Revert "Migrate to ChannelBuffers.push (#76288)" (#81226)

This reverts commit c26ed03c8a77810136cc087ae60048ace062842d.

dev/automated_tests/flutter_test/ticker_test.dart

@@ -11,6 +11,6 @@ void main() {
     Ticker((Duration duration) { }).start();
 
     final ByteData? message = const StringCodec().encodeMessage('AppLifecycleState.paused');
-    await tester.binding.defaultBinaryMessenger.handlePlatformMessage('flutter/lifecycle', message, (_) {});
+    await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage('flutter/lifecycle', message, (_) {});
   });
 }

examples/hello_world/test_driver/smoke_web_engine_test.dart

@@ -5,7 +5,7 @@
 import 'dart:async';
 
 import 'package:flutter_driver/flutter_driver.dart';
-import 'package:test/test.dart';
+import 'package:test/test.dart' hide TypeMatcher, isInstanceOf;
 import 'package:webdriver/async_io.dart';
 
 /// The following test is used as a simple smoke test for verifying Flutter
@@ -33,7 +33,6 @@ void main() {
     test('enable accessibility', () async {
       await driver.enableAccessibility();
 
-      // TODO(ianh): this delay violates our style guide. We should instead wait for a triggering event.
       await Future<void>.delayed(const Duration(seconds: 2));
 
       // Elements with tag "flt-semantics" would show up after enabling

packages/flutter/lib/src/foundation/binding.dart

@@ -104,8 +104,8 @@ abstract class BindingBase {
   /// A number of additional bindings are defined as extensions of
   /// [BindingBase], e.g., [ServicesBinding], [RendererBinding], and
   /// [WidgetsBinding]. Each of these bindings define behaviors that interact
-  /// with a [ui.PlatformDispatcher], e.g., [ServicesBinding] registers
+  /// with a [ui.PlatformDispatcher], e.g., [ServicesBinding] registers a
-  /// listeners with the [ChannelBuffers], and [RendererBinding]
+  /// [ui.PlatformDispatcher.onPlatformMessage] handler, and [RendererBinding]
   /// registers [ui.PlatformDispatcher.onMetricsChanged],
   /// [ui.PlatformDispatcher.onTextScaleFactorChanged],
   /// [ui.PlatformDispatcher.onSemanticsEnabledChanged], and

packages/flutter/lib/src/services/binary_messenger.dart

@@ -2,9 +2,12 @@
 // 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 'dart:ui' as ui;
 
+import 'binding.dart';
+
 /// A function which takes a platform message and asynchronously returns an encoded response.
 typedef MessageHandler = Future<ByteData?>? Function(ByteData? message);
 
@@ -16,39 +19,12 @@ abstract class BinaryMessenger {
   /// const constructors so that they can be used in const expressions.
   const BinaryMessenger();
 
-  /// Queues a message.
+  /// Calls the handler registered for the given channel.
   ///
-  /// The returned future completes immediately.
+  /// Typically called by [ServicesBinding] to handle platform messages received
-  ///
+  /// from [dart:ui.PlatformDispatcher.onPlatformMessage].
-  /// This method adds the provided message to the given channel (named by the
-  /// `channel` argument) of the [ChannelBuffers] object. This simulates what
-  /// happens when a plugin on the platform thread (e.g. Kotlin or Swift code)
-  /// sends a message to the plugin package on the Dart thread.
-  ///
-  /// The `data` argument contains the message as encoded bytes. (The format
-  /// used for the message depends on the channel.)
-  ///
-  /// The `callback` argument, if non-null, is eventually invoked with the
-  /// response that would have been sent to the platform thread.
-  ///
-  /// In production code, it is more efficient to call
-  /// `ServicesBinding.instance.channelBuffers.push` directly.
-  ///
-  /// In tests, consider using
-  /// `tester.binding.defaultBinaryMessenger.handlePlatformMessage` (see
-  /// [WidgetTester], [TestWidgetsFlutterBinding], [TestDefaultBinaryMessenger],
-  /// and [TestDefaultBinaryMessenger.handlePlatformMessage] respectively).
   ///
   /// To register a handler for a given message channel, see [setMessageHandler].
-  ///
-  /// To send a message _to_ a plugin on the platform thread, see [send].
-  // TODO(ianh): deprecate this method once cocoon and other customer_tests are migrated:
-  // @NotYetDeprecated(
-  //   'Instead of calling this method, use ServicesBinding.instance.channelBuffers.push. '
-  //   'In tests, consider using tester.binding.defaultBinaryMessenger.handlePlatformMessage '
-  //   'or TestDefaultBinaryMessenger.instance.defaultBinaryMessenger.handlePlatformMessage. '
-  //   'This feature was deprecated after v2.1.0-10.0.pre.'
-  // )
   Future<void> handlePlatformMessage(String channel, ByteData? data, ui.PlatformMessageResponseCallback? callback);
 
