recordDef(ident, obj)
+					// _ variables don't count as new variables
+					if name != "_" {
+						vars = append(vars, obj)
+					}
+				} else {
+					check.errorf(lhs.Pos(), "cannot declare %s", lhs)
+					obj = NewVar(lhs.Pos(), check.pkg, "_", nil) // dummy variable
+				}
+
+				// initialize lhs variable
+				if typ := rhs[i]; typ != nil {
+					x.mode = value
+					x.expr = lhs // we don't have a better rhs expression to use here
+					x.typ = typ
+					check.initVar(obj, &x, false)
+				} else {
+					obj.typ = Typ[Invalid]
+					obj.used = true // don't complain about unused variable
+				}
+			}
+
+			// declare variables
+			if len(vars) > 0 {
+				for _, obj := range vars {
+					// spec: "The scope of a constant or variable identifier declared inside
+					// a function begins at the end of the ConstSpec or VarSpec (ShortVarDecl
+					// for short variable declarations) and ends at the end of the innermost
+					// containing block."
+					scopePos := s.End()
+					check.declare(check.scope, nil /* recordDef already called */, obj, scopePos)
+				}
+			} else {
+				check.error(s.TokPos, "no new variables on left side of :=")
+			}
+		} else {
+			// ordinary assignment
+			for i, lhs := range lhs {
+				if lhs == nil {
+					continue
+				}
+				if typ := rhs[i]; typ != nil {
+					x.mode = value
+					x.expr = lhs // we don't have a better rhs expression to use here
+					x.typ = typ
+					check.assignVar(lhs, &x)
+				}
+			}
+		}
+
+		check.stmt(inner, s.Body)
+
+	default:
+		check.error(s.Pos(), "invalid statement")
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/token_test.go

@@ -0,0 +1,47 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file checks invariants of token.Token ordering that we rely on
+// since package go/token doesn't provide any guarantees at the moment.
+
+package types
+
+import (
+	"go/token"
+	"testing"
+)
+
+var assignOps = map[token.Token]token.Token{
+	token.ADD_ASSIGN:     token.ADD,
+	token.SUB_ASSIGN:     token.SUB,
+	token.MUL_ASSIGN:     token.MUL,
+	token.QUO_ASSIGN:     token.QUO,
+	token.REM_ASSIGN:     token.REM,
+	token.AND_ASSIGN:     token.AND,
+	token.OR_ASSIGN:      token.OR,
+	token.XOR_ASSIGN:     token.XOR,
+	token.SHL_ASSIGN:     token.SHL,
+	token.SHR_ASSIGN:     token.SHR,
+	token.AND_NOT_ASSIGN: token.AND_NOT,
+}
+
+func TestZeroTok(t *testing.T) {
+	// zero value for token.Token must be token.ILLEGAL
+	var zero token.Token
+	if token.ILLEGAL != zero {
+		t.Errorf("%s == %d; want 0", token.ILLEGAL, zero)
+	}
+}
+
+func TestAssignOp(t *testing.T) {
+	// there are fewer than 256 tokens
+	for i := 0; i < 256; i++ {
+		tok := token.Token(i)
+		got := assignOp(tok)
+		want := assignOps[tok]
+		if got != want {
+			t.Errorf("for assignOp(%s): got %s; want %s", tok, got, want)
+		}
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/type.go

@@ -0,0 +1,454 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types
+
+import "sort"
+
+// TODO(gri) Revisit factory functions - make sure they have all relevant parameters.
+
+// A Type represents a type of Go.
+// All types implement the Type interface.
+type Type interface {
+	// Underlying returns the underlying type of a type.
+	Underlying() Type
+
+	// String returns a string representation of a type.
+	String() string
+}
+
+// BasicKind describes the kind of basic type.
+type BasicKind int
+
+const (
+	Invalid BasicKind = iota // type is invalid
+
+	// predeclared types
+	Bool
+	Int
+	Int8
+	Int16
+	Int32
+	Int64
+	Uint
+	Uint8
+	Uint16
+	Uint32
+	Uint64
+	Uintptr
+	Float32
+	Float64
+	Complex64
+	Complex128
+	String
+	UnsafePointer
+
+	// types for untyped values
+	UntypedBool
+	UntypedInt
+	UntypedRune
+	UntypedFloat
+	UntypedComplex
+	UntypedString
+	UntypedNil
+
+	// aliases
+	Byte = Uint8
+	Rune = Int32
+)
+
+// BasicInfo is a set of flags describing properties of a basic type.
+type BasicInfo int
+
+// Properties of basic types.
+const (
+	IsBoolean BasicInfo = 1 << iota
+	IsInteger
+	IsUnsigned
+	IsFloat
+	IsComplex
+	IsString
+	IsUntyped
+
+	IsOrdered   = IsInteger | IsFloat | IsString
+	IsNumeric   = IsInteger | IsFloat | IsComplex
+	IsConstType = IsBoolean | IsNumeric | IsString
+)
+
+// A Basic represents a basic type.
+type Basic struct {
+	kind BasicKind
+	info BasicInfo
+	name string
+}
+
+// Kind returns the kind of basic type b.
+func (b *Basic) Kind() BasicKind { return b.kind }
+
+// Info returns information about properties of basic type b.
+func (b *Basic) Info() BasicInfo { return b.info }
+
+// Name returns the name of basic type b.
+func (b *Basic) Name() string { return b.name }
+
+// An Array represents an array type.
+type Array struct {
+	len  int64
+	elem Type
+}
+
+// NewArray returns a new array type for the given element type and length.
+func NewArray(elem Type, len int64) *Array { return &Array{len, elem} }
+
+// Len returns the length of array a.
+func (a *Array) Len() int64 { return a.len }
+
+// Elem returns element type of array a.
+func (a *Array) Elem() Type { return a.elem }
+
+// A Slice represents a slice type.
+type Slice struct {
+	elem Type
+}
+
+// NewSlice returns a new slice type for the given element type.
+func NewSlice(elem Type) *Slice { return &Slice{elem} }
+
+// Elem returns the element type of slice s.
+func (s *Slice) Elem() Type { return s.elem }
+
+// A Struct represents a struct type.
+type Struct struct {
+	fields []*Var
+	tags   []string // field tags; nil if there are no tags
+	// TODO(gri) access to offsets is not threadsafe - fix this
+	offsets []int64 // field offsets in bytes, lazily initialized
+}
+
+// NewStruct returns a new struct with the given fields and corresponding field tags.
+// If a field with index i has a tag, tags[i] must be that tag, but len(tags) may be
+// only as long as required to hold the tag with the largest index i. Consequently,
+// if no field has a tag, tags may be nil.
+func NewStruct(fields []*Var, tags []string) *Struct {
+	var fset objset
+	for _, f := range fields {
+		if f.name != "_" && fset.insert(f) != nil {
+			panic("multiple fields with the same name")
+		}
+	}
+	if len(tags) > len(fields) {
+		panic("more tags than fields")
+	}
+	return &Struct{fields: fields, tags: tags}
+}
+
+// NumFields returns the number of fields in the struct (including blank and anonymous fields).
+func (s *Struct) NumFields() int { return len(s.fields) }
+
+// Field returns the i'th field for 0 <= i < NumFields().
+func (s *Struct) Field(i int) *Var { return s.fields[i] }
+
+// Tag returns the i'th field tag for 0 <= i < NumFields().
+func (s *Struct) Tag(i int) string {
+	if i < len(s.tags) {
+		return s.tags[i]
+	}
+	return ""
+}
+
+// A Pointer represents a pointer type.
+type Pointer struct {
+	base Type // element type
+}
+
+// NewPointer returns a new pointer type for the given element (base) type.
+func NewPointer(elem Type) *Pointer { return &Pointer{base: elem} }
+
+// Elem returns the element type for the given pointer p.
+func (p *Pointer) Elem() Type { return p.base }
+
+// A Tuple represents an ordered list of variables; a nil *Tuple is a valid (empty) tuple.
+// Tuples are used as components of signatures and to represent the type of multiple
+// assignments; they are not first class types of Go.
+type Tuple struct {
+	vars []*Var
+}
+
+// NewTuple returns a new tuple for the given variables.
+func NewTuple(x ...*Var) *Tuple {
+	if len(x) > 0 {
+		return &Tuple{x}
+	}
+	return nil
+}
+
+// Len returns the number variables of tuple t.
+func (t *Tuple) Len() int {
+	if t != nil {
+		return len(t.vars)
+	}
+	return 0
+}
+
+// At returns the i'th variable of tuple t.
+func (t *Tuple) At(i int) *Var { return t.vars[i] }
+
+// A Signature represents a (non-builtin) function or method type.
+type Signature struct {
+	// We need to keep the scope in Signature (rather than passing it around
+	// and store it in the Func Object) because when type-checking a function
+	// literal we call the general type checker which returns a general Type.
+	// We then unpack the *Signature and use the scope for the literal body.
+	scope    *Scope // function scope, present for package-local signatures
+	recv     *Var   // nil if not a method
+	params   *Tuple // (incoming) parameters from left to right; or nil
+	results  *Tuple // (outgoing) results from left to right; or nil
+	variadic bool   // true if the last parameter's type is of the form ...T (or string, for append built-in only)
+}
+
+// NewSignature returns a new function type for the given receiver, parameters,
+// and results, either of which may be nil. If variadic is set, the function
+// is variadic, it must have at least one parameter, and the last parameter
+// must be of unnamed slice type.
+func NewSignature(recv *Var, params, results *Tuple, variadic bool) *Signature {
+	if variadic {
+		n := params.Len()
+		if n == 0 {
+			panic("types.NewSignature: variadic function must have at least one parameter")
+		}
+		if _, ok := params.At(n - 1).typ.(*Slice); !ok {
+			panic("types.NewSignature: variadic parameter must be of unnamed slice type")
+		}
+	}
+	return &Signature{nil, recv, params, results, variadic}
+}
+
+// Recv returns the receiver of signature s (if a method), or nil if a
+// function.
+//
+// For an abstract method, Recv returns the enclosing interface either
+// as a *Named or an *Interface.  Due to embedding, an interface may
+// contain methods whose receiver type is a different interface.
+func (s *Signature) Recv() *Var { return s.recv }
+
+// Params returns the parameters of signature s, or nil.
+func (s *Signature) Params() *Tuple { return s.params }
+
+// Results returns the results of signature s, or nil.
+func (s *Signature) Results() *Tuple { return s.results }
+
+// Variadic reports whether the signature s is variadic.
+func (s *Signature) Variadic() bool { return s.variadic }
+
+// An Interface represents an interface type.
+type Interface struct {
+	methods   []*Func  // ordered list of explicitly declared methods
+	embeddeds []*Named // ordered list of explicitly embedded types
+
+	allMethods []*Func // ordered list of methods declared with or embedded in this interface (TODO(gri): replace with mset)
+}
+
+// NewInterface returns a new interface for the given methods and embedded types.
+func NewInterface(methods []*Func, embeddeds []*Named) *Interface {
+	typ := new(Interface)
+
+	var mset objset
+	for _, m := range methods {
+		if mset.insert(m) != nil {
+			panic("multiple methods with the same name")
+		}
+		// set receiver
+		// TODO(gri) Ideally, we should use a named type here instead of
+		// typ, for less verbose printing of interface method signatures.
+		m.typ.(*Signature).recv = NewVar(m.pos, m.pkg, "", typ)
+	}
+	sort.Sort(byUniqueMethodName(methods))
+
+	if embeddeds == nil {
+		sort.Sort(byUniqueTypeName(embeddeds))
+	}
+
+	typ.methods = methods
+	typ.embeddeds = embeddeds
+	return typ
+}
+
+// NumExplicitMethods returns the number of explicitly declared methods of interface t.
+func (t *Interface) NumExplicitMethods() int { return len(t.methods) }
+
+// ExplicitMethod returns the i'th explicitly declared method of interface t for 0 <= i < t.NumExplicitMethods().
+// The methods are ordered by their unique Id.
+func (t *Interface) ExplicitMethod(i int) *Func { return t.methods[i] }
+
+// NumEmbeddeds returns the number of embedded types in interface t.
+func (t *Interface) NumEmbeddeds() int { return len(t.embeddeds) }
+
+// Embedded returns the i'th embedded type of interface t for 0 <= i < t.NumEmbeddeds().
+// The types are ordered by the corresponding TypeName's unique Id.
+func (t *Interface) Embedded(i int) *Named { return t.embeddeds[i] }
+
+// NumMethods returns the total number of methods of interface t.
+func (t *Interface) NumMethods() int { return len(t.allMethods) }
+
+// Method returns the i'th method of interface t for 0 <= i < t.NumMethods().
+// The methods are ordered by their unique Id.
+func (t *Interface) Method(i int) *Func { return t.allMethods[i] }
+
+// Empty returns true if t is the empty interface.
+func (t *Interface) Empty() bool { return len(t.allMethods) == 0 }
+
+// Complete computes the interface's method set. It must be called by users of
+// NewInterface after the interface's embedded types are fully defined and
+// before using the interface type in any way other than to form other types.
+// Complete returns the receiver.
+func (t *Interface) Complete() *Interface {
+	if t.allMethods != nil {
+		return t
+	}
+
+	var allMethods []*Func
+	if t.embeddeds == nil {
+		if t.methods == nil {
+			allMethods = make([]*Func, 0, 1)
+		} else {
+			allMethods = t.methods
+		}
+	} else {
+		allMethods = append(allMethods, t.methods...)
+		for _, et := range t.embeddeds {
+			it := et.Underlying().(*Interface)
+			it.Complete()
+			for _, tm := range it.allMethods {
+				// Make a copy of the method and adjust its receiver type.
+				newm := *tm
+				newmtyp := *tm.typ.(*Signature)
+				newm.typ = &newmtyp
+				newmtyp.recv = NewVar(newm.pos, newm.pkg, "", t)
+				allMethods = append(allMethods, &newm)
+			}
+		}
+		sort.Sort(byUniqueMethodName(allMethods))
+	}
+	t.allMethods = allMethods
+
+	return t
+}
+
+// A Map represents a map type.
+type Map struct {
+	key, elem Type
+}
+
+// NewMap returns a new map for the given key and element types.
+func NewMap(key, elem Type) *Map {
+	return &Map{key, elem}
+}
+
+// Key returns the key type of map m.
+func (m *Map) Key() Type { return m.key }
+
+// Elem returns the element type of map m.
+func (m *Map) Elem() Type { return m.elem }
+
+// A Chan represents a channel type.
+type Chan struct {
+	dir  ChanDir
+	elem Type
+}
+
+// A ChanDir value indicates a channel direction.
+type ChanDir int
+
+// The direction of a channel is indicated by one of the following constants.
+const (
+	SendRecv ChanDir = iota
+	SendOnly
+	RecvOnly
+)
+
+// NewChan returns a new channel type for the given direction and element type.
+func NewChan(dir ChanDir, elem Type) *Chan {
+	return &Chan{dir, elem}
+}
+
+// Dir returns the direction of channel c.
+func (c *Chan) Dir() ChanDir { return c.dir }
+
+// Elem returns the element type of channel c.
+func (c *Chan) Elem() Type { return c.elem }
+
+// A Named represents a named type.
+type Named struct {
+	obj        *TypeName // corresponding declared object
+	underlying Type      // possibly a *Named during setup; never a *Named once set up completely
+	methods    []*Func   // methods declared for this type (not the method set of this type)
+}
+
+// NewNamed returns a new named type for the given type name, underlying type, and associated methods.
+// The underlying type must not be a *Named.
+func NewNamed(obj *TypeName, underlying Type, methods []*Func) *Named {
+	if _, ok := underlying.(*Named); ok {
+		panic("types.NewNamed: underlying type must not be *Named")
+	}
+	typ := &Named{obj: obj, underlying: underlying, methods: methods}
+	if obj.typ == nil {
+		obj.typ = typ
+	}
+	return typ
+}
+
+// TypeName returns the type name for the named type t.
+func (t *Named) Obj() *TypeName { return t.obj }
+
+// NumMethods returns the number of explicit methods whose receiver is named type t.
+func (t *Named) NumMethods() int { return len(t.methods) }
+
+// Method returns the i'th method of named type t for 0 <= i < t.NumMethods().
+func (t *Named) Method(i int) *Func { return t.methods[i] }
+
+// SetUnderlying sets the underlying type and marks t as complete.
+// TODO(gri) determine if there's a better solution rather than providing this function
+func (t *Named) SetUnderlying(underlying Type) {
+	if underlying == nil {
+		panic("types.Named.SetUnderlying: underlying type must not be nil")
+	}
+	if _, ok := underlying.(*Named); ok {
+		panic("types.Named.SetUnderlying: underlying type must not be *Named")
+	}
+	t.underlying = underlying
+}
+
+// AddMethod adds method m unless it is already in the method list.
+// TODO(gri) find a better solution instead of providing this function
+func (t *Named) AddMethod(m *Func) {
+	if i, _ := lookupMethod(t.methods, m.pkg, m.name); i < 0 {
+		t.methods = append(t.methods, m)
+	}
+}
+
+// Implementations for Type methods.
+
+func (t *Basic) Underlying() Type     { return t }
+func (t *Array) Underlying() Type     { return t }
+func (t *Slice) Underlying() Type     { return t }
+func (t *Struct) Underlying() Type    { return t }
+func (t *Pointer) Underlying() Type   { return t }
+func (t *Tuple) Underlying() Type     { return t }
+func (t *Signature) Underlying() Type { return t }
+func (t *Interface) Underlying() Type { return t }
+func (t *Map) Underlying() Type       { return t }
+func (t *Chan) Underlying() Type      { return t }
+func (t *Named) Underlying() Type     { return t.underlying }
+
+func (t *Basic) String() string     { return TypeString(t, nil) }
+func (t *Array) String() string     { return TypeString(t, nil) }
+func (t *Slice) String() string     { return TypeString(t, nil) }
+func (t *Struct) String() string    { return TypeString(t, nil) }
+func (t *Pointer) String() string   { return TypeString(t, nil) }
+func (t *Tuple) String() string     { return TypeString(t, nil) }
+func (t *Signature) String() string { return TypeString(t, nil) }
+func (t *Interface) String() string { return TypeString(t, nil) }
+func (t *Map) String() string       { return TypeString(t, nil) }
+func (t *Chan) String() string      { return TypeString(t, nil) }
+func (t *Named) String() string     { return TypeString(t, nil) }

