From 02c22427916ff8243c609a0b0b5bbe934c3dbf35 Mon Sep 17 00:00:00 2001
From: ferhat elmas <elmas.ferhat@gmail.com>
Date: Fri, 17 Nov 2017 03:16:29 +0100
Subject: [PATCH] build: enable deadcode linter

 * also fixes warnings generated by linter
 * fixes #15473
---
 accounts/abi/numbers.go            |  1 +
 accounts/usbwallet/ledger.go       |  1 +
 build/ci.go                        |  9 ++++++++-
 consensus/clique/clique.go         |  1 +
 consensus/ethash/algorithm.go      |  1 +
 core/asm/compiler.go               |  1 +
 core/chain_makers.go               |  2 ++
 core/genesis.go                    |  1 +
 core/tx_pool.go                    |  1 +
 core/types/block.go                |  1 +
 core/types/log.go                  |  1 +
 core/types/receipt.go              |  1 +
 core/types/transaction.go          |  2 ++
 core/vm/logger.go                  |  1 +
 core/vm/memory_table.go            |  6 ------
 crypto/sha3/xor.go                 |  1 +
 crypto/sha3/xor_unaligned.go       |  1 +
 eth/config.go                      |  1 +
 eth/downloader/downloader.go       |  1 +
 les/bloombits.go                   |  1 +
 les/serverpool.go                  |  1 +
 les/sync.go                        |  1 +
 p2p/discover/node.go               |  1 +
 p2p/discover/udp.go                |  1 +
 p2p/discv5/net.go                  |  7 ++++---
 p2p/discv5/node.go                 |  1 +
 p2p/discv5/nodeevent_string.go     | 13 +++++++------
 p2p/discv5/ntp.go                  |  1 +
 p2p/discv5/table.go                |  1 +
 p2p/discv5/udp.go                  |  2 ++
 p2p/message.go                     |  1 +
 p2p/peer.go                        |  1 +
 p2p/server.go                      |  1 +
 swarm/network/kademlia/kademlia.go |  1 +
 swarm/storage/dbstore.go           |  1 +
 swarm/storage/netstore.go          |  1 +
 whisper/whisperv2/topic.go         |  2 ++
 37 files changed, 56 insertions(+), 16 deletions(-)

diff --git a/accounts/abi/numbers.go b/accounts/abi/numbers.go
index 9ad99f90d2..c8f4872dc0 100644
--- a/accounts/abi/numbers.go
+++ b/accounts/abi/numbers.go
@@ -50,6 +50,7 @@ func U256(n *big.Int) []byte {
 }
 
 // checks whether the given reflect value is signed. This also works for slices with a number type
+// nolint: deadcode
 func isSigned(v reflect.Value) bool {
 	switch v.Type() {
 	case int_ts, int8_ts, int16_ts, int32_ts, int64_ts, int_t, int8_t, int16_t, int32_t, int64_t:
diff --git a/accounts/usbwallet/ledger.go b/accounts/usbwallet/ledger.go
index f5def61d23..4bb341e504 100644
--- a/accounts/usbwallet/ledger.go
+++ b/accounts/usbwallet/ledger.go
@@ -47,6 +47,7 @@ type ledgerParam1 byte
 // specific opcodes. The same parameter values may be reused between opcodes.
 type ledgerParam2 byte
 
+// nolint: deadcode
 const (
 	ledgerOpRetrieveAddress  ledgerOpcode = 0x02 // Returns the public key and Ethereum address for a given BIP 32 path
 	ledgerOpSignTransaction  ledgerOpcode = 0x04 // Signs an Ethereum transaction after having the user validate the parameters
diff --git a/build/ci.go b/build/ci.go
index 0c825ef31e..78dddb95a5 100644
--- a/build/ci.go
+++ b/build/ci.go
@@ -323,7 +323,14 @@ func doLint(cmdline []string) {
 	build.MustRunCommand(filepath.Join(GOBIN, "gometalinter.v1"), "--install")
 
 	// Run fast linters batched together
-	configs := []string{"--vendor", "--disable-all", "--enable=vet", "--enable=gofmt", "--enable=misspell"}
+	configs := []string{"--vendor", "-t",
+		"--disable-all",
+		"--exclude=cmd/faucet/website.go",
+		"--enable=vet",
+		"--enable=gofmt",
+		"--enable=misspell",
+		"--enable=deadcode",
+	}
 	build.MustRunCommand(filepath.Join(GOBIN, "gometalinter.v1"), append(configs, packages...)...)
 
