Add:创建 flutter go web 版

packages/flutter_web/test/widgets/widgets_binding_test.dart

@@ -0,0 +1,157 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:typed_data';
+
+import 'package:flutter_web_test/flutter_web_test.dart';
+import 'package:flutter_web/services.dart';
+import 'package:flutter_web/widgets.dart';
+
+class MemoryPressureObserver with WidgetsBindingObserver {
+  bool sawMemoryPressure = false;
+
+  @override
+  void didHaveMemoryPressure() {
+    sawMemoryPressure = true;
+  }
+}
+
+class AppLifecycleStateObserver with WidgetsBindingObserver {
+  AppLifecycleState lifecycleState;
+
+  @override
+  void didChangeAppLifecycleState(AppLifecycleState state) {
+    lifecycleState = state;
+  }
+}
+
+class PushRouteObserver with WidgetsBindingObserver {
+  String pushedRoute;
+
+  @override
+  Future<bool> didPushRoute(String route) async {
+    pushedRoute = route;
+    return true;
+  }
+}
+
+void main() {
+  setUp(() {
+    WidgetsFlutterBinding.ensureInitialized();
+  });
+
+  testWidgets('didHaveMemoryPressure callback', (WidgetTester tester) async {
+    final MemoryPressureObserver observer = MemoryPressureObserver();
+    WidgetsBinding.instance.addObserver(observer);
+    final ByteData message = const JSONMessageCodec()
+        .encodeMessage(<String, dynamic>{'type': 'memoryPressure'});
+    await BinaryMessages.handlePlatformMessage(
+        'flutter/system', message, (_) {});
+    expect(observer.sawMemoryPressure, true);
+    WidgetsBinding.instance.removeObserver(observer);
+  });
+
+  testWidgets('handleLifecycleStateChanged callback',
+      (WidgetTester tester) async {
+    final AppLifecycleStateObserver observer = AppLifecycleStateObserver();
+    WidgetsBinding.instance.addObserver(observer);
+
+    ByteData message =
+        const StringCodec().encodeMessage('AppLifecycleState.paused');
+    await BinaryMessages.handlePlatformMessage(
+        'flutter/lifecycle', message, (_) {});
+    expect(observer.lifecycleState, AppLifecycleState.paused);
+
+    message = const StringCodec().encodeMessage('AppLifecycleState.resumed');
+    await BinaryMessages.handlePlatformMessage(
+        'flutter/lifecycle', message, (_) {});
+    expect(observer.lifecycleState, AppLifecycleState.resumed);
+
+    message = const StringCodec().encodeMessage('AppLifecycleState.inactive');
+    await BinaryMessages.handlePlatformMessage(
+        'flutter/lifecycle', message, (_) {});
+    expect(observer.lifecycleState, AppLifecycleState.inactive);
+
+    message = const StringCodec().encodeMessage('AppLifecycleState.suspending');
+    await BinaryMessages.handlePlatformMessage(
+        'flutter/lifecycle', message, (_) {});
+    expect(observer.lifecycleState, AppLifecycleState.suspending);
+  });
+
+  testWidgets('didPushRoute callback', (WidgetTester tester) async {
+    final PushRouteObserver observer = PushRouteObserver();
+    WidgetsBinding.instance.addObserver(observer);
+
+    const String testRouteName = 'testRouteName';
+    final ByteData message = const JSONMethodCodec()
+        .encodeMethodCall(const MethodCall('pushRoute', testRouteName));
+    await BinaryMessages.handlePlatformMessage(
+        'flutter/navigation', message, (_) {});
+    expect(observer.pushedRoute, testRouteName);
+
+    WidgetsBinding.instance.removeObserver(observer);
+  });
+
+  testWidgets('Application lifecycle affects frame scheduling',
+      (WidgetTester tester) async {
+    ByteData message;
+    expect(tester.binding.hasScheduledFrame, isFalse);
+
+    message = const StringCodec().encodeMessage('AppLifecycleState.paused');
+    await BinaryMessages.handlePlatformMessage(
+        'flutter/lifecycle', message, (_) {});
+    expect(tester.binding.hasScheduledFrame, isFalse);
+
+    message = const StringCodec().encodeMessage('AppLifecycleState.resumed');
+    await BinaryMessages.handlePlatformMessage(
+        'flutter/lifecycle', message, (_) {});
+    expect(tester.binding.hasScheduledFrame, isTrue);
+    await tester.pump();
+    expect(tester.binding.hasScheduledFrame, isFalse);
+
+    message = const StringCodec().encodeMessage('AppLifecycleState.inactive');
+    await BinaryMessages.handlePlatformMessage(
+        'flutter/lifecycle', message, (_) {});
+    expect(tester.binding.hasScheduledFrame, isFalse);
+
+    message = const StringCodec().encodeMessage('AppLifecycleState.suspending');
+    await BinaryMessages.handlePlatformMessage(
+        'flutter/lifecycle', message, (_) {});
+    expect(tester.binding.hasScheduledFrame, isFalse);
+
+    message = const StringCodec().encodeMessage('AppLifecycleState.inactive');
+    await BinaryMessages.handlePlatformMessage(
+        'flutter/lifecycle', message, (_) {});
+    expect(tester.binding.hasScheduledFrame, isTrue);
+    await tester.pump();
+    expect(tester.binding.hasScheduledFrame, isFalse);
+
+    message = const StringCodec().encodeMessage('AppLifecycleState.paused');
+    await BinaryMessages.handlePlatformMessage(
+        'flutter/lifecycle', message, (_) {});
+    expect(tester.binding.hasScheduledFrame, isFalse);
+
+    tester.binding.scheduleFrame();
+    expect(tester.binding.hasScheduledFrame, isFalse);
+
+    tester.binding.scheduleForcedFrame();
+    expect(tester.binding.hasScheduledFrame, isTrue);
+    await tester.pump();
+    expect(tester.binding.hasScheduledFrame, isFalse);
+
+    int frameCount = 0;
+    tester.binding.addPostFrameCallback((Duration duration) {
+      frameCount += 1;
+    });
+    expect(tester.binding.hasScheduledFrame, isFalse);
+    await tester.pump(const Duration(milliseconds: 1));
+    expect(tester.binding.hasScheduledFrame, isFalse);
+    expect(frameCount, 0);
+
+    tester.binding
+        .scheduleWarmUpFrame(); // this actually tests flutter_test's implementation
+    expect(tester.binding.hasScheduledFrame, isFalse);
+    expect(frameCount, 1);
+  });
+}