Godeps/_workspace/src/golang.org/x/tools/go/types/typestring.go

@@ -0,0 +1,292 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements printing of types.
+
+package types
+
+import (
+	"bytes"
+	"fmt"
+)
+
+// A Qualifier controls how named package-level objects are printed in
+// calls to TypeString, ObjectString, and SelectionString.
+//
+// These three formatting routines call the Qualifier for each
+// package-level object O, and if the Qualifier returns a non-empty
+// string p, the object is printed in the form p.O.
+// If it returns an empty string, only the object name O is printed.
+//
+// Using a nil Qualifier is equivalent to using (*Package).Path: the
+// object is qualified by the import path, e.g., "encoding/json.Marshal".
+//
+type Qualifier func(*Package) string
+
+// RelativeTo(pkg) returns a Qualifier that fully qualifies members of
+// all packages other than pkg.
+func RelativeTo(pkg *Package) Qualifier {
+	if pkg == nil {
+		return nil
+	}
+	return func(other *Package) string {
+		if pkg == other {
+			return "" // same package; unqualified
+		}
+		return other.Path()
+	}
+}
+
+// If GcCompatibilityMode is set, printing of types is modified
+// to match the representation of some types in the gc compiler:
+//
+//	- byte and rune lose their alias name and simply stand for
+//	  uint8 and int32 respectively
+//	- embedded interfaces get flattened (the embedding info is lost,
+//	  and certain recursive interface types cannot be printed anymore)
+//
+// This makes it easier to compare packages computed with the type-
+// checker vs packages imported from gc export data.
+//
+// Caution: This flag affects all uses of WriteType, globally.
+// It is only provided for testing in conjunction with
+// gc-generated data. It may be removed at any time.
+var GcCompatibilityMode bool
+
+// TypeString returns the string representation of typ.
+// The Qualifier controls the printing of
+// package-level objects, and may be nil.
+func TypeString(typ Type, qf Qualifier) string {
+	var buf bytes.Buffer
+	WriteType(&buf, typ, qf)
+	return buf.String()
+}
+
+// WriteType writes the string representation of typ to buf.
+// The Qualifier controls the printing of
+// package-level objects, and may be nil.
+func WriteType(buf *bytes.Buffer, typ Type, qf Qualifier) {
+	writeType(buf, typ, qf, make([]Type, 8))
+}
+
+func writeType(buf *bytes.Buffer, typ Type, qf Qualifier, visited []Type) {
+	// Theoretically, this is a quadratic lookup algorithm, but in
+	// practice deeply nested composite types with unnamed component
+	// types are uncommon. This code is likely more efficient than
+	// using a map.
+	for _, t := range visited {
+		if t == typ {
+			fmt.Fprintf(buf, "○%T", typ) // cycle to typ
+			return
+		}
+	}
+	visited = append(visited, typ)
+
+	switch t := typ.(type) {
+	case nil:
+		buf.WriteString("<nil>")
+
+	case *Basic:
+		if t.kind == UnsafePointer {
+			buf.WriteString("unsafe.")
+		}
+		if GcCompatibilityMode {
+			// forget the alias names
+			switch t.kind {
+			case Byte:
+				t = Typ[Uint8]
+			case Rune:
+				t = Typ[Int32]
+			}
+		}
+		buf.WriteString(t.name)
+
+	case *Array:
+		fmt.Fprintf(buf, "[%d]", t.len)
+		writeType(buf, t.elem, qf, visited)
+
+	case *Slice:
+		buf.WriteString("[]")
+		writeType(buf, t.elem, qf, visited)
+
+	case *Struct:
+		buf.WriteString("struct{")
+		for i, f := range t.fields {
+			if i > 0 {
+				buf.WriteString("; ")
+			}
+			if !f.anonymous {
+				buf.WriteString(f.name)
+				buf.WriteByte(' ')
+			}
+			writeType(buf, f.typ, qf, visited)
+			if tag := t.Tag(i); tag != "" {
+				fmt.Fprintf(buf, " %q", tag)
+			}
+		}
+		buf.WriteByte('}')
+
+	case *Pointer:
+		buf.WriteByte('*')
+		writeType(buf, t.base, qf, visited)
+
+	case *Tuple:
+		writeTuple(buf, t, false, qf, visited)
+
+	case *Signature:
+		buf.WriteString("func")
+		writeSignature(buf, t, qf, visited)
+
+	case *Interface:
+		// We write the source-level methods and embedded types rather
+		// than the actual method set since resolved method signatures
+		// may have non-printable cycles if parameters have anonymous
+		// interface types that (directly or indirectly) embed the
+		// current interface. For instance, consider the result type
+		// of m:
+		//
+		//     type T interface{
+		//         m() interface{ T }
+		//     }
+		//
+		buf.WriteString("interface{")
+		if GcCompatibilityMode {
+			// print flattened interface
+			// (useful to compare against gc-generated interfaces)
+			for i, m := range t.allMethods {
+				if i > 0 {
+					buf.WriteString("; ")
+				}
+				buf.WriteString(m.name)
+				writeSignature(buf, m.typ.(*Signature), qf, visited)
+			}
+		} else {
+			// print explicit interface methods and embedded types
+			for i, m := range t.methods {
+				if i > 0 {
+					buf.WriteString("; ")
+				}
+				buf.WriteString(m.name)
+				writeSignature(buf, m.typ.(*Signature), qf, visited)
+			}
+			for i, typ := range t.embeddeds {
+				if i > 0 || len(t.methods) > 0 {
+					buf.WriteString("; ")
+				}
+				writeType(buf, typ, qf, visited)
+			}
+		}
+		buf.WriteByte('}')
+
+	case *Map:
+		buf.WriteString("map[")
+		writeType(buf, t.key, qf, visited)
+		buf.WriteByte(']')
+		writeType(buf, t.elem, qf, visited)
+
+	case *Chan:
+		var s string
+		var parens bool
+		switch t.dir {
+		case SendRecv:
+			s = "chan "
+			// chan (<-chan T) requires parentheses
+			if c, _ := t.elem.(*Chan); c != nil && c.dir == RecvOnly {
+				parens = true
+			}
+		case SendOnly:
+			s = "chan<- "
+		case RecvOnly:
+			s = "<-chan "
+		default:
+			panic("unreachable")
+		}
+		buf.WriteString(s)
+		if parens {
+			buf.WriteByte('(')
+		}
+		writeType(buf, t.elem, qf, visited)
+		if parens {
+			buf.WriteByte(')')
+		}
+
+	case *Named:
+		s := "<Named w/o object>"
+		if obj := t.obj; obj != nil {
+			if obj.pkg != nil {
+				writePackage(buf, obj.pkg, qf)
+			}
+			// TODO(gri): function-local named types should be displayed
+			// differently from named types at package level to avoid
+			// ambiguity.
+			s = obj.name
+		}
+		buf.WriteString(s)
+
+	default:
+		// For externally defined implementations of Type.
+		buf.WriteString(t.String())
+	}
+}
+
+func writeTuple(buf *bytes.Buffer, tup *Tuple, variadic bool, qf Qualifier, visited []Type) {
+	buf.WriteByte('(')
+	if tup != nil {
+		for i, v := range tup.vars {
+			if i > 0 {
+				buf.WriteString(", ")
+			}
+			if v.name != "" {
+				buf.WriteString(v.name)
+				buf.WriteByte(' ')
+			}
+			typ := v.typ
+			if variadic && i == len(tup.vars)-1 {
+				if s, ok := typ.(*Slice); ok {
+					buf.WriteString("...")
+					typ = s.elem
+				} else {
+					// special case:
+					// append(s, "foo"...) leads to signature func([]byte, string...)
+					if t, ok := typ.Underlying().(*Basic); !ok || t.kind != String {
+						panic("internal error: string type expected")
+					}
+					writeType(buf, typ, qf, visited)
+					buf.WriteString("...")
+					continue
+				}
+			}
+			writeType(buf, typ, qf, visited)
+		}
+	}
+	buf.WriteByte(')')
+}
+
+// WriteSignature writes the representation of the signature sig to buf,
+// without a leading "func" keyword.
+// The Qualifier controls the printing of
+// package-level objects, and may be nil.
+func WriteSignature(buf *bytes.Buffer, sig *Signature, qf Qualifier) {
+	writeSignature(buf, sig, qf, make([]Type, 8))
+}
+
+func writeSignature(buf *bytes.Buffer, sig *Signature, qf Qualifier, visited []Type) {
+	writeTuple(buf, sig.params, sig.variadic, qf, visited)
+
+	n := sig.results.Len()
+	if n == 0 {
+		// no result
+		return
+	}
+
+	buf.WriteByte(' ')
+	if n == 1 && sig.results.vars[0].name == "" {
+		// single unnamed result
+		writeType(buf, sig.results.vars[0].typ, qf, visited)
+		return
+	}
+
+	// multiple or named result(s)
+	writeTuple(buf, sig.results, false, qf, visited)
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/typestring_test.go