 	// Run slow linters one by one
diff --git a/consensus/clique/clique.go b/consensus/clique/clique.go
index 6892d83906..c98b11c7a7 100644
--- a/consensus/clique/clique.go
+++ b/consensus/clique/clique.go
@@ -51,6 +51,7 @@ const (
 )
 
 // Clique proof-of-authority protocol constants.
+// nolint: deadcode
 var (
 	epochLength = uint64(30000) // Default number of blocks after which to checkpoint and reset the pending votes
 	blockPeriod = uint64(15)    // Default minimum difference between two consecutive block's timestamps
diff --git a/consensus/ethash/algorithm.go b/consensus/ethash/algorithm.go
index 76f19252fa..4d3880966e 100644
--- a/consensus/ethash/algorithm.go
+++ b/consensus/ethash/algorithm.go
@@ -163,6 +163,7 @@ func swap(buffer []byte) {
 // prepare converts an ethash cache or dataset from a byte stream into the internal
 // int representation. All ethash methods work with ints to avoid constant byte to
 // int conversions as well as to handle both little and big endian systems.
+// nolint: deadcode
 func prepare(dest []uint32, src []byte) {
 	for i := 0; i < len(dest); i++ {
 		dest[i] = binary.LittleEndian.Uint32(src[i*4:])
diff --git a/core/asm/compiler.go b/core/asm/compiler.go
index b2c85375cc..41b4311331 100644
--- a/core/asm/compiler.go
+++ b/core/asm/compiler.go
@@ -267,6 +267,7 @@ func (err compileError) Error() string {
 	return fmt.Sprintf("%d syntax error: unexpected %v, expected %v", err.lineno, err.got, err.want)
 }
 
+// nolint: deadcode
 var (
 	errExpBol            = errors.New("expected beginning of line")
 	errExpElementOrLabel = errors.New("expected beginning of line")
diff --git a/core/chain_makers.go b/core/chain_makers.go
index 59af633dfd..35f79f6dab 100644
--- a/core/chain_makers.go
+++ b/core/chain_makers.go
@@ -31,6 +31,7 @@ import (
 )
 
 // So we can deterministically seed different blockchains
+// nolint: deadcode
 var (
 	canonicalSeed = 1
 	forkSeed      = 2
@@ -229,6 +230,7 @@ func makeHeader(config *params.ChainConfig, parent *types.Block, state *state.St
 // newCanonical creates a chain database, and injects a deterministic canonical
 // chain. Depending on the full flag, if creates either a full block chain or a
 // header only chain.
+// nolint: deadcode
 func newCanonical(n int, full bool) (ethdb.Database, *BlockChain, error) {
 	// Initialize a fresh chain with only a genesis block
 	gspec := new(Genesis)
diff --git a/core/genesis.go b/core/genesis.go
index df491ce0f4..d4f38f1b60 100644
--- a/core/genesis.go
+++ b/core/genesis.go
@@ -86,6 +86,7 @@ type GenesisAccount struct {
 }
 
 // field type overrides for gencodec
+// nolint: deadcode
 type genesisSpecMarshaling struct {
 	Nonce      math.HexOrDecimal64
 	Timestamp  math.HexOrDecimal64
diff --git a/core/tx_pool.go b/core/tx_pool.go
index c3915575b0..f42a622f31 100644
--- a/core/tx_pool.go
+++ b/core/tx_pool.go
@@ -35,6 +35,7 @@ import (
 	"gopkg.in/karalabe/cookiejar.v2/collections/prque"
 )
 
+// nolint: deadcode
 const (
 	// chainHeadChanSize is the size of channel listening to ChainHeadEvent.
 	chainHeadChanSize = 10
diff --git a/core/types/block.go b/core/types/block.go
index 1d00d9f930..c1303eb9b4 100644
--- a/core/types/block.go
+++ b/core/types/block.go
@@ -86,6 +86,7 @@ type Header struct {
 }
 