   /// Send a binary message to the platform plugins on the given channel.
@@ -67,6 +43,37 @@ abstract class BinaryMessenger {
   /// The handler's return value, if non-null, is sent as a response, unencoded.
   void setMessageHandler(String channel, MessageHandler? handler);
 
-  // Looking for setMockMessageHandler or checkMockMessageHandler?
+  /// Returns true if the `handler` argument matches the `handler` previously
-  // See this shim package: packages/flutter_test/lib/src/deprecated.dart
+  /// passed to [setMessageHandler].
+  ///
+  /// This method is useful for tests or test harnesses that want to assert the
+  /// handler for the specified channel has not been altered by a previous test.
+  ///
+  /// Passing null for the `handler` returns true if the handler for the
+  /// `channel` is not set.
+  bool checkMessageHandler(String channel, MessageHandler? handler);
+
+  /// Set a mock callback for intercepting messages from the [send] method on
+  /// this class, on the given channel, without decoding them.
+  ///
+  /// The given callback will replace the currently registered mock callback for
+  /// that channel, if any. To remove the mock handler, pass null as the
+  /// `handler` argument.
+  ///
+  /// The handler's return value, if non-null, is used as a response, unencoded.
+  ///
+  /// This is intended for testing. Messages intercepted in this manner are not
+  /// sent to platform plugins.
+  void setMockMessageHandler(String channel, MessageHandler? handler);
+
+  /// Returns true if the `handler` argument matches the `handler` previously
+  /// passed to [setMockMessageHandler].
+  ///
+  /// This method is useful for tests or test harnesses that want to assert the
+  /// mock handler for the specified channel has not been altered by a previous
+  /// test.
+  ///
+  /// Passing null for the `handler` returns true if the handler for the
+  /// `channel` is not set.
+  bool checkMockMessageHandler(String channel, MessageHandler? handler);
 }

packages/flutter/lib/src/services/binding.dart

@@ -28,6 +28,7 @@ mixin ServicesBinding on BindingBase, SchedulerBinding {
     _instance = this;
     _defaultBinaryMessenger = createBinaryMessenger();
     _restorationManager = createRestorationManager();
+    window.onPlatformMessage = defaultBinaryMessenger.handlePlatformMessage;
     initLicenses();
     SystemChannels.system.setMessageHandler((dynamic message) => handleSystemMessage(message as Object));
     SystemChannels.lifecycle.setMessageHandler(_handleLifecycleMessage);
@@ -46,28 +47,6 @@ mixin ServicesBinding on BindingBase, SchedulerBinding {
   BinaryMessenger get defaultBinaryMessenger => _defaultBinaryMessenger;
   late BinaryMessenger _defaultBinaryMessenger;
 
