// Use of this source code is governed by a BSD-style license that can be// found in the LICENSE file.import'package:flutter/material.dart';import'package:flutter_test/flutter_test.dart';import'package:quiver/testing/async.dart';voidmain(){setUp((){WidgetsFlutterBinding.ensureInitialized();WidgetsBinding.instance.resetEpoch();});test('WidgetBinding build rendering tree and warm up frame back to back',(){finalFakeAsyncfakeAsync=FakeAsync();fakeAsync.run((FakeAsyncasync){runApp(constMaterialApp(home:Material(child:Text('test'),),),);// Rendering tree is not built synchronously.expect(WidgetsBinding.instance.renderViewElement,isNull);fakeAsync.flushTimers();expect(WidgetsBinding.instance.renderViewElement,isNotNull);});});}