 // field type overrides for gencodec
+// nolint: deadcode
 type headerMarshaling struct {
 	Difficulty *hexutil.Big
 	Number     *hexutil.Big
diff --git a/core/types/log.go b/core/types/log.go
index be5de38da7..bd80e6f68b 100644
--- a/core/types/log.go
+++ b/core/types/log.go
@@ -56,6 +56,7 @@ type Log struct {
 	Removed bool `json:"removed"`
 }
 
+// nolint: deadcode
 type logMarshaling struct {
 	Data        hexutil.Bytes
 	BlockNumber hexutil.Uint64
diff --git a/core/types/receipt.go b/core/types/receipt.go
index bc3c996b4f..f21407d14e 100644
--- a/core/types/receipt.go
+++ b/core/types/receipt.go
@@ -57,6 +57,7 @@ type Receipt struct {
 	GasUsed         *big.Int       `json:"gasUsed" gencodec:"required"`
 }
 
+// nolint: deadcode
 type receiptMarshaling struct {
 	PostState         hexutil.Bytes
 	Status            hexutil.Uint
diff --git a/core/types/transaction.go b/core/types/transaction.go
index a46521236c..70460e87c4 100644
--- a/core/types/transaction.go
+++ b/core/types/transaction.go
@@ -32,6 +32,7 @@ import (
 
 //go:generate gencodec -type txdata -field-override txdataMarshaling -out gen_tx_json.go
 
+// nolint: deadcode
 var (
 	ErrInvalidSig = errors.New("invalid transaction v, r, s values")
 	errNoSigner   = errors.New("missing signing methods")
@@ -71,6 +72,7 @@ type txdata struct {
 	Hash *common.Hash `json:"hash" rlp:"-"`
 }
 
+// nolint: deadcode
 type txdataMarshaling struct {
 	AccountNonce hexutil.Uint64
 	Price        *hexutil.Big
diff --git a/core/vm/logger.go b/core/vm/logger.go
index 75309da921..ba54686e9a 100644
--- a/core/vm/logger.go
+++ b/core/vm/logger.go
@@ -66,6 +66,7 @@ type StructLog struct {
 }
 
 // overrides for gencodec
+// nolint: deadcode
 type structLogMarshaling struct {
 	Stack   []*math.HexOrDecimal256
 	Gas     math.HexOrDecimal64
diff --git a/core/vm/memory_table.go b/core/vm/memory_table.go
index bec0235bcc..ab49ebb38b 100644
--- a/core/vm/memory_table.go
+++ b/core/vm/memory_table.go
@@ -65,12 +65,6 @@ func memoryCall(stack *Stack) *big.Int {
 	return math.BigMax(x, y)
 }
 
-func memoryCallCode(stack *Stack) *big.Int {
-	x := calcMemSize(stack.Back(5), stack.Back(6))
-	y := calcMemSize(stack.Back(3), stack.Back(4))
-
-	return math.BigMax(x, y)
-}
 func memoryDelegateCall(stack *Stack) *big.Int {
 	x := calcMemSize(stack.Back(4), stack.Back(5))
 	y := calcMemSize(stack.Back(2), stack.Back(3))
diff --git a/crypto/sha3/xor.go b/crypto/sha3/xor.go
index 46a0d63a6d..df6cd3896e 100644
--- a/crypto/sha3/xor.go
+++ b/crypto/sha3/xor.go
@@ -13,4 +13,5 @@ var (
 	copyOutUnaligned = copyOutGeneric
 )
 
+// nolint: deadcode
 const xorImplementationUnaligned = "generic"
diff --git a/crypto/sha3/xor_unaligned.go b/crypto/sha3/xor_unaligned.go
index 929a486a79..608e994984 100644
--- a/crypto/sha3/xor_unaligned.go
+++ b/crypto/sha3/xor_unaligned.go
@@ -55,4 +55,5 @@ var (
 	copyOut = copyOutUnaligned
 )
 
