dynamic: add one more test case

Author: c9s

pkg/dynamic/metric_test.go

@@ -23,16 +23,30 @@ func TestInitializeConfigMetrics(t *testing.T) {
 		ignoredFieldInt int
 	}
 
-	metricNames, err := initializeConfigMetricsWithFieldPrefix("test", "test-01", "", &Foo{
-		MinMarginLevel: Number(1.4),
-		Bar: &Bar{
-			Enabled: true,
-		},
+	t.Run("general", func(t *testing.T) {
+		metricNames, err := initializeConfigMetricsWithFieldPrefix("test", "test-01", "", &Foo{
+			MinMarginLevel: Number(1.4),
+			Bar: &Bar{
+				Enabled: true,
+			},
+		})
+
+		if assert.NoError(t, err) {
+			assert.Len(t, metricNames, 2)
+			assert.Equal(t, "test_config_min_margin_level", metricNames[0])
+			assert.Equal(t, "test_config_bar_enabled", metricNames[1], "nested struct field as a metric")
+		}
+	})
+
+	t.Run("nil struct field", func(t *testing.T) {
+		metricNames, err := initializeConfigMetricsWithFieldPrefix("test", "test-01", "", &Foo{
+			MinMarginLevel: Number(1.4),
+		})
+
+		if assert.NoError(t, err) {
+			assert.Len(t, metricNames, 1)
+			assert.Equal(t, "test_config_min_margin_level", metricNames[0])
+		}
 	})
 
-	if assert.NoError(t, err) {
-		assert.Len(t, metricNames, 2)
-		assert.Equal(t, "test_config_min_margin_level", metricNames[0])
-		assert.Equal(t, "test_config_bar_enabled", metricNames[1], "nested struct field as a metric")
-	}
 }