Improve comments

zbark/barkify.go

@@ -65,6 +65,9 @@ func (l barker) WithError(err error) bark.Logger {
 }
 
 func (l barker) Fields() bark.Fields {
-	l.SugaredLogger.Warn("Fields() call to bark logger is not supported by Zap")
+	// Zap has already marshaled the accumulated logger context to []byte, so we
+	// can't reconstruct the original objects. To satisfy this interface, just
+	// return nil.
+	l.SugaredLogger.Warn("zap-to-bark compatibility wrapper does not support Fields method")
 	return nil
 }

zbark/barkify_test.go

@@ -111,7 +111,7 @@ func TestBarkLoggerWith(t *testing.T) {
 
 		entry := logs.All()[0]
 		assert.Equal(t,
-			"Fields() call to bark logger is not supported by Zap", entry.Message,
+			"zap-to-bark compatibility wrapper does not support Fields method", entry.Message,
 			"message did not match")
 		assert.Equal(t, zapcore.WarnLevel, entry.Level, "message level did not match")
 	})

zbark/zapify.go

@@ -28,7 +28,7 @@ import (
 
 // Zapify wraps a bark logger in a compatibility layer to produce a
 // *zap.Logger. Note that the wrapper always treats zap's DPanicLevel as an
-// error (even in production).
+// error (even in development).
 func Zapify(l bark.Logger) *zap.Logger {
 	return zap.New(&zapper{l})
 }
@@ -38,6 +38,10 @@ type zapper struct {
 }
 
 func (z *zapper) Enabled(lvl zapcore.Level) bool {
+	// Enabled allows zap to short-circuit some logging calls early, which
+	// improves performance. Since we're not sure what levels are enabled on the
+	// underlying bark logger, always return true; this hurts performance but
+	// not correctness.
 	return true
 }
 
@@ -46,6 +50,7 @@ func (z *zapper) With(fs []zapcore.Field) zapcore.Core {
 }
 
 func (z *zapper) Check(ent zapcore.Entry, ce *zapcore.CheckedEntry) *zapcore.CheckedEntry {
+	// Since Enabled is always true, there's no need to check it here.
 	return ce.AddCore(ent, z)
 }
 
@@ -69,12 +74,14 @@ func (z *zapper) Write(ent zapcore.Entry, fs []zapcore.Field) error {
 	default:
 		return fmt.Errorf("bark-to-zap compatibility wrapper got unknown level %v", ent.Level)
 	}
-	// The underlying bark logger timestamps the entry.
+	// The underlying bark logger timestamps the entry, so we can drop
+	// everything but the message.
 	logFunc(ent.Message)
 	return nil
 }
 
 func (z *zapper) Sync() error {
+	// Bark doesn't expose a way to flush buffered messages.
 	return nil
 }