@@ -0,0 +1,166 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package types_test
+
+import (
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"testing"
+
+	_ "golang.org/x/tools/go/gcimporter"
+	. "golang.org/x/tools/go/types"
+)
+
+const filename = "<src>"
+
+func makePkg(t *testing.T, src string) (*Package, error) {
+	fset := token.NewFileSet()
+	file, err := parser.ParseFile(fset, filename, src, parser.DeclarationErrors)
+	if err != nil {
+		return nil, err
+	}
+	// use the package name as package path
+	return Check(file.Name.Name, fset, []*ast.File{file})
+}
+
+type testEntry struct {
+	src, str string
+}
+
+// dup returns a testEntry where both src and str are the same.
+func dup(s string) testEntry {
+	return testEntry{s, s}
+}
+
+// types that don't depend on any other type declarations
+var independentTestTypes = []testEntry{
+	// basic types
+	dup("int"),
+	dup("float32"),
+	dup("string"),
+
+	// arrays
+	dup("[10]int"),
+
+	// slices
+	dup("[]int"),
+	dup("[][]int"),
+
+	// structs
+	dup("struct{}"),
+	dup("struct{x int}"),
+	{`struct {
+		x, y int
+		z float32 "foo"
+	}`, `struct{x int; y int; z float32 "foo"}`},
+	{`struct {
+		string
+		elems []complex128
+	}`, `struct{string; elems []complex128}`},
+
+	// pointers
+	dup("*int"),
+	dup("***struct{}"),
+	dup("*struct{a int; b float32}"),
+
+	// functions
+	dup("func()"),
+	dup("func(x int)"),
+	{"func(x, y int)", "func(x int, y int)"},
+	{"func(x, y int, z string)", "func(x int, y int, z string)"},
+	dup("func(int)"),
+	{"func(int, string, byte)", "func(int, string, byte)"},
+
+	dup("func() int"),
+	{"func() (string)", "func() string"},
+	dup("func() (u int)"),
+	{"func() (u, v int, w string)", "func() (u int, v int, w string)"},
+
+	dup("func(int) string"),
+	dup("func(x int) string"),
+	dup("func(x int) (u string)"),
+	{"func(x, y int) (u string)", "func(x int, y int) (u string)"},
+
+	dup("func(...int) string"),
+	dup("func(x ...int) string"),
+	dup("func(x ...int) (u string)"),
+	{"func(x, y ...int) (u string)", "func(x int, y ...int) (u string)"},
+
+	// interfaces
+	dup("interface{}"),
+	dup("interface{m()}"),
+	dup(`interface{String() string; m(int) float32}`),
+
+	// maps
+	dup("map[string]int"),
+	{"map[struct{x, y int}][]byte", "map[struct{x int; y int}][]byte"},
+
+	// channels
+	dup("chan<- chan int"),
+	dup("chan<- <-chan int"),
+	dup("<-chan <-chan int"),
+	dup("chan (<-chan int)"),
+	dup("chan<- func()"),
+	dup("<-chan []func() int"),
+}
+
+// types that depend on other type declarations (src in TestTypes)
+var dependentTestTypes = []testEntry{
+	// interfaces
+	dup(`interface{io.Reader; io.Writer}`),
+	dup(`interface{m() int; io.Writer}`),
+	{`interface{m() interface{T}}`, `interface{m() interface{p.T}}`},
+}
+
+func TestTypeString(t *testing.T) {
+	skipSpecialPlatforms(t)
+
+	var tests []testEntry
+	tests = append(tests, independentTestTypes...)
+	tests = append(tests, dependentTestTypes...)
+
+	for _, test := range tests {
+		src := `package p; import "io"; type _ io.Writer; type T ` + test.src
+		pkg, err := makePkg(t, src)
+		if err != nil {
+			t.Errorf("%s: %s", src, err)
+			continue
+		}
+		typ := pkg.Scope().Lookup("T").Type().Underlying()
+		if got := typ.String(); got != test.str {
+			t.Errorf("%s: got %s, want %s", test.src, got, test.str)
+		}
+	}
+}
+
+func TestQualifiedTypeString(t *testing.T) {
+	p, _ := pkgFor("p.go", "package p; type T int", nil)
+	q, _ := pkgFor("q.go", "package q", nil)
+
+	pT := p.Scope().Lookup("T").Type()
+	for _, test := range []struct {
+		typ  Type
+		this *Package
+		want string
+	}{
+		{pT, nil, "p.T"},
+		{pT, p, "T"},
+		{pT, q, "p.T"},
+		{NewPointer(pT), p, "*T"},
+		{NewPointer(pT), q, "*p.T"},
+	} {
+		qualifier := func(pkg *Package) string {
+			if pkg != test.this {
+				return pkg.Name()
+			}
+			return ""
+		}
+		if got := TypeString(test.typ, qualifier); got != test.want {
+			t.Errorf("TypeString(%s, %s) = %s, want %s",
+				test.this, test.typ, got, test.want)
+		}
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/typeutil/example_test.go

@@ -0,0 +1,68 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package typeutil_test
+
+import (
+	"fmt"
+	"sort"
+
+	"go/ast"
+	"go/parser"
+	"go/token"
+
+	"golang.org/x/tools/go/types"
+	"golang.org/x/tools/go/types/typeutil"
+)
+
+func ExampleMap() {
+	const source = `package P
+
+var X []string
+var Y []string
+
+const p, q = 1.0, 2.0
+
+func f(offset int32) (value byte, ok bool)
+func g(rune) (uint8, bool)
+`
+
+	// Parse and type-check the package.
+	fset := token.NewFileSet()
+	f, err := parser.ParseFile(fset, "P.go", source, 0)
+	if err != nil {
+		panic(err)
+	}
+	pkg, err := new(types.Config).Check("P", fset, []*ast.File{f}, nil)
+	if err != nil {
+		panic(err)
+	}
+
+	scope := pkg.Scope()
+
+	// Group names of package-level objects by their type.
+	var namesByType typeutil.Map // value is []string
+	for _, name := range scope.Names() {
+		T := scope.Lookup(name).Type()
+
+		names, _ := namesByType.At(T).([]string)
+		names = append(names, name)
+		namesByType.Set(T, names)
+	}
+
+	// Format, sort, and print the map entries.
+	var lines []string
+	namesByType.Iterate(func(T types.Type, names interface{}) {
+		lines = append(lines, fmt.Sprintf("%s   %s", names, T))
+	})
+	sort.Strings(lines)
+	for _, line := range lines {
+		fmt.Println(line)
+	}
+
+	// Output:
+	// [X Y]   []string
+	// [f g]   func(offset int32) (value byte, ok bool)
+	// [p q]   untyped float
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/typeutil/imports.go

@@ -0,0 +1,31 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package typeutil
+
+import "golang.org/x/tools/go/types"
+
+// Dependencies returns all dependencies of the specified packages.
+//
+// Dependent packages appear in topological order: if package P imports
+// package Q, Q appears earlier than P in the result.
+// The algorithm follows import statements in the order they
+// appear in the source code, so the result is a total order.
+//
+func Dependencies(pkgs ...*types.Package) []*types.Package {
+	var result []*types.Package
+	seen := make(map[*types.Package]bool)
+	var visit func(pkgs []*types.Package)
+	visit = func(pkgs []*types.Package) {
+		for _, p := range pkgs {
+			if !seen[p] {
+				seen[p] = true
+				visit(p.Imports())
+				result = append(result, p)
+			}
+		}
+	}
+	visit(pkgs)
+	return result
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/typeutil/imports_test.go

@@ -0,0 +1,79 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package typeutil_test
+
+import (
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"testing"
+
+	"golang.org/x/tools/go/types"
+	"golang.org/x/tools/go/types/typeutil"
+)
+
+func TestDependencies(t *testing.T) {
+	packages := make(map[string]*types.Package)
+	conf := types.Config{
+		Packages: packages,
+		Import: func(_ map[string]*types.Package, path string) (*types.Package, error) {
+			return packages[path], nil
+		},
+	}
+	fset := token.NewFileSet()
+
+	// All edges go to the right.
+	//  /--D--B--A
+	// F    \_C_/
+	//  \__E_/
+	for i, content := range []string{
+		`package A`,
+		`package C; import (_ "A")`,
+		`package B; import (_ "A")`,
+		`package E; import (_ "C")`,
+		`package D; import (_ "B"; _ "C")`,
+		`package F; import (_ "D"; _ "E")`,
+	} {
+		f, err := parser.ParseFile(fset, fmt.Sprintf("%d.go", i), content, 0)
+		if err != nil {
+			t.Fatal(err)
+		}
+		pkg, err := conf.Check(f.Name.Name, fset, []*ast.File{f}, nil)
+		if err != nil {
+			t.Fatal(err)
+		}
+		packages[pkg.Path()] = pkg
+	}
+
+	for _, test := range []struct {
+		roots, want string
+	}{
+		{"A", "A"},
+		{"B", "AB"},
+		{"C", "AC"},
+		{"D", "ABCD"},
+		{"E", "ACE"},
+		{"F", "ABCDEF"},
+
+		{"BE", "ABCE"},
+		{"EB", "ACEB"},
+		{"DE", "ABCDE"},
+		{"ED", "ACEBD"},
+		{"EF", "ACEBDF"},
+	} {
+		var pkgs []*types.Package
+		for _, r := range test.roots {
+			pkgs = append(pkgs, conf.Packages[string(r)])
+		}
+		var got string
+		for _, p := range typeutil.Dependencies(pkgs...) {
+			got += p.Path()
+		}
+		if got != test.want {
+			t.Errorf("Dependencies(%q) = %q, want %q", test.roots, got, test.want)
+		}
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/typeutil/map.go

@@ -0,0 +1,314 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package typeutil defines various utilities for types, such as Map,
+// a mapping from types.Type to interface{} values.
+package typeutil
+
+import (
+	"bytes"
+	"fmt"
+	"reflect"
+
+	"golang.org/x/tools/go/types"
+)
+
+// Map is a hash-table-based mapping from types (types.Type) to
+// arbitrary interface{} values.  The concrete types that implement
+// the Type interface are pointers.  Since they are not canonicalized,
+// == cannot be used to check for equivalence, and thus we cannot
+// simply use a Go map.
+//
+// Just as with map[K]V, a nil *Map is a valid empty map.
+//
+// Not thread-safe.
+//
+type Map struct {
+	hasher Hasher             // shared by many Maps
+	table  map[uint32][]entry // maps hash to bucket; entry.key==nil means unused
+	length int                // number of map entries
+}
+
+// entry is an entry (key/value association) in a hash bucket.
+type entry struct {
+	key   types.Type
+	value interface{}
+}
+
+// SetHasher sets the hasher used by Map.
+//
+// All Hashers are functionally equivalent but contain internal state
+// used to cache the results of hashing previously seen types.
+//
+// A single Hasher created by MakeHasher() may be shared among many
+// Maps.  This is recommended if the instances have many keys in
+// common, as it will amortize the cost of hash computation.
+//
+// A Hasher may grow without bound as new types are seen.  Even when a
+// type is deleted from the map, the Hasher never shrinks, since other
+// types in the map may reference the deleted type indirectly.
+//
+// Hashers are not thread-safe, and read-only operations such as
+// Map.Lookup require updates to the hasher, so a full Mutex lock (not a
+// read-lock) is require around all Map operations if a shared
+// hasher is accessed from multiple threads.
+//
+// If SetHasher is not called, the Map will create a private hasher at
+// the first call to Insert.
+//
+func (m *Map) SetHasher(hasher Hasher) {
+	m.hasher = hasher
+}
+
+// Delete removes the entry with the given key, if any.
+// It returns true if the entry was found.
+//
+func (m *Map) Delete(key types.Type) bool {
+	if m != nil && m.table != nil {
+		hash := m.hasher.Hash(key)
+		bucket := m.table[hash]
+		for i, e := range bucket {
+			if e.key != nil && types.Identical(key, e.key) {
+				// We can't compact the bucket as it
+				// would disturb iterators.
+				bucket[i] = entry{}
+				m.length--
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// At returns the map entry for the given key.
+// The result is nil if the entry is not present.
+//
+func (m *Map) At(key types.Type) interface{} {
+	if m != nil && m.table != nil {
+		for _, e := range m.table[m.hasher.Hash(key)] {
+			if e.key != nil && types.Identical(key, e.key) {
+				return e.value
+			}
+		}
+	}
+	return nil
+}
+
+// Set sets the map entry for key to val,
+// and returns the previous entry, if any.
+func (m *Map) Set(key types.Type, value interface{}) (prev interface{}) {
+	if m.table != nil {
+		hash := m.hasher.Hash(key)
+		bucket := m.table[hash]
+		var hole *entry
+		for i, e := range bucket {
+			if e.key == nil {
+				hole = &bucket[i]
+			} else if types.Identical(key, e.key) {
+				prev = e.value
+				bucket[i].value = value
+				return
+			}
+		}
+
+		if hole != nil {
+			*hole = entry{key, value} // overwrite deleted entry
+		} else {
+			m.table[hash] = append(bucket, entry{key, value})
+		}
+	} else {
+		if m.hasher.memo == nil {
+			m.hasher = MakeHasher()
+		}
+		hash := m.hasher.Hash(key)
+		m.table = map[uint32][]entry{hash: {entry{key, value}}}
+	}
+
+	m.length++
+	return
+}
+
+// Len returns the number of map entries.
+func (m *Map) Len() int {
+	if m != nil {
+		return m.length
+	}
+	return 0
+}
+
+// Iterate calls function f on each entry in the map in unspecified order.
+//
+// If f should mutate the map, Iterate provides the same guarantees as
+// Go maps: if f deletes a map entry that Iterate has not yet reached,
+// f will not be invoked for it, but if f inserts a map entry that
+// Iterate has not yet reached, whether or not f will be invoked for
+// it is unspecified.
+//
+func (m *Map) Iterate(f func(key types.Type, value interface{})) {
+	if m != nil {
+		for _, bucket := range m.table {
+			for _, e := range bucket {
+				if e.key != nil {
+					f(e.key, e.value)
+				}
+			}
+		}
+	}
+}
+
+// Keys returns a new slice containing the set of map keys.
+// The order is unspecified.
+func (m *Map) Keys() []types.Type {
+	keys := make([]types.Type, 0, m.Len())
+	m.Iterate(func(key types.Type, _ interface{}) {
+		keys = append(keys, key)
+	})
+	return keys
+}
+
+func (m *Map) toString(values bool) string {
+	if m == nil {
+		return "{}"
+	}
+	var buf bytes.Buffer
+	fmt.Fprint(&buf, "{")
+	sep := ""
+	m.Iterate(func(key types.Type, value interface{}) {
+		fmt.Fprint(&buf, sep)
+		sep = ", "
+		fmt.Fprint(&buf, key)
+		if values {
+			fmt.Fprintf(&buf, ": %q", value)
+		}
+	})
+	fmt.Fprint(&buf, "}")
+	return buf.String()
+}
+
+// String returns a string representation of the map's entries.
+// Values are printed using fmt.Sprintf("%v", v).
+// Order is unspecified.
+//
+func (m *Map) String() string {
+	return m.toString(true)
+}
+
+// KeysString returns a string representation of the map's key set.
+// Order is unspecified.
+//
+func (m *Map) KeysString() string {
+	return m.toString(false)
+}
+
+////////////////////////////////////////////////////////////////////////
+// Hasher
+
+// A Hasher maps each type to its hash value.
+// For efficiency, a hasher uses memoization; thus its memory
+// footprint grows monotonically over time.
+// Hashers are not thread-safe.
+// Hashers have reference semantics.
+// Call MakeHasher to create a Hasher.
+type Hasher struct {
+	memo map[types.Type]uint32
+}
+
+// MakeHasher returns a new Hasher instance.
+func MakeHasher() Hasher {
+	return Hasher{make(map[types.Type]uint32)}
+}
+
+// Hash computes a hash value for the given type t such that
+// Identical(t, t') => Hash(t) == Hash(t').
+func (h Hasher) Hash(t types.Type) uint32 {
+	hash, ok := h.memo[t]
+	if !ok {
+		hash = h.hashFor(t)
+		h.memo[t] = hash
+	}
+	return hash
+}
+
+// hashString computes the Fowler–Noll–Vo hash of s.
+func hashString(s string) uint32 {
+	var h uint32
+	for i := 0; i < len(s); i++ {
+		h ^= uint32(s[i])
+		h *= 16777619
+	}
+	return h
+}
+
+// hashFor computes the hash of t.
+func (h Hasher) hashFor(t types.Type) uint32 {
+	// See Identical for rationale.
+	switch t := t.(type) {
+	case *types.Basic:
+		return uint32(t.Kind())
+
+	case *types.Array:
+		return 9043 + 2*uint32(t.Len()) + 3*h.Hash(t.Elem())
+
+	case *types.Slice:
+		return 9049 + 2*h.Hash(t.Elem())
+
+	case *types.Struct:
+		var hash uint32 = 9059
+		for i, n := 0, t.NumFields(); i < n; i++ {
+			f := t.Field(i)
+			if f.Anonymous() {
+				hash += 8861
+			}
+			hash += hashString(t.Tag(i))
+			hash += hashString(f.Name()) // (ignore f.Pkg)
+			hash += h.Hash(f.Type())
+		}
+		return hash
+
+	case *types.Pointer:
+		return 9067 + 2*h.Hash(t.Elem())
+
+	case *types.Signature:
+		var hash uint32 = 9091
+		if t.Variadic() {
+			hash *= 8863
+		}
+		return hash + 3*h.hashTuple(t.Params()) + 5*h.hashTuple(t.Results())
+
+	case *types.Interface:
+		var hash uint32 = 9103
+		for i, n := 0, t.NumMethods(); i < n; i++ {
+			// See go/types.identicalMethods for rationale.
+			// Method order is not significant.
+			// Ignore m.Pkg().
+			m := t.Method(i)
+			hash += 3*hashString(m.Name()) + 5*h.Hash(m.Type())
+		}
+		return hash
+
+	case *types.Map:
+		return 9109 + 2*h.Hash(t.Key()) + 3*h.Hash(t.Elem())
+
+	case *types.Chan:
+		return 9127 + 2*uint32(t.Dir()) + 3*h.Hash(t.Elem())
+
+	case *types.Named:
+		// Not safe with a copying GC; objects may move.
+		return uint32(reflect.ValueOf(t.Obj()).Pointer())
+
+	case *types.Tuple:
+		return h.hashTuple(t)
+	}
+	panic(t)
+}
+
+func (h Hasher) hashTuple(tuple *types.Tuple) uint32 {
+	// See go/types.identicalTypes for rationale.
+	n := tuple.Len()
+	var hash uint32 = 9137 + 2*uint32(n)
+	for i := 0; i < n; i++ {
+		hash += 3 * h.Hash(tuple.At(i).Type())
+	}
+	return hash
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/typeutil/map_test.go

