Merge 20c22d9 into 2039c56

js/modules/k6/metrics/metrics.go

@@ -65,7 +65,16 @@ func newMetric(ctxPtr *context.Context, name string, t stats.MetricType, isTime
 	}
 
 	rt := common.GetRuntime(*ctxPtr)
-	return common.Bind(rt, Metric{stats.New(name, t, valueType)}, ctxPtr), nil
+	bound := common.Bind(rt, Metric{stats.New(name, t, valueType)}, ctxPtr)
+	o := rt.NewObject()
+	err := o.DefineDataProperty("name", rt.ToValue(name), goja.FLAG_FALSE, goja.FLAG_FALSE, goja.FLAG_TRUE)
+	if err != nil {
+		return nil, err
+	}
+	if err = o.Set("add", rt.ToValue(bound["add"])); err != nil {
+		return nil, err
+	}
+	return o, nil
 }
 
 func (m Metric) Add(ctx context.Context, v goja.Value, addTags ...map[string]string) (bool, error) {
@@ -91,11 +100,6 @@ func (m Metric) Add(ctx context.Context, v goja.Value, addTags ...map[string]str
 	return true, nil
 }
 
-// GetName returns the metric name
-func (m Metric) GetName() string {
-	return m.metric.Name
-}
-
 type Metrics struct{}
 
 func New() *Metrics {

js/modules/k6/metrics/metrics_test.go

@@ -172,6 +172,23 @@ func TestMetricNames(t *testing.T) {
 
 func TestMetricGetName(t *testing.T) {
 	t.Parallel()
-	metric := Metric{metric: &stats.Metric{Name: "myMetricName"}}
-	assert.Equal(t, "myMetricName", metric.GetName())
+	rt := goja.New()
+	rt.SetFieldNameMapper(common.FieldNameMapper{})
+
+	ctxPtr := new(context.Context)
+	*ctxPtr = common.WithRuntime(context.Background(), rt)
+	require.NoError(t, rt.Set("metrics", common.Bind(rt, New(), ctxPtr)))
+	v, err := rt.RunString(`
+		var m = new metrics.Counter("my_metric")
+		m.name
+	`)
+	require.NoError(t, err)
+	require.Equal(t, "my_metric", v.String())
+
+	_, err = rt.RunString(`
+		"use strict";
+		m.name = "something"
+	`)
+	require.Error(t, err)
+	require.Contains(t, err.Error(), "TypeError: Cannot assign to read only property 'name'")
 }

samples/custom_metrics.js

@@ -28,7 +28,7 @@ export default function () {
 
     // Add one for number of requests
     myCounter.add(1);
-    console.log(myCounter.getName(), " is config ready")
+    console.log(myCounter.name, " is config ready")
 
     // Set max response time seen
     maxResponseTime = Math.max(maxResponseTime, res.timings.duration);