internal/testlog, log: add Inner method to log.Logger to expose wrapped slog.Logger. fix log.SetDefault to also set slog default logger.

internal/testlog/testlog.go

@@ -98,8 +98,8 @@ func LoggerWithHandler(t *testing.T, handler slog.Handler) log.Logger {
 	}
 }
 
-func (l *logger) Handler() slog.Handler {
-	return l.l.Handler()
+func (l *logger) Inner() *slog.Logger {
+	return l.l.Inner()
 }
 
 func (l *logger) Trace(msg string, ctx ...interface{}) {

log/logger.go

@@ -105,9 +105,6 @@ func LevelString(l slog.Level) string {
 
 // A Logger writes key/value pairs to a Handler
 type Logger interface {
-	// Handler returns the handler associated with this logger
-	Handler() slog.Handler
-
 	// TODO: add WithGroup()?
 
 	// With returns a new Logger that has this logger's attributes plus the given attributes
@@ -136,6 +133,9 @@ type Logger interface {
 
 	// Crit logs a message at the crit level with context key/value pairs, and exits
 	Crit(msg string, ctx ...interface{})
+
+	// Inner returns the underlying slog logger that is wrapped
+	Inner() *slog.Logger
 }
 
 type logger struct {
@@ -149,8 +149,9 @@ func NewLogger(h slog.Handler) Logger {
 	}
 }
 
-func (l *logger) Handler() slog.Handler {
-	return l.inner.Handler()
+// Inner returns the underlying slog logger that 
+func (l *logger) Inner() *slog.Logger {
+	return l.inner
 }
 
 // write logs a message at the specified level:

log/root.go

@@ -2,22 +2,26 @@ package log
 
 import (
 	"os"
-	"sync/atomic"
+	"sync"
 
 	"golang.org/x/exp/slog"
 )
 
 var (
-	root = new(atomic.Value)
+	rootMu sync.Mutex
+	root logger
 )
 
 func init() {
 	defaultLogger := &logger{slog.New(DiscardHandler())}
-	root.Store(defaultLogger)
+	SetDefault(defaultLogger)
 }
 
 func SetDefault(l Logger) {
-	root.Store(l)
+	rootMu.Lock()
+	defer rootMu.Unlock()
+	root := l
+	slog.SetDefault(root.Inner())
 }
 
 // Root returns the root logger
@@ -26,8 +30,10 @@ func Root() Logger {
 }
 
 func rootLogger() *logger {
-	res, _ := root.Load().(*logger)
-	return res
+	rootMu.Lock()
+	defer rootMu.Unlock()
+	res := root
+	return &res
 }
 
 // The following functions bypass the exported logger methods (logger.Debug,