Introduce RunES6String and replace RunString to not support ES6

this should again lower the amount of time test take for close to zero
additional scripting.

js/common/bridge_test.go

@@ -324,23 +324,23 @@ func TestBind(t *testing.T) {
 		{"Methods", bridgeTestMethodsType{}, func(t *testing.T, obj interface{}, rt *goja.Runtime) {
 			t.Run("unexportedFn", func(t *testing.T) {
 				_, err := RunString(rt, `obj.unexportedFn()`)
-				assert.EqualError(t, err, "TypeError: Object has no member 'unexportedFn' at <eval>:1:30(3)")
+				assert.EqualError(t, err, "TypeError: Object has no member 'unexportedFn' at <eval>:1:17(3)")
 			})
 			t.Run("ExportedFn", func(t *testing.T) {
 				_, err := RunString(rt, `obj.exportedFn()`)
 				assert.NoError(t, err)
 			})
 			t.Run("unexportedPtrFn", func(t *testing.T) {
 				_, err := RunString(rt, `obj.unexportedPtrFn()`)
-				assert.EqualError(t, err, "TypeError: Object has no member 'unexportedPtrFn' at <eval>:1:33(3)")
+				assert.EqualError(t, err, "TypeError: Object has no member 'unexportedPtrFn' at <eval>:1:20(3)")
 			})
 			t.Run("ExportedPtrFn", func(t *testing.T) {
 				_, err := RunString(rt, `obj.exportedPtrFn()`)
 				switch obj.(type) {
 				case *bridgeTestMethodsType:
 					assert.NoError(t, err)
 				case bridgeTestMethodsType:
-					assert.EqualError(t, err, "TypeError: Object has no member 'exportedPtrFn' at <eval>:1:31(3)")
+					assert.EqualError(t, err, "TypeError: Object has no member 'exportedPtrFn' at <eval>:1:18(3)")
 				default:
 					assert.Fail(t, "INVALID TYPE")
 				}
@@ -527,7 +527,7 @@ func TestBind(t *testing.T) {
 			_, err := RunString(rt, `obj.contextInject()`)
 			switch impl := obj.(type) {
 			case bridgeTestContextInjectType:
-				assert.EqualError(t, err, "TypeError: Object has no member 'contextInject' at <eval>:1:31(3)")
+				assert.EqualError(t, err, "TypeError: Object has no member 'contextInject' at <eval>:1:18(3)")
 			case *bridgeTestContextInjectType:
 				assert.EqualError(t, err, "GoError: contextInject() can only be called from within default()")
 				assert.Equal(t, nil, impl.ctx)
@@ -546,7 +546,7 @@ func TestBind(t *testing.T) {
 			_, err := RunString(rt, `obj.contextInjectPtr()`)
 			switch impl := obj.(type) {
 			case bridgeTestContextInjectPtrType:
-				assert.EqualError(t, err, "TypeError: Object has no member 'contextInjectPtr' at <eval>:1:34(3)")
+				assert.EqualError(t, err, "TypeError: Object has no member 'contextInjectPtr' at <eval>:1:21(3)")
 			case *bridgeTestContextInjectPtrType:
 				assert.NoError(t, err)
 				assert.Equal(t, ctxPtr, impl.ctxPtr)
@@ -566,7 +566,7 @@ func TestBind(t *testing.T) {
 				}
 			case bridgeTestCounterType:
 				_, err := RunString(rt, `obj.count()`)
-				assert.EqualError(t, err, "TypeError: Object has no member 'count' at <eval>:1:23(3)")
+				assert.EqualError(t, err, "TypeError: Object has no member 'count' at <eval>:1:10(3)")
 			default:
 				assert.Fail(t, "UNKNOWN TYPE")
 			}

js/common/util.go

@@ -25,15 +25,20 @@ import (
 	"github.com/loadimpact/k6/js/compiler"
 )
 
-// Runs an ES6 string in the given runtime. Use this rather than writing ES5 in tests.
+// RunString Runs an string in the given runtime. Use this if writing ES5 in tests isn't a problem.
 func RunString(rt *goja.Runtime, src string) (goja.Value, error) {
+	return rt.RunString(src)
+}
+
+// RunES6String Runs an ES6 string in the given runtime. Use this rather than writing ES5 in tests.
+func RunES6String(rt *goja.Runtime, src string) (goja.Value, error) {
 	var err error
 	c := compiler.New()
 	src, _, err = c.Transform(src, "__string__")
 	if err != nil {
 		return goja.Undefined(), err
 	}
-	return rt.RunString(src)
+	return RunString(rt, src)
 }
 
 // Throws a JS error; avoids re-wrapping GoErrors.

js/common/util_test.go

@@ -30,11 +30,11 @@ import (
 
 func TestRunString(t *testing.T) {
 	t.Run("Valid", func(t *testing.T) {
-		_, err := RunString(goja.New(), `let a = 1;`)
+		_, err := RunES6String(goja.New(), `let a = 1;`)
 		assert.NoError(t, err)
 	})
 	t.Run("Invalid", func(t *testing.T) {
-		_, err := RunString(goja.New(), `let a = #;`)
+		_, err := RunES6String(goja.New(), `let a = #;`)
 		assert.NotNil(t, err)
 		assert.Contains(t, err.Error(), "SyntaxError: __string__: Unexpected character '#' (1:8)\n> 1 | let a = #;\n")
 	})