@@ -0,0 +1,174 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package typeutil_test
+
+// TODO(adonovan):
+// - test use of explicit hasher across two maps.
+// - test hashcodes are consistent with equals for a range of types
+//   (e.g. all types generated by type-checking some body of real code).
+
+import (
+	"testing"
+
+	"golang.org/x/tools/go/types"
+	"golang.org/x/tools/go/types/typeutil"
+)
+
+var (
+	tStr      = types.Typ[types.String]             // string
+	tPStr1    = types.NewPointer(tStr)              // *string
+	tPStr2    = types.NewPointer(tStr)              // *string, again
+	tInt      = types.Typ[types.Int]                // int
+	tChanInt1 = types.NewChan(types.RecvOnly, tInt) // <-chan int
+	tChanInt2 = types.NewChan(types.RecvOnly, tInt) // <-chan int, again
+)
+
+func checkEqualButNotIdentical(t *testing.T, x, y types.Type, comment string) {
+	if !types.Identical(x, y) {
+		t.Errorf("%s: not equal: %s, %s", comment, x, y)
+	}
+	if x == y {
+		t.Errorf("%s: identical: %v, %v", comment, x, y)
+	}
+}
+
+func TestAxioms(t *testing.T) {
+	checkEqualButNotIdentical(t, tPStr1, tPStr2, "tPstr{1,2}")
+	checkEqualButNotIdentical(t, tChanInt1, tChanInt2, "tChanInt{1,2}")
+}
+
+func TestMap(t *testing.T) {
+	var tmap *typeutil.Map
+
+	// All methods but Set are safe on on (*T)(nil).
+	tmap.Len()
+	tmap.At(tPStr1)
+	tmap.Delete(tPStr1)
+	tmap.KeysString()
+	tmap.String()
+
+	tmap = new(typeutil.Map)
+
+	// Length of empty map.
+	if l := tmap.Len(); l != 0 {
+		t.Errorf("Len() on empty Map: got %d, want 0", l)
+	}
+	// At of missing key.
+	if v := tmap.At(tPStr1); v != nil {
+		t.Errorf("At() on empty Map: got %v, want nil", v)
+	}
+	// Deletion of missing key.
+	if tmap.Delete(tPStr1) {
+		t.Errorf("Delete() on empty Map: got true, want false")
+	}
+	// Set of new key.
+	if prev := tmap.Set(tPStr1, "*string"); prev != nil {
+		t.Errorf("Set() on empty Map returned non-nil previous value %s", prev)
+	}
+
+	// Now: {*string: "*string"}
+
+	// Length of non-empty map.
+	if l := tmap.Len(); l != 1 {
+		t.Errorf("Len(): got %d, want 1", l)
+	}
+	// At via insertion key.
+	if v := tmap.At(tPStr1); v != "*string" {
+		t.Errorf("At(): got %q, want \"*string\"", v)
+	}
+	// At via equal key.
+	if v := tmap.At(tPStr2); v != "*string" {
+		t.Errorf("At(): got %q, want \"*string\"", v)
+	}
+	// Iteration over sole entry.
+	tmap.Iterate(func(key types.Type, value interface{}) {
+		if key != tPStr1 {
+			t.Errorf("Iterate: key: got %s, want %s", key, tPStr1)
+		}
+		if want := "*string"; value != want {
+			t.Errorf("Iterate: value: got %s, want %s", value, want)
+		}
+	})
+
+	// Setion with key equal to present one.
+	if prev := tmap.Set(tPStr2, "*string again"); prev != "*string" {
+		t.Errorf("Set() previous value: got %s, want \"*string\"", prev)
+	}
+
+	// Setion of another association.
+	if prev := tmap.Set(tChanInt1, "<-chan int"); prev != nil {
+		t.Errorf("Set() previous value: got %s, want nil", prev)
+	}
+
+	// Now: {*string: "*string again", <-chan int: "<-chan int"}
+
+	want1 := "{*string: \"*string again\", <-chan int: \"<-chan int\"}"
+	want2 := "{<-chan int: \"<-chan int\", *string: \"*string again\"}"
+	if s := tmap.String(); s != want1 && s != want2 {
+		t.Errorf("String(): got %s, want %s", s, want1)
+	}
+
+	want1 = "{*string, <-chan int}"
+	want2 = "{<-chan int, *string}"
+	if s := tmap.KeysString(); s != want1 && s != want2 {
+		t.Errorf("KeysString(): got %s, want %s", s, want1)
+	}
+
+	// Keys().
+	I := types.Identical
+	switch k := tmap.Keys(); {
+	case I(k[0], tChanInt1) && I(k[1], tPStr1): // ok
+	case I(k[1], tChanInt1) && I(k[0], tPStr1): // ok
+	default:
+		t.Errorf("Keys(): got %v, want %s", k, want2)
+	}
+
+	if l := tmap.Len(); l != 2 {
+		t.Errorf("Len(): got %d, want 1", l)
+	}
+	// At via original key.
+	if v := tmap.At(tPStr1); v != "*string again" {
+		t.Errorf("At(): got %q, want \"*string again\"", v)
+	}
+	hamming := 1
+	tmap.Iterate(func(key types.Type, value interface{}) {
+		switch {
+		case I(key, tChanInt1):
+			hamming *= 2 // ok
+		case I(key, tPStr1):
+			hamming *= 3 // ok
+		}
+	})
+	if hamming != 6 {
+		t.Errorf("Iterate: hamming: got %d, want %d", hamming, 6)
+	}
+
+	if v := tmap.At(tChanInt2); v != "<-chan int" {
+		t.Errorf("At(): got %q, want \"<-chan int\"", v)
+	}
+	// Deletion with key equal to present one.
+	if !tmap.Delete(tChanInt2) {
+		t.Errorf("Delete() of existing key: got false, want true")
+	}
+
+	// Now: {*string: "*string again"}
+
+	if l := tmap.Len(); l != 1 {
+		t.Errorf("Len(): got %d, want 1", l)
+	}
+	// Deletion again.
+	if !tmap.Delete(tPStr2) {
+		t.Errorf("Delete() of existing key: got false, want true")
+	}
+
+	// Now: {}
+
+	if l := tmap.Len(); l != 0 {
+		t.Errorf("Len(): got %d, want %d", l, 0)
+	}
+	if s := tmap.String(); s != "{}" {
+		t.Errorf("Len(): got %q, want %q", s, "")
+	}
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/typeutil/methodsetcache.go

@@ -0,0 +1,73 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements a cache of method sets.
+
+package typeutil
+
+import (
+	"sync"
+
+	"golang.org/x/tools/go/types"
+)
+
+// A MethodSetCache records the method set of each type T for which
+// MethodSet(T) is called so that repeat queries are fast.
+// The zero value is a ready-to-use cache instance.
+type MethodSetCache struct {
+	mu     sync.Mutex
+	named  map[*types.Named]struct{ value, pointer *types.MethodSet } // method sets for named N and *N
+	others map[types.Type]*types.MethodSet                            // all other types
+}
+
+// MethodSet returns the method set of type T.  It is thread-safe.
+//
+// If cache is nil, this function is equivalent to types.NewMethodSet(T).
+// Utility functions can thus expose an optional *MethodSetCache
+// parameter to clients that care about performance.
+//
+func (cache *MethodSetCache) MethodSet(T types.Type) *types.MethodSet {
+	if cache == nil {
+		return types.NewMethodSet(T)
+	}
+	cache.mu.Lock()
+	defer cache.mu.Unlock()
+
+	switch T := T.(type) {
+	case *types.Named:
+		return cache.lookupNamed(T).value
+
+	case *types.Pointer:
+		if N, ok := T.Elem().(*types.Named); ok {
+			return cache.lookupNamed(N).pointer
+		}
+	}
+
+	// all other types
+	// (The map uses pointer equivalence, not type identity.)
+	mset := cache.others[T]
+	if mset == nil {
+		mset = types.NewMethodSet(T)
+		if cache.others == nil {
+			cache.others = make(map[types.Type]*types.MethodSet)
+		}
+		cache.others[T] = mset
+	}
+	return mset
+}
+
+func (cache *MethodSetCache) lookupNamed(named *types.Named) struct{ value, pointer *types.MethodSet } {
+	if cache.named == nil {
+		cache.named = make(map[*types.Named]struct{ value, pointer *types.MethodSet })
+	}
+	// Avoid recomputing mset(*T) for each distinct Pointer
+	// instance whose underlying type is a named type.
+	msets, ok := cache.named[named]
+	if !ok {
+		msets.value = types.NewMethodSet(named)
+		msets.pointer = types.NewMethodSet(types.NewPointer(named))
+		cache.named[named] = msets
+	}
+	return msets
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/typeutil/ui.go

@@ -0,0 +1,38 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package typeutil
+
+// This file defines utilities for user interfaces that display types.
+
+import "golang.org/x/tools/go/types"
+
+// IntuitiveMethodSet returns the intuitive method set of a type, T.
+//
+// The result contains MethodSet(T) and additionally, if T is a
+// concrete type, methods belonging to *T if there is no identically
+// named method on T itself.  This corresponds to user intuition about
+// method sets; this function is intended only for user interfaces.
+//
+// The order of the result is as for types.MethodSet(T).
+//
+func IntuitiveMethodSet(T types.Type, msets *MethodSetCache) []*types.Selection {
+	var result []*types.Selection
+	mset := msets.MethodSet(T)
+	if _, ok := T.Underlying().(*types.Interface); ok {
+		for i, n := 0, mset.Len(); i < n; i++ {
+			result = append(result, mset.At(i))
+		}
+	} else {
+		pmset := msets.MethodSet(types.NewPointer(T))
+		for i, n := 0, pmset.Len(); i < n; i++ {
+			meth := pmset.At(i)
+			if m := mset.Lookup(meth.Obj().Pkg(), meth.Obj().Name()); m != nil {
+				meth = m
+			}
+			result = append(result, meth)
+		}
+	}
+	return result
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/typexpr.go