+// nolint: deadcode
 const xorImplementationUnaligned = "unaligned"
diff --git a/eth/config.go b/eth/config.go
index 7bcfd403ea..f6c610a081 100644
--- a/eth/config.go
+++ b/eth/config.go
@@ -115,6 +115,7 @@ type Config struct {
 	PowShared bool   `toml:"-"`
 }
 
+// nolint: deadcode
 type configMarshaling struct {
 	ExtraData hexutil.Bytes
 }
diff --git a/eth/downloader/downloader.go b/eth/downloader/downloader.go
index b338129e00..193cd3f830 100644
--- a/eth/downloader/downloader.go
+++ b/eth/downloader/downloader.go
@@ -69,6 +69,7 @@ var (
 	fsCriticalTrials       = uint32(32) // Number of times to retry in the cricical section before bailing
 )
 
+// nolint: deadcode
 var (
 	errBusy                    = errors.New("busy")
 	errUnknownPeer             = errors.New("peer is unknown or unhealthy")
diff --git a/les/bloombits.go b/les/bloombits.go
index de233d7518..9453e25126 100644
--- a/les/bloombits.go
+++ b/les/bloombits.go
@@ -73,6 +73,7 @@ func (eth *LightEthereum) startBloomHandlers() {
 	}
 }
 
+// nolint: deadcode
 const (
 	// bloomConfirms is the number of confirmation blocks before a bloom section is
 	// considered probably final and its rotated bits are calculated.
diff --git a/les/serverpool.go b/les/serverpool.go
index dc1ea6bf02..22c5d21467 100644
--- a/les/serverpool.go
+++ b/les/serverpool.go
@@ -36,6 +36,7 @@ import (
 	"github.com/ethereum/go-ethereum/rlp"
 )
 
+// nolint: deadcode
 const (
 	// After a connection has been ended or timed out, there is a waiting period
 	// before it can be selected for connection again.
diff --git a/les/sync.go b/les/sync.go
index c0e17f97d9..43d613413a 100644
--- a/les/sync.go
+++ b/les/sync.go
@@ -25,6 +25,7 @@ import (
 	"github.com/ethereum/go-ethereum/light"
 )
 
+// nolint: deadcode
 const (
 	//forceSyncCycle      = 10 * time.Second // Time interval to force syncs, even if few peers are available
 	minDesiredPeerCount = 5 // Amount of peers desired to start syncing
diff --git a/p2p/discover/node.go b/p2p/discover/node.go
index fc928a91af..877e9f8542 100644
--- a/p2p/discover/node.go
+++ b/p2p/discover/node.go
@@ -412,6 +412,7 @@ func logdist(a, b common.Hash) int {
 }
 
 // hashAtDistance returns a random hash such that logdist(a, b) == n
+// nolint: deadcode
 func hashAtDistance(a common.Hash, n int) (b common.Hash) {
 	if n == 0 {
 		return a
diff --git a/p2p/discover/udp.go b/p2p/discover/udp.go
index f9eb99ee36..cc9462b410 100644
--- a/p2p/discover/udp.go
+++ b/p2p/discover/udp.go
@@ -47,6 +47,7 @@ var (
 )
 
 // Timeouts
+// nolint: deadcode
 const (
 	respTimeout = 500 * time.Millisecond
 	sendTimeout = 500 * time.Millisecond
diff --git a/p2p/discv5/net.go b/p2p/discv5/net.go
index a39cfcc645..bb545068bd 100644
--- a/p2p/discv5/net.go
+++ b/p2p/discv5/net.go
@@ -34,6 +34,7 @@ import (
 	"github.com/ethereum/go-ethereum/rlp"
 )
 
+// nolint: deadcode
 var (
 	errInvalidEvent = errors.New("invalid in current state")
 	errNoQuery      = errors.New("no pending query")
@@ -48,6 +49,7 @@ const (
 	lowPort               = 1024
 )
 