-  /// The low level buffering and dispatch mechanism for messages sent by
-  /// plugins on the engine side to their corresponding plugin code on
-  /// the framework side.
-  ///
-  /// This exposes the [dart:ui.channelBuffers] object. Bindings can override
-  /// this getter to intercept calls to the [ChannelBuffers] mechanism (for
-  /// example, for tests).
-  ///
-  /// In production, direct access to this object should not be necessary.
-  /// Messages are received and dispatched by the [defaultBinaryMessenger]. This
-  /// object is primarily used to send mock messages in tests, via the
-  /// [ChannelBuffers.push] method (simulating a plugin sending a message to the
-  /// framework).
-  ///
-  /// See also:
-  ///
-  ///  * [PlatformDispatcher.sendPlatformMessage], which is used for sending
-  ///    messages to plugins from the framework (the opposite of
-  ///    [channelBuffers]).
-  ///  * [platformDispatcher], the [PlatformDispatcher] singleton.
-  ui.ChannelBuffers get channelBuffers => ui.channelBuffers;
-
   /// Creates a default [BinaryMessenger] instance that can be used for sending
   /// platform messages.
   @protected
@@ -75,6 +54,7 @@ mixin ServicesBinding on BindingBase, SchedulerBinding {
     return const _DefaultBinaryMessenger._();
   }
 
+
   /// Called when the operating system notifies the application of a memory
   /// pressure situation.
   ///
@@ -257,20 +237,17 @@ mixin ServicesBinding on BindingBase, SchedulerBinding {
 class _DefaultBinaryMessenger extends BinaryMessenger {
   const _DefaultBinaryMessenger._();
 
-  @override
+  // Handlers for incoming messages from platform plugins.
-  Future<void> handlePlatformMessage(
+  // This is static so that this class can have a const constructor.
-    String channel,
+  static final Map<String, MessageHandler> _handlers =
-    ByteData? message,
+      <String, MessageHandler>{};
-    ui.PlatformMessageResponseCallback? callback,
-  ) async {
-    ui.channelBuffers.push(channel, message, (ByteData? data) {
-      if (callback != null)
-        callback(data);
-    });
-  }
 
-  @override
+  // Mock handlers that intercept and respond to outgoing messages.
-  Future<ByteData?> send(String channel, ByteData? message) {
+  // This is static so that this class can have a const constructor.
+  static final Map<String, MessageHandler> _mockHandlers =
+      <String, MessageHandler>{};
+
+  Future<ByteData?> _sendPlatformMessage(String channel, ByteData? message) {
     final Completer<ByteData?> completer = Completer<ByteData?>();
     // ui.PlatformDispatcher.instance is accessed directly instead of using
     // ServicesBinding.instance.platformDispatcher because this method might be
@@ -279,8 +256,6 @@ class _DefaultBinaryMessenger extends BinaryMessenger {
     // ui.PlatformDispatcher.instance because the PlatformDispatcher may be
     // dependency injected elsewhere with a different instance. However, static
     // access at this location seems to be the least bad option.
-    // TODO(ianh): Use ServicesBinding.instance once we have better diagnostics
-    // on that getter.
     ui.PlatformDispatcher.instance.sendPlatformMessage(channel, message, (ByteData? reply) {
       try {
         completer.complete(reply);
@@ -296,27 +271,70 @@ class _DefaultBinaryMessenger extends BinaryMessenger {
     return completer.future;
   }
 