@@ -0,0 +1,713 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements type-checking of identifiers and type expressions.
+
+package types
+
+import (
+	"go/ast"
+	"go/token"
+	"sort"
+	"strconv"
+
+	"golang.org/x/tools/go/exact"
+)
+
+// ident type-checks identifier e and initializes x with the value or type of e.
+// If an error occurred, x.mode is set to invalid.
+// For the meaning of def and path, see check.typ, below.
+//
+func (check *Checker) ident(x *operand, e *ast.Ident, def *Named, path []*TypeName) {
+	x.mode = invalid
+	x.expr = e
+
+	scope, obj := check.scope.LookupParent(e.Name, check.pos)
+	if obj == nil {
+		if e.Name == "_" {
+			check.errorf(e.Pos(), "cannot use _ as value or type")
+		} else {
+			check.errorf(e.Pos(), "undeclared name: %s", e.Name)
+		}
+		return
+	}
+	check.recordUse(e, obj)
+
+	check.objDecl(obj, def, path)
+	typ := obj.Type()
+	assert(typ != nil)
+
+	// The object may be dot-imported: If so, remove its package from
+	// the map of unused dot imports for the respective file scope.
+	// (This code is only needed for dot-imports. Without them,
+	// we only have to mark variables, see *Var case below).
+	if pkg := obj.Pkg(); pkg != check.pkg && pkg != nil {
+		delete(check.unusedDotImports[scope], pkg)
+	}
+
+	switch obj := obj.(type) {
+	case *PkgName:
+		check.errorf(e.Pos(), "use of package %s not in selector", obj.name)
+		return
+
+	case *Const:
+		check.addDeclDep(obj)
+		if typ == Typ[Invalid] {
+			return
+		}
+		if obj == universeIota {
+			if check.iota == nil {
+				check.errorf(e.Pos(), "cannot use iota outside constant declaration")
+				return
+			}
+			x.val = check.iota
+		} else {
+			x.val = obj.val
+		}
+		assert(x.val != nil)
+		x.mode = constant
+
+	case *TypeName:
+		x.mode = typexpr
+		// check for cycle
+		// (it's ok to iterate forward because each named type appears at most once in path)
+		for i, prev := range path {
+			if prev == obj {
+				check.errorf(obj.pos, "illegal cycle in declaration of %s", obj.name)
+				// print cycle
+				for _, obj := range path[i:] {
+					check.errorf(obj.Pos(), "\t%s refers to", obj.Name()) // secondary error, \t indented
+				}
+				check.errorf(obj.Pos(), "\t%s", obj.Name())
+				// maintain x.mode == typexpr despite error
+				typ = Typ[Invalid]
+				break
+			}
+		}
+
+	case *Var:
+		if obj.pkg == check.pkg {
+			obj.used = true
+		}
+		check.addDeclDep(obj)
+		if typ == Typ[Invalid] {
+			return
+		}
+		x.mode = variable
+
+	case *Func:
+		check.addDeclDep(obj)
+		x.mode = value
+
+	case *Builtin:
+		x.id = obj.id
+		x.mode = builtin
+
+	case *Nil:
+		x.mode = value
+
+	default:
+		unreachable()
+	}
+
+	x.typ = typ
+}
+
+// typExpr type-checks the type expression e and returns its type, or Typ[Invalid].
+// If def != nil, e is the type specification for the named type def, declared
+// in a type declaration, and def.underlying will be set to the type of e before
+// any components of e are type-checked. Path contains the path of named types
+// referring to this type.
+//
+func (check *Checker) typExpr(e ast.Expr, def *Named, path []*TypeName) (T Type) {
+	if trace {
+		check.trace(e.Pos(), "%s", e)
+		check.indent++
+		defer func() {
+			check.indent--
+			check.trace(e.Pos(), "=> %s", T)
+		}()
+	}
+
+	T = check.typExprInternal(e, def, path)
+	assert(isTyped(T))
+	check.recordTypeAndValue(e, typexpr, T, nil)
+
+	return
+}
+
+func (check *Checker) typ(e ast.Expr) Type {
+	return check.typExpr(e, nil, nil)
+}
+
+// funcType type-checks a function or method type.
+func (check *Checker) funcType(sig *Signature, recvPar *ast.FieldList, ftyp *ast.FuncType) {
+	scope := NewScope(check.scope, token.NoPos, token.NoPos, "function")
+	check.recordScope(ftyp, scope)
+
+	recvList, _ := check.collectParams(scope, recvPar, false)
+	params, variadic := check.collectParams(scope, ftyp.Params, true)
+	results, _ := check.collectParams(scope, ftyp.Results, false)
+
+	if recvPar != nil {
+		// recv parameter list present (may be empty)
+		// spec: "The receiver is specified via an extra parameter section preceeding the
+		// method name. That parameter section must declare a single parameter, the receiver."
+		var recv *Var
+		switch len(recvList) {
+		case 0:
+			check.error(recvPar.Pos(), "method is missing receiver")
+			recv = NewParam(0, nil, "", Typ[Invalid]) // ignore recv below
+		default:
+			// more than one receiver
+			check.error(recvList[len(recvList)-1].Pos(), "method must have exactly one receiver")
+			fallthrough // continue with first receiver
+		case 1:
+			recv = recvList[0]
+		}
+		// spec: "The receiver type must be of the form T or *T where T is a type name."
+		// (ignore invalid types - error was reported before)
+		if t, _ := deref(recv.typ); t != Typ[Invalid] {
+			var err string
+			if T, _ := t.(*Named); T != nil {
+				// spec: "The type denoted by T is called the receiver base type; it must not
+				// be a pointer or interface type and it must be declared in the same package
+				// as the method."
+				if T.obj.pkg != check.pkg {
+					err = "type not defined in this package"
+				} else {
+					// TODO(gri) This is not correct if the underlying type is unknown yet.
+					switch u := T.underlying.(type) {
+					case *Basic:
+						// unsafe.Pointer is treated like a regular pointer
+						if u.kind == UnsafePointer {
+							err = "unsafe.Pointer"
+						}
+					case *Pointer, *Interface:
+						err = "pointer or interface type"
+					}
+				}
+			} else {
+				err = "basic or unnamed type"
+			}
+			if err != "" {
+				check.errorf(recv.pos, "invalid receiver %s (%s)", recv.typ, err)
+				// ok to continue
+			}
+		}
+		sig.recv = recv
+	}
+
+	sig.scope = scope
+	sig.params = NewTuple(params...)
+	sig.results = NewTuple(results...)
+	sig.variadic = variadic
+}
+
+// typExprInternal drives type checking of types.
+// Must only be called by typExpr.
+//
+func (check *Checker) typExprInternal(e ast.Expr, def *Named, path []*TypeName) Type {
+	switch e := e.(type) {
+	case *ast.BadExpr:
+		// ignore - error reported before
+
+	case *ast.Ident:
+		var x operand
+		check.ident(&x, e, def, path)
+
+		switch x.mode {
+		case typexpr:
+			typ := x.typ
+			def.setUnderlying(typ)
+			return typ
+		case invalid:
+			// ignore - error reported before
+		case novalue:
+			check.errorf(x.pos(), "%s used as type", &x)
+		default:
+			check.errorf(x.pos(), "%s is not a type", &x)
+		}
+
+	case *ast.SelectorExpr:
+		var x operand
+		check.selector(&x, e)
+
+		switch x.mode {
+		case typexpr:
+			typ := x.typ
+			def.setUnderlying(typ)
+			return typ
+		case invalid:
+			// ignore - error reported before
+		case novalue:
+			check.errorf(x.pos(), "%s used as type", &x)
+		default:
+			check.errorf(x.pos(), "%s is not a type", &x)
+		}
+
+	case *ast.ParenExpr:
+		return check.typExpr(e.X, def, path)
+
+	case *ast.ArrayType:
+		if e.Len != nil {
+			typ := new(Array)
+			def.setUnderlying(typ)
+			typ.len = check.arrayLength(e.Len)
+			typ.elem = check.typExpr(e.Elt, nil, path)
+			return typ
+
+		} else {
+			typ := new(Slice)
+			def.setUnderlying(typ)
+			typ.elem = check.typ(e.Elt)
+			return typ
+		}
+
+	case *ast.StructType:
+		typ := new(Struct)
+		def.setUnderlying(typ)
+		check.structType(typ, e, path)
+		return typ
+
+	case *ast.StarExpr:
+		typ := new(Pointer)
+		def.setUnderlying(typ)
+		typ.base = check.typ(e.X)
+		return typ
+
+	case *ast.FuncType:
+		typ := new(Signature)
+		def.setUnderlying(typ)
+		check.funcType(typ, nil, e)
+		return typ
+
+	case *ast.InterfaceType:
+		typ := new(Interface)
+		def.setUnderlying(typ)
+		check.interfaceType(typ, e, def, path)
+		return typ
+
+	case *ast.MapType:
+		typ := new(Map)
+		def.setUnderlying(typ)
+
+		typ.key = check.typ(e.Key)
+		typ.elem = check.typ(e.Value)
+
+		// spec: "The comparison operators == and != must be fully defined
+		// for operands of the key type; thus the key type must not be a
+		// function, map, or slice."
+		//
+		// Delay this check because it requires fully setup types;
+		// it is safe to continue in any case (was issue 6667).
+		check.delay(func() {
+			if !Comparable(typ.key) {
+				check.errorf(e.Key.Pos(), "invalid map key type %s", typ.key)
+			}
+		})
+
+		return typ
+
+	case *ast.ChanType:
+		typ := new(Chan)
+		def.setUnderlying(typ)
+
+		dir := SendRecv
+		switch e.Dir {
+		case ast.SEND | ast.RECV:
+			// nothing to do
+		case ast.SEND:
+			dir = SendOnly
+		case ast.RECV:
+			dir = RecvOnly
+		default:
+			check.invalidAST(e.Pos(), "unknown channel direction %d", e.Dir)
+			// ok to continue
+		}
+
+		typ.dir = dir
+		typ.elem = check.typ(e.Value)
+		return typ
+
+	default:
+		check.errorf(e.Pos(), "%s is not a type", e)
+	}
+
+	typ := Typ[Invalid]
+	def.setUnderlying(typ)
+	return typ
+}
+
+// typeOrNil type-checks the type expression (or nil value) e
+// and returns the typ of e, or nil.
+// If e is neither a type nor nil, typOrNil returns Typ[Invalid].
+//
+func (check *Checker) typOrNil(e ast.Expr) Type {
+	var x operand
+	check.rawExpr(&x, e, nil)
+	switch x.mode {
+	case invalid:
+		// ignore - error reported before
+	case novalue:
+		check.errorf(x.pos(), "%s used as type", &x)
+	case typexpr:
+		return x.typ
+	case value:
+		if x.isNil() {
+			return nil
+		}
+		fallthrough
+	default:
+		check.errorf(x.pos(), "%s is not a type", &x)
+	}
+	return Typ[Invalid]
+}
+
+func (check *Checker) arrayLength(e ast.Expr) int64 {
+	var x operand
+	check.expr(&x, e)
+	if x.mode != constant {
+		if x.mode != invalid {
+			check.errorf(x.pos(), "array length %s must be constant", &x)
+		}
+		return 0
+	}
+	if !x.isInteger() {
+		check.errorf(x.pos(), "array length %s must be integer", &x)
+		return 0
+	}
+	n, ok := exact.Int64Val(x.val)
+	if !ok || n < 0 {
+		check.errorf(x.pos(), "invalid array length %s", &x)
+		return 0
+	}
+	return n
+}
+
+func (check *Checker) collectParams(scope *Scope, list *ast.FieldList, variadicOk bool) (params []*Var, variadic bool) {
+	if list == nil {
+		return
+	}
+
+	var named, anonymous bool
+	for i, field := range list.List {
+		ftype := field.Type
+		if t, _ := ftype.(*ast.Ellipsis); t != nil {
+			ftype = t.Elt
+			if variadicOk && i == len(list.List)-1 {
+				variadic = true
+			} else {
+				check.invalidAST(field.Pos(), "... not permitted")
+				// ignore ... and continue
+			}
+		}
+		typ := check.typ(ftype)
+		// The parser ensures that f.Tag is nil and we don't
+		// care if a constructed AST contains a non-nil tag.
+		if len(field.Names) > 0 {
+			// named parameter
+			for _, name := range field.Names {
+				if name.Name == "" {
+					check.invalidAST(name.Pos(), "anonymous parameter")
+					// ok to continue
+				}
+				par := NewParam(name.Pos(), check.pkg, name.Name, typ)
+				check.declare(scope, name, par, scope.pos)
+				params = append(params, par)
+			}
+			named = true
+		} else {
+			// anonymous parameter
+			par := NewParam(ftype.Pos(), check.pkg, "", typ)
+			check.recordImplicit(field, par)
+			params = append(params, par)
+			anonymous = true
+		}
+	}
+
+	if named && anonymous {
+		check.invalidAST(list.Pos(), "list contains both named and anonymous parameters")
+		// ok to continue
+	}
+
+	// For a variadic function, change the last parameter's type from T to []T.
+	if variadic && len(params) > 0 {
+		last := params[len(params)-1]
+		last.typ = &Slice{elem: last.typ}
+	}
+
+	return
+}
+
+func (check *Checker) declareInSet(oset *objset, pos token.Pos, obj Object) bool {
+	if alt := oset.insert(obj); alt != nil {
+		check.errorf(pos, "%s redeclared", obj.Name())
+		check.reportAltDecl(alt)
+		return false
+	}
+	return true
+}
+
+func (check *Checker) interfaceType(iface *Interface, ityp *ast.InterfaceType, def *Named, path []*TypeName) {
+	// empty interface: common case
+	if ityp.Methods == nil {
+		return
+	}
+
+	// The parser ensures that field tags are nil and we don't
+	// care if a constructed AST contains non-nil tags.
+
+	// use named receiver type if available (for better error messages)
+	var recvTyp Type = iface
+	if def != nil {
+		recvTyp = def
+	}
+
+	// Phase 1: Collect explicitly declared methods, the corresponding
+	//          signature (AST) expressions, and the list of embedded
+	//          type (AST) expressions. Do not resolve signatures or
+	//          embedded types yet to avoid cycles referring to this
+	//          interface.
+
+	var (
+		mset       objset
+		signatures []ast.Expr // list of corresponding method signatures
+		embedded   []ast.Expr // list of embedded types
+	)
+	for _, f := range ityp.Methods.List {
+		if len(f.Names) > 0 {
+			// The parser ensures that there's only one method
+			// and we don't care if a constructed AST has more.
+			name := f.Names[0]
+			pos := name.Pos()
+			// spec: "As with all method sets, in an interface type,
+			// each method must have a unique non-blank name."
+			if name.Name == "_" {
+				check.errorf(pos, "invalid method name _")
+				continue
+			}
+			// Don't type-check signature yet - use an
+			// empty signature now and update it later.
+			// Since we know the receiver, set it up now
+			// (required to avoid crash in ptrRecv; see
+			// e.g. test case for issue 6638).
+			// TODO(gri) Consider marking methods signatures
+			// as incomplete, for better error messages. See
+			// also the T4 and T5 tests in testdata/cycles2.src.
+			sig := new(Signature)
+			sig.recv = NewVar(pos, check.pkg, "", recvTyp)
+			m := NewFunc(pos, check.pkg, name.Name, sig)
+			if check.declareInSet(&mset, pos, m) {
+				iface.methods = append(iface.methods, m)
+				iface.allMethods = append(iface.allMethods, m)
+				signatures = append(signatures, f.Type)
+				check.recordDef(name, m)
+			}
+		} else {
+			// embedded type
+			embedded = append(embedded, f.Type)
+		}
+	}
+
+	// Phase 2: Resolve embedded interfaces. Because an interface must not
+	//          embed itself (directly or indirectly), each embedded interface
+	//          can be fully resolved without depending on any method of this
+	//          interface (if there is a cycle or another error, the embedded
+	//          type resolves to an invalid type and is ignored).
+	//          In particular, the list of methods for each embedded interface
+	//          must be complete (it cannot depend on this interface), and so
+	//          those methods can be added to the list of all methods of this
+	//          interface.
+
+	for _, e := range embedded {
+		pos := e.Pos()
+		typ := check.typExpr(e, nil, path)
+		// Determine underlying embedded (possibly incomplete) type
+		// by following its forward chain.
+		named, _ := typ.(*Named)
+		under := underlying(named)
+		embed, _ := under.(*Interface)
+		if embed == nil {
+			if typ != Typ[Invalid] {
+				check.errorf(pos, "%s is not an interface", typ)
+			}
+			continue
+		}
+		iface.embeddeds = append(iface.embeddeds, named)
+		// collect embedded methods
+		for _, m := range embed.allMethods {
+			if check.declareInSet(&mset, pos, m) {
+				iface.allMethods = append(iface.allMethods, m)
+			}
+		}
+	}
+
+	// Phase 3: At this point all methods have been collected for this interface.
+	//          It is now safe to type-check the signatures of all explicitly
+	//          declared methods, even if they refer to this interface via a cycle
+	//          and embed the methods of this interface in a parameter of interface
+	//          type.
+
+	for i, m := range iface.methods {
+		expr := signatures[i]
+		typ := check.typ(expr)
+		sig, _ := typ.(*Signature)
+		if sig == nil {
+			if typ != Typ[Invalid] {
+				check.invalidAST(expr.Pos(), "%s is not a method signature", typ)
+			}
+			continue // keep method with empty method signature
+		}
+		// update signature, but keep recv that was set up before
+		old := m.typ.(*Signature)
+		sig.recv = old.recv
+		*old = *sig // update signature (don't replace it!)
+	}
+
+	// TODO(gri) The list of explicit methods is only sorted for now to
+	// produce the same Interface as NewInterface. We may be able to
+	// claim source order in the future. Revisit.
+	sort.Sort(byUniqueMethodName(iface.methods))
+
+	// TODO(gri) The list of embedded types is only sorted for now to
+	// produce the same Interface as NewInterface. We may be able to
+	// claim source order in the future. Revisit.
+	sort.Sort(byUniqueTypeName(iface.embeddeds))
+
+	sort.Sort(byUniqueMethodName(iface.allMethods))
+}
+
+// byUniqueTypeName named type lists can be sorted by their unique type names.
+type byUniqueTypeName []*Named
+
+func (a byUniqueTypeName) Len() int           { return len(a) }
+func (a byUniqueTypeName) Less(i, j int) bool { return a[i].obj.Id() < a[j].obj.Id() }
+func (a byUniqueTypeName) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+
+// byUniqueMethodName method lists can be sorted by their unique method names.
+type byUniqueMethodName []*Func
+
+func (a byUniqueMethodName) Len() int           { return len(a) }
+func (a byUniqueMethodName) Less(i, j int) bool { return a[i].Id() < a[j].Id() }
+func (a byUniqueMethodName) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+
+func (check *Checker) tag(t *ast.BasicLit) string {
+	if t != nil {
+		if t.Kind == token.STRING {
+			if val, err := strconv.Unquote(t.Value); err == nil {
+				return val
+			}
+		}
+		check.invalidAST(t.Pos(), "incorrect tag syntax: %q", t.Value)
+	}
+	return ""
+}
+
+func (check *Checker) structType(styp *Struct, e *ast.StructType, path []*TypeName) {
+	list := e.Fields
+	if list == nil {
+		return
+	}
+
+	// struct fields and tags
+	var fields []*Var
+	var tags []string
+
+	// for double-declaration checks
+	var fset objset
+
+	// current field typ and tag
+	var typ Type
+	var tag string
+	// anonymous != nil indicates an anonymous field.
+	add := func(field *ast.Field, ident *ast.Ident, anonymous *TypeName, pos token.Pos) {
+		if tag != "" && tags == nil {
+			tags = make([]string, len(fields))
+		}
+		if tags != nil {
+			tags = append(tags, tag)
+		}
+
+		name := ident.Name
+		fld := NewField(pos, check.pkg, name, typ, anonymous != nil)
+		// spec: "Within a struct, non-blank field names must be unique."
+		if name == "_" || check.declareInSet(&fset, pos, fld) {
+			fields = append(fields, fld)
+			check.recordDef(ident, fld)
+		}
+		if anonymous != nil {
+			check.recordUse(ident, anonymous)
+		}
+	}
+
+	for _, f := range list.List {
+		typ = check.typExpr(f.Type, nil, path)
+		tag = check.tag(f.Tag)
+		if len(f.Names) > 0 {
+			// named fields
+			for _, name := range f.Names {
+				add(f, name, nil, name.Pos())
+			}
+		} else {
+			// anonymous field
+			name := anonymousFieldIdent(f.Type)
+			pos := f.Type.Pos()
+			t, isPtr := deref(typ)
+			switch t := t.(type) {
+			case *Basic:
+				if t == Typ[Invalid] {
+					// error was reported before
+					continue
+				}
+				// unsafe.Pointer is treated like a regular pointer
+				if t.kind == UnsafePointer {
+					check.errorf(pos, "anonymous field type cannot be unsafe.Pointer")
+					continue
+				}
+				add(f, name, Universe.Lookup(t.name).(*TypeName), pos)
+
+			case *Named:
+				// spec: "An embedded type must be specified as a type name
+				// T or as a pointer to a non-interface type name *T, and T
+				// itself may not be a pointer type."
+				switch u := t.underlying.(type) {
+				case *Basic:
+					// unsafe.Pointer is treated like a regular pointer
+					if u.kind == UnsafePointer {
+						check.errorf(pos, "anonymous field type cannot be unsafe.Pointer")
+						continue
+					}
+				case *Pointer:
+					check.errorf(pos, "anonymous field type cannot be a pointer")
+					continue
+				case *Interface:
+					if isPtr {
+						check.errorf(pos, "anonymous field type cannot be a pointer to an interface")
+						continue
+					}
+				}
+				add(f, name, t.obj, pos)
+
+			default:
+				check.invalidAST(pos, "anonymous field type %s must be named", typ)
+			}
+		}
+	}
+
+	styp.fields = fields
+	styp.tags = tags
+}
+
+func anonymousFieldIdent(e ast.Expr) *ast.Ident {
+	switch e := e.(type) {
+	case *ast.Ident:
+		return e
+	case *ast.StarExpr:
+		return anonymousFieldIdent(e.X)
+	case *ast.SelectorExpr:
+		return e.Sel
+	}
+	return nil // invalid anonymous field
+}