+// nolint: deadcode
 const testTopic = "foo"
 
 const (
@@ -825,12 +827,11 @@ type nodeEvent uint
 
 //go:generate stringer -type=nodeEvent
 
+//
 const (
-	invalidEvent nodeEvent = iota // zero is reserved
-
 	// Packet type events.
 	// These correspond to packet types in the UDP protocol.
-	pingPacket
+	pingPacket nodeEvent = iota + 1
 	pongPacket
 	findnodePacket
 	neighborsPacket
diff --git a/p2p/discv5/node.go b/p2p/discv5/node.go
index 2db7a508f0..0d0d03e89e 100644
--- a/p2p/discv5/node.go
+++ b/p2p/discv5/node.go
@@ -413,6 +413,7 @@ func logdist(a, b common.Hash) int {
 }
 
 // hashAtDistance returns a random hash such that logdist(a, b) == n
+// nolint: deadcode
 func hashAtDistance(a common.Hash, n int) (b common.Hash) {
 	if n == 0 {
 		return a
diff --git a/p2p/discv5/nodeevent_string.go b/p2p/discv5/nodeevent_string.go
index fde9045c52..02b74e3f63 100644
--- a/p2p/discv5/nodeevent_string.go
+++ b/p2p/discv5/nodeevent_string.go
@@ -1,25 +1,26 @@
-// Code generated by "stringer -type nodeEvent"; DO NOT EDIT
+// Code generated by "stringer -type=nodeEvent"; DO NOT EDIT.
 
 package discv5
 
 import "fmt"
 
 const (
-	_nodeEvent_name_0 = "invalidEventpingPacketpongPacketfindnodePacketneighborsPacketfindnodeHashPackettopicRegisterPackettopicQueryPackettopicNodesPacket"
+	_nodeEvent_name_0 = "pingPacketpongPacketfindnodePacketneighborsPacketfindnodeHashPackettopicRegisterPackettopicQueryPackettopicNodesPacket"
 	_nodeEvent_name_1 = "pongTimeoutpingTimeoutneighboursTimeout"
 )
 
 var (
-	_nodeEvent_index_0 = [...]uint8{0, 12, 22, 32, 46, 61, 79, 98, 114, 130}
+	_nodeEvent_index_0 = [...]uint8{0, 10, 20, 34, 49, 67, 86, 102, 118}
 	_nodeEvent_index_1 = [...]uint8{0, 11, 22, 39}
 )
 
 func (i nodeEvent) String() string {
 	switch {
-	case 0 <= i && i <= 8:
+	case 1 <= i && i <= 8:
+		i -= 1
 		return _nodeEvent_name_0[_nodeEvent_index_0[i]:_nodeEvent_index_0[i+1]]
-	case 265 <= i && i <= 267:
-		i -= 265
+	case 264 <= i && i <= 266:
+		i -= 264
 		return _nodeEvent_name_1[_nodeEvent_index_1[i]:_nodeEvent_index_1[i+1]]
 	default:
 		return fmt.Sprintf("nodeEvent(%d)", i)
diff --git a/p2p/discv5/ntp.go b/p2p/discv5/ntp.go
index f78d5dc43c..3da4251533 100644
--- a/p2p/discv5/ntp.go
+++ b/p2p/discv5/ntp.go
@@ -44,6 +44,7 @@ func (s durationSlice) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
 
 // checkClockDrift queries an NTP server for clock drifts and warns the user if
 // one large enough is detected.
+// nolint: deadcode
 func checkClockDrift() {
 	drift, err := sntpDrift(ntpChecks)
 	if err != nil {
diff --git a/p2p/discv5/table.go b/p2p/discv5/table.go
index 2cf05009cb..5b4788972c 100644
--- a/p2p/discv5/table.go
+++ b/p2p/discv5/table.go
@@ -32,6 +32,7 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 )
 
+// nolint: deadcode
 const (
 	alpha      = 3  // Kademlia concurrency factor
 	bucketSize = 16 // Kademlia bucket size
diff --git a/p2p/discv5/udp.go b/p2p/discv5/udp.go
index 26087cd8e5..22ffa7aa50 100644
--- a/p2p/discv5/udp.go
+++ b/p2p/discv5/udp.go
@@ -35,6 +35,7 @@ import (
 const Version = 4
 
 // Errors
+// nolint: deadcode
 var (
 	errPacketTooSmall   = errors.New("too small")
 	errBadHash          = errors.New("bad hash")
@@ -47,6 +48,7 @@ var (
 )
 