+  @override
+  // TODO(goderbauer): Add pragma (and enable test in
+  //   break_on_framework_exceptions_test.dart) when it works on async methods,
+  //   https://github.com/dart-lang/sdk/issues/45673
+  // @pragma('vm:notify-debugger-on-exception')
+  Future<void> handlePlatformMessage(
+    String channel,
+    ByteData? data,
+    ui.PlatformMessageResponseCallback? callback,
+  ) async {
+    ByteData? response;
+    try {
+      final MessageHandler? handler = _handlers[channel];
+      if (handler != null) {
+        response = await handler(data);
+      } else {
+        ui.channelBuffers.push(channel, data, callback!);
+        callback = null;
+      }
+    } catch (exception, stack) {
+      FlutterError.reportError(FlutterErrorDetails(
+        exception: exception,
+        stack: stack,
+        library: 'services library',
+        context: ErrorDescription('during a platform message callback'),
+      ));
+    } finally {
+      if (callback != null) {
+        callback(response);
+      }
+    }
+  }
+
+  @override
+  Future<ByteData?>? send(String channel, ByteData? message) {
+    final MessageHandler? handler = _mockHandlers[channel];
+    if (handler != null)
+      return handler(message);
+    return _sendPlatformMessage(channel, message);
+  }
+
   @override
   void setMessageHandler(String channel, MessageHandler? handler) {
     if (handler == null) {
-      ui.channelBuffers.clearListener(channel);
+      _handlers.remove(channel);
     } else {
-      ui.channelBuffers.setListener(channel, (ByteData? data, ui.PlatformMessageResponseCallback callback) async {
+      _handlers[channel] = handler;
-        ByteData? response;
+      ui.channelBuffers.drain(channel, (ByteData? data, ui.PlatformMessageResponseCallback callback) async {
-        try {
+        await handlePlatformMessage(channel, data, callback);
-          response = await handler(data);
-        } catch (exception, stack) {
-
-          FlutterError.reportError(FlutterErrorDetails(
-            exception: exception,
-            stack: stack,
-            library: 'services library',
-            context: ErrorDescription('during a platform message callback'),
-          ));
-        } finally {
-          callback(response);
-        }
       });
     }
   }
+
+  @override
+  bool checkMessageHandler(String channel, MessageHandler? handler) => _handlers[channel] == handler;
+
+  @override
+  void setMockMessageHandler(String channel, MessageHandler? handler) {
+    if (handler == null)
+      _mockHandlers.remove(channel);
+    else
+      _mockHandlers[channel] = handler;
+  }
+
+  @override
+  bool checkMockMessageHandler(String channel, MessageHandler? handler) => _mockHandlers[channel] == handler;
 }

packages/flutter/lib/src/services/message_codec.dart

@@ -95,6 +95,7 @@ abstract class MethodCodec {
   ByteData encodeErrorEnvelope({ required String code, String? message, Object? details});
 }
 
+
 /// Thrown to indicate that a platform interaction failed in the platform
 /// plugin.
 ///

packages/flutter/lib/src/services/platform_channel.dart

@@ -75,10 +75,31 @@ class BasicMessageChannel<T> {
     }
   }
 
-  // Looking for setMockMessageHandler?
+  /// Sets a mock callback for intercepting messages sent on this channel.
-  // See this shim package: packages/flutter_test/lib/src/deprecated.dart
+  /// Messages may be null.
+  ///
+  /// The given callback will replace the currently registered mock callback for
+  /// this channel, if any. To remove the mock handler, pass null as the
+  /// `handler` argument.
+  ///
+  /// The handler's return value is used as a message reply. It may be null.
+  ///
+  /// This is intended for testing. Messages intercepted in this manner are not
+  /// sent to platform plugins.
+  void setMockMessageHandler(Future<T> Function(T? message)? handler) {
+    if (handler == null) {
+      binaryMessenger.setMockMessageHandler(name, null);
+    } else {
+      binaryMessenger.setMockMessageHandler(name, (ByteData? message) async {
+        return codec.encodeMessage(await handler(codec.decodeMessage(message)));
+      });
+    }
+  }
 }
 
+Expando<Object> _methodChannelHandlers = Expando<Object>();
+Expando<Object> _methodChannelMockHandlers = Expando<Object>();
+
 /// A named channel for communicating with platform plugins using asynchronous
 /// method calls.
 ///
@@ -353,6 +374,7 @@ class MethodChannel {
   /// similarly to what happens if no method call handler has been set.
   /// Any other exception results in an error envelope being sent.
   void setMethodCallHandler(Future<dynamic> Function(MethodCall call)? handler) {
+    _methodChannelHandlers[this] = handler;
     binaryMessenger.setMessageHandler(
       name,
       handler == null
@@ -361,7 +383,53 @@ class MethodChannel {
     );
   }
 
