leveled: fix default logger and add a test

leveled/logger.go

@@ -41,30 +41,30 @@ func Default(logger *alog.Logger) Logger {
 
 // Debug implements Logger.Debug
 func (d *defaultLogger) Debug(ctx context.Context, f string, v ...interface{}) {
-	alog.AddTags(ctx, "level", "debug")
+	ctx = alog.AddTags(ctx, "level", "debug")
 	d.Logger.Output(ctx, 3, fmt.Sprintf(f, v...))
 }
 
 // Info implements Logger.Info
 func (d *defaultLogger) Info(ctx context.Context, f string, v ...interface{}) {
-	alog.AddTags(ctx, "level", "info")
+	ctx = alog.AddTags(ctx, "level", "info")
 	d.Logger.Output(ctx, 3, fmt.Sprintf(f, v...))
 }
 
 // Warning implements Logger.Warning
 func (d *defaultLogger) Warning(ctx context.Context, f string, v ...interface{}) {
-	alog.AddTags(ctx, "level", "warning")
+	ctx = alog.AddTags(ctx, "level", "warning")
 	d.Logger.Output(ctx, 3, fmt.Sprintf(f, v...))
 }
 
 // Error implements Logger.Error
 func (d *defaultLogger) Error(ctx context.Context, f string, v ...interface{}) {
-	alog.AddTags(ctx, "level", "error")
+	ctx = alog.AddTags(ctx, "level", "error")
 	d.Logger.Output(ctx, 3, fmt.Sprintf(f, v...))
 }
 
 // Critical implements Logger.Critical
 func (d *defaultLogger) Critical(ctx context.Context, f string, v ...interface{}) {
-	alog.AddTags(ctx, "level", "critical")
+	ctx = alog.AddTags(ctx, "level", "critical")
 	d.Logger.Output(ctx, 3, fmt.Sprintf(f, v...))
 }

leveled/logger_test.go

@@ -0,0 +1,23 @@
+package leveled
+
+import (
+	"bytes"
+	"context"
+	"testing"
+
+	"github.com/vimeo/alog/v3"
+	"github.com/vimeo/alog/v3/emitter/textlog"
+)
+
+func TestLogger(t *testing.T) {
+	b := &bytes.Buffer{}
+	l := Default(alog.New(alog.WithEmitter(textlog.Emitter(b))))
+
+	ctx := context.Background()
+	ctx = alog.AddTags(ctx, "key", "value")
+	l.Info(ctx, "")
+	const want = `[key=value level=info] ` + "\n"
+	if got := b.String(); got != want {
+		t.Errorf("got: %#q, want: %#q", got, want)
+	}
+}