Godeps/_workspace/src/golang.org/x/tools/go/types/universe.go

@@ -0,0 +1,224 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file sets up the universe scope and the unsafe package.
+
+package types
+
+import (
+	"go/token"
+	"strings"
+
+	"golang.org/x/tools/go/exact"
+)
+
+var (
+	Universe     *Scope
+	Unsafe       *Package
+	universeIota *Const
+	universeByte *Basic // uint8 alias, but has name "byte"
+	universeRune *Basic // int32 alias, but has name "rune"
+)
+
+var Typ = []*Basic{
+	Invalid: {Invalid, 0, "invalid type"},
+
+	Bool:          {Bool, IsBoolean, "bool"},
+	Int:           {Int, IsInteger, "int"},
+	Int8:          {Int8, IsInteger, "int8"},
+	Int16:         {Int16, IsInteger, "int16"},
+	Int32:         {Int32, IsInteger, "int32"},
+	Int64:         {Int64, IsInteger, "int64"},
+	Uint:          {Uint, IsInteger | IsUnsigned, "uint"},
+	Uint8:         {Uint8, IsInteger | IsUnsigned, "uint8"},
+	Uint16:        {Uint16, IsInteger | IsUnsigned, "uint16"},
+	Uint32:        {Uint32, IsInteger | IsUnsigned, "uint32"},
+	Uint64:        {Uint64, IsInteger | IsUnsigned, "uint64"},
+	Uintptr:       {Uintptr, IsInteger | IsUnsigned, "uintptr"},
+	Float32:       {Float32, IsFloat, "float32"},
+	Float64:       {Float64, IsFloat, "float64"},
+	Complex64:     {Complex64, IsComplex, "complex64"},
+	Complex128:    {Complex128, IsComplex, "complex128"},
+	String:        {String, IsString, "string"},
+	UnsafePointer: {UnsafePointer, 0, "Pointer"},
+
+	UntypedBool:    {UntypedBool, IsBoolean | IsUntyped, "untyped bool"},
+	UntypedInt:     {UntypedInt, IsInteger | IsUntyped, "untyped int"},
+	UntypedRune:    {UntypedRune, IsInteger | IsUntyped, "untyped rune"},
+	UntypedFloat:   {UntypedFloat, IsFloat | IsUntyped, "untyped float"},
+	UntypedComplex: {UntypedComplex, IsComplex | IsUntyped, "untyped complex"},
+	UntypedString:  {UntypedString, IsString | IsUntyped, "untyped string"},
+	UntypedNil:     {UntypedNil, IsUntyped, "untyped nil"},
+}
+
+var aliases = [...]*Basic{
+	{Byte, IsInteger | IsUnsigned, "byte"},
+	{Rune, IsInteger, "rune"},
+}
+
+func defPredeclaredTypes() {
+	for _, t := range Typ {
+		def(NewTypeName(token.NoPos, nil, t.name, t))
+	}
+	for _, t := range aliases {
+		def(NewTypeName(token.NoPos, nil, t.name, t))
+	}
+
+	// Error has a nil package in its qualified name since it is in no package
+	res := NewVar(token.NoPos, nil, "", Typ[String])
+	sig := &Signature{results: NewTuple(res)}
+	err := NewFunc(token.NoPos, nil, "Error", sig)
+	typ := &Named{underlying: NewInterface([]*Func{err}, nil).Complete()}
+	sig.recv = NewVar(token.NoPos, nil, "", typ)
+	def(NewTypeName(token.NoPos, nil, "error", typ))
+}
+
+var predeclaredConsts = [...]struct {
+	name string
+	kind BasicKind
+	val  exact.Value
+}{
+	{"true", UntypedBool, exact.MakeBool(true)},
+	{"false", UntypedBool, exact.MakeBool(false)},
+	{"iota", UntypedInt, exact.MakeInt64(0)},
+}
+
+func defPredeclaredConsts() {
+	for _, c := range predeclaredConsts {
+		def(NewConst(token.NoPos, nil, c.name, Typ[c.kind], c.val))
+	}
+}
+
+func defPredeclaredNil() {
+	def(&Nil{object{name: "nil", typ: Typ[UntypedNil]}})
+}
+
+// A builtinId is the id of a builtin function.
+type builtinId int
+
+const (
+	// universe scope
+	_Append builtinId = iota
+	_Cap
+	_Close
+	_Complex
+	_Copy
+	_Delete
+	_Imag
+	_Len
+	_Make
+	_New
+	_Panic
+	_Print
+	_Println
+	_Real
+	_Recover
+
+	// package unsafe
+	_Alignof
+	_Offsetof
+	_Sizeof
+
+	// testing support
+	_Assert
+	_Trace
+)
+
+var predeclaredFuncs = [...]struct {
+	name     string
+	nargs    int
+	variadic bool
+	kind     exprKind
+}{
+	_Append:  {"append", 1, true, expression},
+	_Cap:     {"cap", 1, false, expression},
+	_Close:   {"close", 1, false, statement},
+	_Complex: {"complex", 2, false, expression},
+	_Copy:    {"copy", 2, false, statement},
+	_Delete:  {"delete", 2, false, statement},
+	_Imag:    {"imag", 1, false, expression},
+	_Len:     {"len", 1, false, expression},
+	_Make:    {"make", 1, true, expression},
+	_New:     {"new", 1, false, expression},
+	_Panic:   {"panic", 1, false, statement},
+	_Print:   {"print", 0, true, statement},
+	_Println: {"println", 0, true, statement},
+	_Real:    {"real", 1, false, expression},
+	_Recover: {"recover", 0, false, statement},
+
+	_Alignof:  {"Alignof", 1, false, expression},
+	_Offsetof: {"Offsetof", 1, false, expression},
+	_Sizeof:   {"Sizeof", 1, false, expression},
+
+	_Assert: {"assert", 1, false, statement},
+	_Trace:  {"trace", 0, true, statement},
+}
+
+func defPredeclaredFuncs() {
+	for i := range predeclaredFuncs {
+		id := builtinId(i)
+		if id == _Assert || id == _Trace {
+			continue // only define these in testing environment
+		}
+		def(newBuiltin(id))
+	}
+}
+
+// DefPredeclaredTestFuncs defines the assert and trace built-ins.
+// These built-ins are intended for debugging and testing of this
+// package only.
+func DefPredeclaredTestFuncs() {
+	if Universe.Lookup("assert") != nil {
+		return // already defined
+	}
+	def(newBuiltin(_Assert))
+	def(newBuiltin(_Trace))
+}
+
+func init() {
+	Universe = NewScope(nil, token.NoPos, token.NoPos, "universe")
+	Unsafe = NewPackage("unsafe", "unsafe")
+	Unsafe.complete = true
+
+	defPredeclaredTypes()
+	defPredeclaredConsts()
+	defPredeclaredNil()
+	defPredeclaredFuncs()
+
+	universeIota = Universe.Lookup("iota").(*Const)
+	universeByte = Universe.Lookup("byte").(*TypeName).typ.(*Basic)
+	universeRune = Universe.Lookup("rune").(*TypeName).typ.(*Basic)
+}
+
+// Objects with names containing blanks are internal and not entered into
+// a scope. Objects with exported names are inserted in the unsafe package
+// scope; other objects are inserted in the universe scope.
+//
+func def(obj Object) {
+	name := obj.Name()
+	if strings.Index(name, " ") >= 0 {
+		return // nothing to do
+	}
+	// fix Obj link for named types
+	if typ, ok := obj.Type().(*Named); ok {
+		typ.obj = obj.(*TypeName)
+	}
+	// exported identifiers go into package unsafe
+	scope := Universe
+	if obj.Exported() {
+		scope = Unsafe.scope
+		// set Pkg field
+		switch obj := obj.(type) {
+		case *TypeName:
+			obj.pkg = Unsafe
+		case *Builtin:
+			obj.pkg = Unsafe
+		default:
+			unreachable()
+		}
+	}
+	if scope.Insert(obj) != nil {
+		panic("internal error: double declaration")
+	}
+}