-  Future<ByteData?> _handleAsMethodCall(ByteData? message, Future<dynamic> Function(MethodCall call) handler) async {
+  /// Returns true if the `handler` argument matches the `handler` previously
+  /// passed to [setMethodCallHandler].
+  ///
+  /// This method is useful for tests or test harnesses that want to assert the
+  /// handler for the specified channel has not been altered by a previous test.
+  ///
+  /// Passing null for the `handler` returns true if the handler for the channel
+  /// is not set.
+  bool checkMethodCallHandler(Future<dynamic> Function(MethodCall call)? handler) => _methodChannelHandlers[this] == handler;
+
+  /// Sets a mock callback for intercepting method invocations on this channel.
+  ///
+  /// The given callback will replace the currently registered mock callback for
+  /// this channel, if any. To remove the mock handler, pass null as the
+  /// `handler` argument.
+  ///
+  /// Later calls to [invokeMethod] will result in a successful result,
+  /// a [PlatformException] or a [MissingPluginException], determined by how
+  /// the future returned by the mock callback completes. The [codec] of this
+  /// channel is used to encode and decode values and errors.
+  ///
+  /// This is intended for testing. Method calls intercepted in this manner are
+  /// not sent to platform plugins.
+  ///
+  /// The provided `handler` must return a `Future` that completes with the
+  /// return value of the call. The value will be encoded using
+  /// [MethodCodec.encodeSuccessEnvelope], to act as if platform plugin had
+  /// returned that value.
+  void setMockMethodCallHandler(Future<dynamic>? Function(MethodCall call)? handler) {
+    _methodChannelMockHandlers[this] = handler;
+    binaryMessenger.setMockMessageHandler(
+      name,
+      handler == null ? null : (ByteData? message) => _handleAsMethodCall(message, handler),
+    );
+  }
+
+  /// Returns true if the `handler` argument matches the `handler` previously
+  /// passed to [setMockMethodCallHandler].
+  ///
+  /// This method is useful for tests or test harnesses that want to assert the
+  /// handler for the specified channel has not been altered by a previous test.
+  ///
+  /// Passing null for the `handler` returns true if the handler for the channel
+  /// is not set.
+  bool checkMockMethodCallHandler(Future<dynamic> Function(MethodCall call)? handler) => _methodChannelMockHandlers[this] == handler;
+
+  Future<ByteData?> _handleAsMethodCall(ByteData? message, Future<dynamic>? Function(MethodCall call) handler) async {
     final MethodCall call = codec.decodeMethodCall(message);
     try {
       return codec.encodeSuccessEnvelope(await handler(call));
@@ -377,9 +445,6 @@ class MethodChannel {
       return codec.encodeErrorEnvelope(code: 'error', message: e.toString(), details: null);
     }
   }
-
-  // Looking for setMockMethodCallHandler or checkMethodCallHandler?
-  // See this shim package: packages/flutter_test/lib/src/deprecated.dart
 }
 
 /// A [MethodChannel] that ignores missing platform plugins.
@@ -407,6 +472,7 @@ class OptionalMethodChannel extends MethodChannel {
     final Map<dynamic, dynamic>? result = await invokeMethod<Map<dynamic, dynamic>>(method, arguments);
     return result?.cast<K, V>();
   }
+
 }
 
 /// A named channel for communicating with platform plugins using event streams.