 // Timeouts
+// nolint: deadcode
 const (
 	respTimeout = 500 * time.Millisecond
 	sendTimeout = 500 * time.Millisecond
diff --git a/p2p/message.go b/p2p/message.go
index 5690494bf4..1e9006279f 100644
--- a/p2p/message.go
+++ b/p2p/message.go
@@ -114,6 +114,7 @@ func SendItems(w MsgWriter, msgcode uint64, elems ...interface{}) error {
 
 // netWrapper wraps a MsgReadWriter with locks around
 // ReadMsg/WriteMsg and applies read/write deadlines.
+// nolint: deadcode
 type netWrapper struct {
 	rmu, wmu sync.Mutex
 
diff --git a/p2p/peer.go b/p2p/peer.go
index 1d2b726e8b..1d67b61b85 100644
--- a/p2p/peer.go
+++ b/p2p/peer.go
@@ -41,6 +41,7 @@ const (
 	pingInterval = 15 * time.Second
 )
 
+// nolint: deadcode
 const (
 	// devp2p message codes
 	handshakeMsg = 0x00
diff --git a/p2p/server.go b/p2p/server.go
index d1d578401b..750cdf9947 100644
--- a/p2p/server.go
+++ b/p2p/server.go
@@ -35,6 +35,7 @@ import (
 	"github.com/ethereum/go-ethereum/p2p/netutil"
 )
 
+// nolint: deadcode
 const (
 	defaultDialTimeout      = 15 * time.Second
 	refreshPeersInterval    = 30 * time.Second
diff --git a/swarm/network/kademlia/kademlia.go b/swarm/network/kademlia/kademlia.go
index bf976a3e1d..b2a5a98b05 100644
--- a/swarm/network/kademlia/kademlia.go
+++ b/swarm/network/kademlia/kademlia.go
@@ -307,6 +307,7 @@ type nodesByDistance struct {
 	target Address
 }
 
+// nolint: deadcode
 func sortedByDistanceTo(target Address, slice []Node) bool {
 	var last Address
 	for i, node := range slice {
diff --git a/swarm/storage/dbstore.go b/swarm/storage/dbstore.go
index 46a5c16ccc..7578697789 100644
--- a/swarm/storage/dbstore.go
+++ b/swarm/storage/dbstore.go
@@ -38,6 +38,7 @@ import (
 	"github.com/syndtr/goleveldb/leveldb/iterator"
 )
 
+// nolint: deadcode
 const (
 	defaultDbCapacity = 5000000
 	defaultRadius     = 0 // not yet used
diff --git a/swarm/storage/netstore.go b/swarm/storage/netstore.go
index 7b0612edc5..c7cbd8cb0e 100644
--- a/swarm/storage/netstore.go
+++ b/swarm/storage/netstore.go
@@ -77,6 +77,7 @@ func NewNetStore(hash SwarmHasher, lstore *LocalStore, cloud CloudStore, params
 	}
 }
 
+// nolint: deadcode
 const (
 	// maximum number of peers that a retrieved message is delivered to
 	requesterCount = 3
diff --git a/whisper/whisperv2/topic.go b/whisper/whisperv2/topic.go
index 3e2b47bd3f..5869a7e521 100644
--- a/whisper/whisperv2/topic.go
+++ b/whisper/whisperv2/topic.go
@@ -104,6 +104,7 @@ func newTopicMatcher(topics ...[]Topic) *topicMatcher {
 }
 
 // newTopicMatcherFromBinary create a topic matcher from a list of binary conditions.
+// nolint: deadcode
 func newTopicMatcherFromBinary(data ...[][]byte) *topicMatcher {
 	topics := make([][]Topic, len(data))
 	for i, condition := range data {
@@ -114,6 +115,7 @@ func newTopicMatcherFromBinary(data ...[][]byte) *topicMatcher {
 
 // newTopicMatcherFromStrings creates a topic matcher from a list of textual
 // conditions.
+// nolint: deadcode
 func newTopicMatcherFromStrings(data ...[]string) *topicMatcher {
 	topics := make([][]Topic, len(data))
 	for i, condition := range data {