rpc/genapi.go

@@ -5,7 +5,11 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/compiler"
+	"github.com/ethereum/go-ethereum/core/state"
+	"github.com/ethereum/go-ethereum/eth"
+	"github.com/ethereum/go-ethereum/rpc/api"
 	"github.com/ethereum/go-ethereum/rpc/comms"
+	"github.com/ethereum/go-ethereum/xeth"
 )
 
 type GenApi struct {
@@ -91,11 +95,24 @@ func (self *Admin) ImportChain() (result bool, failure error) {
 	}
 	return res.(bool), nil
 }
-func (self *Admin) NodeInfo() (interface{}, error) {
+func (self *Admin) NodeInfo() (result *eth.NodeInfo, failure error) {
-	return self.xeth.Call("admin_nodeInfo", nil)
+	res, err := self.xeth.Call("admin_nodeInfo", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(*eth.NodeInfo), nil
 }
-func (self *Admin) Peers() (interface{}, error) {
+func (self *Admin) Peers() (result []*eth.PeerInfo, failure error) {
-	return self.xeth.Call("admin_peers", nil)
+	res, err := self.xeth.Call("admin_peers", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	for _, item := range res.([]interface{}) {
+		result = append(result, item.(*eth.PeerInfo))
+	}
+	return
 }
 func (self *Admin) Register(sender string, address string, contentHashHex string) (result bool, failure error) {
 	res, err := self.xeth.Call("admin_register", []interface{}{sender, address, contentHashHex})
@@ -113,8 +130,13 @@ func (self *Admin) RegisterUrl(sender string, contentHash string, url string) (r
 	}
 	return res.(bool), nil
 }
-func (self *Admin) SaveInfo(contractInfo compiler.ContractInfo, filename string) (interface{}, error) {
+func (self *Admin) SaveInfo(contractInfo compiler.ContractInfo, filename string) (result string, failure error) {
-	return self.xeth.Call("admin_saveInfo", []interface{}{contractInfo, filename})
+	res, err := self.xeth.Call("admin_saveInfo", []interface{}{contractInfo, filename})
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(string), nil
 }
 func (self *Admin) SetGlobalRegistrar(nameReg string, contractAddress string) (interface{}, error) {
 	return self.xeth.Call("admin_setGlobalRegistrar", []interface{}{nameReg, contractAddress})
@@ -122,8 +144,13 @@ func (self *Admin) SetGlobalRegistrar(nameReg string, contractAddress string) (i
 func (self *Admin) SetHashReg(hashReg string, sender string) (interface{}, error) {
 	return self.xeth.Call("admin_setHashReg", []interface{}{hashReg, sender})
 }
-func (self *Admin) SetSolc(path string) (interface{}, error) {
+func (self *Admin) SetSolc(path string) (result string, failure error) {
-	return self.xeth.Call("admin_setSolc", []interface{}{path})
+	res, err := self.xeth.Call("admin_setSolc", []interface{}{path})
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(string), nil
 }
 func (self *Admin) SetUrlHint(urlHint string, sender string) (interface{}, error) {
 	return self.xeth.Call("admin_setUrlHint", []interface{}{urlHint, sender})
@@ -131,8 +158,13 @@ func (self *Admin) SetUrlHint(urlHint string, sender string) (interface{}, error
 func (self *Admin) Sleep(s int) (interface{}, error) {
 	return self.xeth.Call("admin_sleep", []interface{}{s})
 }
-func (self *Admin) SleepBlocks(n int64, timeout int64) (interface{}, error) {
+func (self *Admin) SleepBlocks(n int64, timeout int64) (result uint64, failure error) {
-	return self.xeth.Call("admin_sleepBlocks", []interface{}{n, timeout})
+	res, err := self.xeth.Call("admin_sleepBlocks", []interface{}{n, timeout})
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(uint64), nil
 }
 func (self *Admin) StartNatSpec() (result bool, failure error) {
 	res, err := self.xeth.Call("admin_startNatSpec", nil)
@@ -179,8 +211,13 @@ type Db struct {
 	xeth *Xeth
 }
 
-func (self *Db) GetHex() (interface{}, error) {
+func (self *Db) GetHex() (result []byte, failure error) {
-	return self.xeth.Call("db_getHex", nil)
+	res, err := self.xeth.Call("db_getHex", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.([]byte), nil
 }
 func (self *Db) GetString() (result string, failure error) {
 	res, err := self.xeth.Call("db_getString", nil)
@@ -190,19 +227,34 @@ func (self *Db) GetString() (result string, failure error) {
 	}
 	return res.(string), nil
 }
-func (self *Db) PutHex() (interface{}, error) {
+func (self *Db) PutHex() (result bool, failure error) {
-	return self.xeth.Call("db_putHex", nil)
+	res, err := self.xeth.Call("db_putHex", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(bool), nil
 }
-func (self *Db) PutString() (interface{}, error) {
+func (self *Db) PutString() (result bool, failure error) {
-	return self.xeth.Call("db_putString", nil)
+	res, err := self.xeth.Call("db_putString", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(bool), nil
 }
 
 type Debug struct {
 	xeth *Xeth
 }
 
-func (self *Debug) DumpBlock() (interface{}, error) {
+func (self *Debug) DumpBlock() (result state.World, failure error) {
-	return self.xeth.Call("debug_dumpBlock", nil)
+	res, err := self.xeth.Call("debug_dumpBlock", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(state.World), nil
 }
 func (self *Debug) GetBlockRlp() (interface{}, error) {
 	return self.xeth.Call("debug_getBlockRlp", nil)
@@ -232,8 +284,16 @@ type Eth struct {
 	xeth *Xeth
 }
 
-func (self *Eth) Accounts() (interface{}, error) {
+func (self *Eth) Accounts() (result []string, failure error) {
-	return self.xeth.Call("eth_accounts", nil)
+	res, err := self.xeth.Call("eth_accounts", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	for _, item := range res.([]interface{}) {
+		result = append(result, item.(string))
+	}
+	return
 }
 func (self *Eth) BlockNumber() (result int64, failure error) {
 	res, err := self.xeth.Call("eth_blockNumber", nil)
@@ -243,11 +303,21 @@ func (self *Eth) BlockNumber() (result int64, failure error) {
 	}
 	return new(big.Int).SetBytes(common.FromHex(res.(string))).Int64(), nil
 }
-func (self *Eth) Call(from string, to string, value *big.Int, gas *big.Int, gasPrice *big.Int, data string, blockNumber int64) (interface{}, error) {
+func (self *Eth) Call(from string, to string, value *big.Int, gas *big.Int, gasPrice *big.Int, data string, blockNumber int64) (result []byte, failure error) {
-	return self.xeth.Call("eth_call", []interface{}{from, to, value, gas, gasPrice, data, blockNumber})
+	res, err := self.xeth.Call("eth_call", []interface{}{from, to, value, gas, gasPrice, data, blockNumber})
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.([]byte), nil
 }
-func (self *Eth) Coinbase() (interface{}, error) {
+func (self *Eth) Coinbase() (result []byte, failure error) {
-	return self.xeth.Call("eth_coinbase", nil)
+	res, err := self.xeth.Call("eth_coinbase", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.([]byte), nil
 }
 func (self *Eth) CompileSolidity() (interface{}, error) {
 	return self.xeth.Call("eth_compileSolidity", nil)
@@ -271,11 +341,21 @@ func (self *Eth) GasPrice(price string) (result int64, failure error) {
 	}
 	return new(big.Int).SetBytes(common.FromHex(res.(string))).Int64(), nil
 }
-func (self *Eth) GetBalance(address string, blockNumber int64) (interface{}, error) {
+func (self *Eth) GetBalance(address string, blockNumber int64) (result string, failure error) {
-	return self.xeth.Call("eth_getBalance", []interface{}{address, blockNumber})
+	res, err := self.xeth.Call("eth_getBalance", []interface{}{address, blockNumber})
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(string), nil
 }
-func (self *Eth) GetBlockByHash(blockHash string, includeTxs bool) (interface{}, error) {
+func (self *Eth) GetBlockByHash(blockHash string, includeTxs bool) (result *api.BlockRes, failure error) {
-	return self.xeth.Call("eth_getBlockByHash", []interface{}{blockHash, includeTxs})
+	res, err := self.xeth.Call("eth_getBlockByHash", []interface{}{blockHash, includeTxs})
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(*api.BlockRes), nil
 }
 func (self *Eth) GetBlockByNumber(blockNumber int64, includeTxs bool) (interface{}, error) {
 	return self.xeth.Call("eth_getBlockByNumber", []interface{}{blockNumber, includeTxs})
@@ -286,29 +366,65 @@ func (self *Eth) GetBlockTransactionCountByHash() (interface{}, error) {
 func (self *Eth) GetBlockTransactionCountByNumber() (interface{}, error) {
 	return self.xeth.Call("eth_getBlockTransactionCountByNumber", nil)
 }
-func (self *Eth) GetCode(address string, blockNumber int64) (interface{}, error) {
+func (self *Eth) GetCode(address string, blockNumber int64) (result []byte, failure error) {
-	return self.xeth.Call("eth_getCode", []interface{}{address, blockNumber})
+	res, err := self.xeth.Call("eth_getCode", []interface{}{address, blockNumber})
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.([]byte), nil
 }
 func (self *Eth) GetCompilers() (interface{}, error) {
 	return self.xeth.Call("eth_getCompilers", nil)
 }
-func (self *Eth) GetData(address string, blockNumber int64) (interface{}, error) {
+func (self *Eth) GetData(address string, blockNumber int64) (result []byte, failure error) {
-	return self.xeth.Call("eth_getData", []interface{}{address, blockNumber})
+	res, err := self.xeth.Call("eth_getData", []interface{}{address, blockNumber})
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.([]byte), nil
 }
 func (self *Eth) GetFilterChanges() (interface{}, error) {
 	return self.xeth.Call("eth_getFilterChanges", nil)
 }
-func (self *Eth) GetFilterLogs() (interface{}, error) {
+func (self *Eth) GetFilterLogs() (result []api.LogRes, failure error) {
-	return self.xeth.Call("eth_getFilterLogs", nil)
+	res, err := self.xeth.Call("eth_getFilterLogs", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	for _, item := range res.([]interface{}) {
+		result = append(result, item.(api.LogRes))
+	}
+	return
 }
-func (self *Eth) GetLogs() (interface{}, error) {
+func (self *Eth) GetLogs() (result []api.LogRes, failure error) {
-	return self.xeth.Call("eth_getLogs", nil)
+	res, err := self.xeth.Call("eth_getLogs", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	for _, item := range res.([]interface{}) {
+		result = append(result, item.(api.LogRes))
+	}
+	return
 }
-func (self *Eth) GetStorage(address string, blockNumber int64) (interface{}, error) {
+func (self *Eth) GetStorage(address string, blockNumber int64) (result map[string]string, failure error) {
-	return self.xeth.Call("eth_getStorage", []interface{}{address, blockNumber})
+	res, err := self.xeth.Call("eth_getStorage", []interface{}{address, blockNumber})
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(map[string]string), nil
 }
-func (self *Eth) GetStorageAt(address string, blockNumber int64, key string) (interface{}, error) {
+func (self *Eth) GetStorageAt(address string, blockNumber int64, key string) (result string, failure error) {
-	return self.xeth.Call("eth_getStorageAt", []interface{}{address, blockNumber, key})
+	res, err := self.xeth.Call("eth_getStorageAt", []interface{}{address, blockNumber, key})
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(string), nil
 }
 func (self *Eth) GetTransactionByBlockHashAndIndex() (interface{}, error) {
 	return self.xeth.Call("eth_getTransactionByBlockHashAndIndex", nil)
@@ -352,8 +468,13 @@ func (self *Eth) GetUncleCountByBlockNumber() (result int64, failure error) {
 	}
 	return new(big.Int).SetBytes(common.FromHex(res.(string))).Int64(), nil
 }
-func (self *Eth) GetWork() (interface{}, error) {
+func (self *Eth) GetWork() (result [3]string, failure error) {
-	return self.xeth.Call("eth_getWork", nil)
+	res, err := self.xeth.Call("eth_getWork", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.([3]string), nil
 }
 func (self *Eth) Hashrate() (result int64, failure error) {
 	res, err := self.xeth.Call("eth_hashrate", nil)
@@ -363,8 +484,13 @@ func (self *Eth) Hashrate() (result int64, failure error) {
 	}
 	return new(big.Int).SetBytes(common.FromHex(res.(string))).Int64(), nil
 }
-func (self *Eth) Mining() (interface{}, error) {
+func (self *Eth) Mining() (result bool, failure error) {
-	return self.xeth.Call("eth_mining", nil)
+	res, err := self.xeth.Call("eth_mining", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(bool), nil
 }
 func (self *Eth) NewBlockFilter() (result int64, failure error) {
 	res, err := self.xeth.Call("eth_newBlockFilter", nil)
@@ -393,8 +519,13 @@ func (self *Eth) NewPendingTransactionFilter() (result int64, failure error) {
 func (self *Eth) PendingTransactions() (interface{}, error) {
 	return self.xeth.Call("eth_pendingTransactions", nil)
 }
-func (self *Eth) ProtocolVersion() (interface{}, error) {
+func (self *Eth) ProtocolVersion() (result string, failure error) {
-	return self.xeth.Call("eth_protocolVersion", nil)
+	res, err := self.xeth.Call("eth_protocolVersion", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(string), nil
 }
 func (self *Eth) SendRawTransaction() (interface{}, error) {
 	return self.xeth.Call("eth_sendRawTransaction", nil)
@@ -405,8 +536,13 @@ func (self *Eth) SendTransaction() (interface{}, error) {
 func (self *Eth) Sign() (interface{}, error) {
 	return self.xeth.Call("eth_sign", nil)
 }
-func (self *Eth) StorageAt(address string, blockNumber int64) (interface{}, error) {
+func (self *Eth) StorageAt(address string, blockNumber int64) (result map[string]string, failure error) {
-	return self.xeth.Call("eth_storageAt", []interface{}{address, blockNumber})
+	res, err := self.xeth.Call("eth_storageAt", []interface{}{address, blockNumber})
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(map[string]string), nil
 }
 func (self *Eth) SubmitHashrate() (result bool, failure error) {
 	res, err := self.xeth.Call("eth_submitHashrate", nil)
@@ -416,22 +552,37 @@ func (self *Eth) SubmitHashrate() (result bool, failure error) {
 	}
 	return res.(bool), nil
 }
-func (self *Eth) SubmitWork(nonce uint64, header string, digest string) (interface{}, error) {
+func (self *Eth) SubmitWork(nonce uint64, header string, digest string) (result bool, failure error) {
-	return self.xeth.Call("eth_submitWork", []interface{}{nonce, header, digest})
+	res, err := self.xeth.Call("eth_submitWork", []interface{}{nonce, header, digest})
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(bool), nil
 }
 func (self *Eth) Transact() (interface{}, error) {
 	return self.xeth.Call("eth_transact", nil)
 }
-func (self *Eth) UninstallFilter() (interface{}, error) {
+func (self *Eth) UninstallFilter() (result bool, failure error) {
-	return self.xeth.Call("eth_uninstallFilter", nil)
+	res, err := self.xeth.Call("eth_uninstallFilter", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(bool), nil
 }
 