packages/flutter/lib/src/services/restoration.dart

@@ -166,6 +166,7 @@ class RestorationManager extends ChangeNotifier {
   /// that communications channel, or to set it up differently, as necessary.
   @protected
   void initChannels() {
+    assert(!SystemChannels.restoration.checkMethodCallHandler(_methodHandler));
     SystemChannels.restoration.setMethodCallHandler(_methodHandler);
   }
 

packages/flutter/lib/src/services/text_input.dart

@@ -1517,7 +1517,7 @@ class TextInput {
     assert(shouldSave != null);
     TextInput._instance._channel.invokeMethod<void>(
       'TextInput.finishAutofillContext',
-      shouldSave,
+      shouldSave ,
     );
   }
 }

packages/flutter/lib/src/widgets/editable_text.dart

@@ -2360,13 +2360,11 @@ class EditableTextState extends State<EditableText> with AutomaticKeepAliveClien
 
   void _cursorWaitForStart(Timer timer) {
     assert(_kCursorBlinkHalfPeriod > _fadeDuration);
-    assert(!EditableText.debugDeterministicCursor);
     _cursorTimer?.cancel();
     _cursorTimer = Timer.periodic(_kCursorBlinkHalfPeriod, _cursorTick);
   }
 
   void _startCursorTimer() {
-    assert(_cursorTimer == null);
     _targetCursorVisibility = true;
     _cursorBlinkOpacityController.value = 1.0;
     if (EditableText.debugDeterministicCursor)

packages/flutter/test/cupertino/picker_test.dart

@@ -202,7 +202,7 @@ void main() {
         final List<int> selectedItems = <int>[];
         final List<MethodCall> systemCalls = <MethodCall>[];
 
-        tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+        SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
           systemCalls.add(methodCall);
         });
 
@@ -253,7 +253,7 @@ void main() {
         final List<int> selectedItems = <int>[];
         final List<MethodCall> systemCalls = <MethodCall>[];
 
-        tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+        SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
           systemCalls.add(methodCall);
         });
 

packages/flutter/test/cupertino/refresh_test.dart

@@ -173,7 +173,7 @@ void main() {
     testWidgets('drag past threshold triggers refresh task', (WidgetTester tester) async {
       final List<MethodCall> platformCallLog = <MethodCall>[];
 
-      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+      SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
         platformCallLog.add(methodCall);
       });
 

packages/flutter/test/cupertino/scrollbar_test.dart

@@ -132,9 +132,9 @@ void main() {
     await tester.pump();
 
     int hapticFeedbackCalls = 0;
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       if (methodCall.method == 'HapticFeedback.vibrate') {
-        hapticFeedbackCalls += 1;
+        hapticFeedbackCalls++;
       }
     });
 
@@ -680,9 +680,9 @@ void main() {
     await tester.pump();
 
     int hapticFeedbackCalls = 0;
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       if (methodCall.method == 'HapticFeedback.vibrate') {
-        hapticFeedbackCalls += 1;
+        hapticFeedbackCalls++;
       }
     });
 

packages/flutter/test/cupertino/switch_test.dart

@@ -47,7 +47,7 @@ void main() {
 
     final List<MethodCall> log = <MethodCall>[];
 
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -87,7 +87,7 @@ void main() {
     bool value2 = false;
     final List<MethodCall> log = <MethodCall>[];
 
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -154,7 +154,7 @@ void main() {
     bool value = false;
     final List<MethodCall> log = <MethodCall>[];
 
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -192,7 +192,7 @@ void main() {
     bool value = false;
 
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 

packages/flutter/test/cupertino/text_field_test.dart

@@ -163,7 +163,7 @@ class PathPointsMatcher extends Matcher {
 void main() {
   TestWidgetsFlutterBinding.ensureInitialized();
   final MockClipboard mockClipboard = MockClipboard();
-  TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, mockClipboard.handleMethodCall);
+  SystemChannels.platform.setMockMethodCallHandler(mockClipboard.handleMethodCall);
 