 type Miner struct {
 	xeth *Xeth
 }
 
-func (self *Miner) Hashrate() (interface{}, error) {
+func (self *Miner) Hashrate() (result int64, failure error) {
-	return self.xeth.Call("miner_hashrate", nil)
+	res, err := self.xeth.Call("miner_hashrate", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return new(big.Int).SetBytes(common.FromHex(res.(string))).Int64(), nil
 }
 func (self *Miner) MakeDAG(blockNumber int64) (result bool, failure error) {
 	res, err := self.xeth.Call("miner_makeDAG", []interface{}{blockNumber})
@@ -497,8 +648,13 @@ type Net struct {
 	xeth *Xeth
 }
 
-func (self *Net) Listening() (interface{}, error) {
+func (self *Net) Listening() (result bool, failure error) {
-	return self.xeth.Call("net_listening", nil)
+	res, err := self.xeth.Call("net_listening", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(bool), nil
 }
 func (self *Net) PeerCount() (result int64, failure error) {
 	res, err := self.xeth.Call("net_peerCount", nil)
@@ -508,36 +664,80 @@ func (self *Net) PeerCount() (result int64, failure error) {
 	}
 	return new(big.Int).SetBytes(common.FromHex(res.(string))).Int64(), nil
 }
-func (self *Net) Version() (interface{}, error) {
+func (self *Net) Version() (result string, failure error) {
-	return self.xeth.Call("net_version", nil)
+	res, err := self.xeth.Call("net_version", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(string), nil
 }
 
 type Personal struct {
 	xeth *Xeth
 }
 
-func (self *Personal) ListAccounts() (interface{}, error) {
+func (self *Personal) ListAccounts() (result []string, failure error) {
-	return self.xeth.Call("personal_listAccounts", nil)
+	res, err := self.xeth.Call("personal_listAccounts", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	for _, item := range res.([]interface{}) {
+		result = append(result, item.(string))
+	}
+	return
 }
-func (self *Personal) NewAccount(passphrase string) (interface{}, error) {
+func (self *Personal) NewAccount(passphrase string) (result string, failure error) {
-	return self.xeth.Call("personal_newAccount", []interface{}{passphrase})
+	res, err := self.xeth.Call("personal_newAccount", []interface{}{passphrase})
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(string), nil
 }
-func (self *Personal) UnlockAccount(address string, passphrase string, duration int) (interface{}, error) {
+func (self *Personal) UnlockAccount(address string, passphrase string, duration int) (result bool, failure error) {
-	return self.xeth.Call("personal_unlockAccount", []interface{}{address, passphrase, duration})
+	res, err := self.xeth.Call("personal_unlockAccount", []interface{}{address, passphrase, duration})
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(bool), nil
 }
 
 type Shh struct {
 	xeth *Xeth
 }
 
-func (self *Shh) GetFilterChanges() (interface{}, error) {
+func (self *Shh) GetFilterChanges() (result []xeth.WhisperMessage, failure error) {
-	return self.xeth.Call("shh_getFilterChanges", nil)
+	res, err := self.xeth.Call("shh_getFilterChanges", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	for _, item := range res.([]interface{}) {
+		result = append(result, item.(xeth.WhisperMessage))
+	}
+	return
 }
-func (self *Shh) GetMessages() (interface{}, error) {
+func (self *Shh) GetMessages() (result []xeth.WhisperMessage, failure error) {
-	return self.xeth.Call("shh_getMessages", nil)
+	res, err := self.xeth.Call("shh_getMessages", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	for _, item := range res.([]interface{}) {
+		result = append(result, item.(xeth.WhisperMessage))
+	}
+	return
 }
-func (self *Shh) HasIdentity() (interface{}, error) {
+func (self *Shh) HasIdentity() (result bool, failure error) {
-	return self.xeth.Call("shh_hasIdentity", nil)
+	res, err := self.xeth.Call("shh_hasIdentity", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(bool), nil
 }
 func (self *Shh) NewFilter() (result int64, failure error) {
 	res, err := self.xeth.Call("shh_newFilter", nil)
@@ -547,8 +747,13 @@ func (self *Shh) NewFilter() (result int64, failure error) {
 	}
 	return new(big.Int).SetBytes(common.FromHex(res.(string))).Int64(), nil
 }
-func (self *Shh) NewIdentity() (interface{}, error) {
+func (self *Shh) NewIdentity() (result string, failure error) {
-	return self.xeth.Call("shh_newIdentity", nil)
+	res, err := self.xeth.Call("shh_newIdentity", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(string), nil
 }
 func (self *Shh) Post() (result bool, failure error) {
 	res, err := self.xeth.Call("shh_post", nil)
@@ -558,11 +763,21 @@ func (self *Shh) Post() (result bool, failure error) {
 	}
 	return res.(bool), nil
 }
-func (self *Shh) UninstallFilter() (interface{}, error) {
+func (self *Shh) UninstallFilter() (result bool, failure error) {
-	return self.xeth.Call("shh_uninstallFilter", nil)
+	res, err := self.xeth.Call("shh_uninstallFilter", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(bool), nil
 }
-func (self *Shh) Version() (interface{}, error) {
+func (self *Shh) Version() (result uint, failure error) {
-	return self.xeth.Call("shh_version", nil)
+	res, err := self.xeth.Call("shh_version", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(uint), nil
 }
 
 type Txpool struct {
@@ -577,8 +792,13 @@ type Web3 struct {
 	xeth *Xeth
 }
 
-func (self *Web3) ClientVersion() (interface{}, error) {
+func (self *Web3) ClientVersion() (result string, failure error) {
-	return self.xeth.Call("web3_clientVersion", nil)
+	res, err := self.xeth.Call("web3_clientVersion", nil)
+	if err != nil {
+		failure = err
+		return
+	}
+	return res.(string), nil
 }
 func (self *Web3) Sha3(data string) (interface{}, error) {
 	return self.xeth.Call("web3_sha3", []interface{}{data})

rpc/generator/generator.go

@@ -31,10 +31,13 @@ import (
 	"os/exec"
 	"path/filepath"
 	"reflect"
+	"regexp"
 	"sort"
 	"strings"
 	"unicode"
 
+	"golang.org/x/tools/go/loader"
+	"golang.org/x/tools/go/types"
 	"golang.org/x/tools/imports"
 )
 
@@ -53,6 +56,16 @@ type Endpoint struct {
 }
 
 func main() {
+	// Load the entire package and dependencies for static analysis
+	conf := new(loader.Config)
+	conf.Import("github.com/ethereum/go-ethereum/rpc/api")
+
+	prog, err := conf.Load()
+	if err != nil {
+		log.Fatalf("Failed to load API package: %v", err)
+	}
+	info := prog.Imported["github.com/ethereum/go-ethereum/rpc/api"].Info
+
 	// Iterate over all the API files and collect the top level declarations
 	api, err := details("github.com/ethereum/go-ethereum/rpc/api")
 	if err != nil {
@@ -63,7 +76,7 @@ func main() {
 		log.Fatalf("Failed to collect API declarations: %v", err)
 	}
 	// Gather all the deteced API endpoints
-	methods, err := endpoints(funs, types, values)
+	methods, err := endpoints(info, funs, types, values)
 	if err != nil {
 		log.Fatalf("Failed to gather API endpoints: %v", err)
 	}
@@ -163,8 +176,23 @@ func returns(block *ast.BlockStmt) []*ast.ReturnStmt {
 	return results
 }
 
+// flatten converts a possibly multi selextor expression into a string identifier.
+func flatten(sel ast.Expr) string {
+	switch x := sel.(type) {
+	case *ast.Ident:
+		return x.String()
+	case *ast.SelectorExpr:
+		return flatten(x.X) + "." + x.Sel.String()
+	case *ast.CallExpr:
+		return flatten(x.Fun) + "()"
+	default:
+		//fmt.Println("unknown selector to flatten", reflect.TypeOf(sel.X))
+	}
+	return ""
+}
+
 // endpoints collects the detected RPC API method endpoints.
-func endpoints(funs map[string]*ast.BlockStmt, types map[string]*ast.TypeSpec, values map[string]ast.Expr) (map[string][]*Endpoint, error) {
+func endpoints(info types.Info, funs map[string]*ast.BlockStmt, typeDecls map[string]*ast.TypeSpec, values map[string]ast.Expr) (map[string][]*Endpoint, error) {
 	methods := make(map[string][]*Endpoint)
 
 	// Iterate over all the API mappings, and locate the RPC function associations
@@ -185,7 +213,7 @@ func endpoints(funs map[string]*ast.BlockStmt, types map[string]*ast.TypeSpec, v
 
 				// Generate the parameter list
 				params, paramList := []string{}, []string{}
-				if arg := types[args]; arg != nil {
+				if arg := typeDecls[args]; arg != nil {
 					for _, field := range arg.Type.(*ast.StructType).Fields.List {
 						variable := field.Names[0].String()
 						variable = string(unicode.ToLower(rune(variable[0]))) + variable[1:]
@@ -219,8 +247,7 @@ func endpoints(funs map[string]*ast.BlockStmt, types map[string]*ast.TypeSpec, v
 
 				result := "interface{}"
 				for _, ret := range rets {
-					res := ret.Results[0]
+					switch res := ret.Results[0].(type) {
-					switch res := res.(type) {
 					case *ast.Ident:
 						if res.String() == "nil" {
 							break
@@ -235,14 +262,37 @@ func endpoints(funs map[string]*ast.BlockStmt, types map[string]*ast.TypeSpec, v
 								result = "string"
 							} else if ident.String() == "newHexNum" {
 								result = "int64"
+							} else if ident.String() == "newHexData" {
+								result = "[]byte"
 							} else {
+								for match, def := range info.Defs {
+									if ident.String() == match.String() {
+										result = def.Type().(*types.Signature).Results().At(0).Type().String()
+										if strings.Contains(result, "/") {
+											result = regexp.MustCompile("[a-zA-Z0-9-\\.]+/").ReplaceAllString(result, "")
+										}
+									}
+								}
+								if result == "interface{}" {
 									fmt.Println(owner, method, res, "unknown ident funcion")
 								}
+							}
+						} else if sel, ok := res.Fun.(*ast.SelectorExpr); ok {
+							if selector := flatten(sel); selector != "" {
+								for match, selection := range info.Selections {
+									if flatten(match) == selector {
+										result = selection.Type().(*types.Signature).Results().At(0).Type().String()
+										if strings.Contains(result, "/") {
+											result = regexp.MustCompile("[a-zA-Z0-9-\\.]+/").ReplaceAllString(result, "")
+										}
+									}
+								}
+							}
 						} else {
 							fmt.Println(owner, method, res, "call", res.Fun, reflect.TypeOf(res.Fun))
 						}
 					default:
-						fmt.Println(owner, method, res, reflect.TypeOf(res))
+						fmt.Println(owner, method, res, reflect.TypeOf(ret.Results[0]))
 					}
 				}
 				// Insert the function to the submodule collection (alphabetically)
@@ -323,6 +373,12 @@ func generate(methods map[string][]*Endpoint) ([]byte, error) {
 
 				if endpoint.Return == "int64" {
 					client += fmt.Sprintf("return new(big.Int).SetBytes(common.FromHex(res.(string))).Int64(), nil\n")
+				} else if endpoint.Return == "*big.Int" {
+					client += fmt.Sprintf("return new(big.Int).SetBytes(common.FromHex(res.(string))), nil\n")
+				} else if endpoint.Return == "[]byte" {
+					client += fmt.Sprintf("return res.([]byte), nil\n")
+				} else if strings.HasPrefix(endpoint.Return, "[]") {
+					client += fmt.Sprintf("for _, item := range res.([]interface{}) { result = append(result, item.(%s))}; return\n", endpoint.Return[2:])
 				} else {
 					client += fmt.Sprintf("return res.(%s), nil\n", endpoint.Return)
 				}