   // Returns the first RenderEditable.
   RenderEditable findRenderEditable(WidgetTester tester) {
@@ -3227,7 +3227,7 @@ void main() {
 
   testWidgets('text field respects keyboardAppearance from theme', (WidgetTester tester) async {
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall methodCall) async {
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -3250,7 +3250,7 @@ void main() {
 
   testWidgets('text field can override keyboardAppearance from theme', (WidgetTester tester) async {
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall methodCall) async {
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 

packages/flutter/test/cupertino/text_selection_test.dart

@@ -66,7 +66,7 @@ const _LongCupertinoLocalizations longLocalizations = _LongCupertinoLocalization
 void main() {
   TestWidgetsFlutterBinding.ensureInitialized();
   final MockClipboard mockClipboard = MockClipboard();
-  TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, mockClipboard.handleMethodCall);
+  SystemChannels.platform.setMockMethodCallHandler(mockClipboard.handleMethodCall);
 
   // Returns true iff the button is visually enabled.
   bool appearsEnabled(WidgetTester tester, String text) {

packages/flutter/test/foundation/service_extensions_test.dart

@@ -21,8 +21,7 @@ class TestServiceExtensionsBinding extends BindingBase
        PaintingBinding,
        SemanticsBinding,
        RendererBinding,
-       WidgetsBinding,
+       WidgetsBinding {
-       TestDefaultBinaryMessengerBinding {
 
   final Map<String, ServiceExtensionCallback> extensions = <String, ServiceExtensionCallback>{};
 
@@ -468,7 +467,7 @@ void main() {
     bool completed;
 
     completed = false;
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler('flutter/assets', (ByteData? message) async {
+    ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler('flutter/assets', (ByteData? message) async {
       expect(utf8.decode(message!.buffer.asUint8List()), 'test');
       completed = true;
       return ByteData(5); // 0x0000000000
@@ -495,7 +494,7 @@ void main() {
     });
     expect(data, isFalse);
     expect(completed, isTrue);
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler('flutter/assets', null);
+    ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler('flutter/assets', null);
   });
 
   test('Service extensions - exit', () async {

packages/flutter/test/gestures/gesture_binding_resample_event_on_widget_test.dart

@@ -2,6 +2,12 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+// Logically this file should be part of `gesture_binding_test.dart` but is here
+// due to conflict of `flutter_test` and `package:test`.
+// See https://github.com/dart-lang/matcher/issues/98
+// TODO(CareF): Consider combine this file back to `gesture_binding_test.dart`
+// after #98 is fixed.
+
 import 'dart:ui' as ui;
 
 import 'package:clock/clock.dart';

packages/flutter/test/material/checkbox_test.dart

@@ -267,7 +267,7 @@ void main() {
   testWidgets('has semantic events', (WidgetTester tester) async {
     dynamic semanticEvent;
     bool? checkboxValue = false;
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, (dynamic message) async {
+    SystemChannels.accessibility.setMockMessageHandler((dynamic message) async {
       semanticEvent = message;
     });
     final SemanticsTester semanticsTester = SemanticsTester(tester);
@@ -300,7 +300,7 @@ void main() {
     });
     expect(object.debugSemantics!.getSemanticsData().hasAction(SemanticsAction.tap), true);
 
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, null);
+    SystemChannels.accessibility.setMockMessageHandler(null);
     semanticsTester.dispose();
   });
 

packages/flutter/test/material/feedback_test.dart

@@ -27,14 +27,14 @@ void main () {
 
     setUp(() {
       semanticEvents = <Map<String, Object>>[];
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, (dynamic message) async {
+      SystemChannels.accessibility.setMockMessageHandler((dynamic message) async {
         final Map<dynamic, dynamic> typedMessage = message as Map<dynamic, dynamic>;
         semanticEvents.add(typedMessage.cast<String, Object>());
       });
     });
 
     tearDown(() {
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, null);
+      SystemChannels.accessibility.setMockMessageHandler(null);
     });
 
     testWidgets('forTap', (WidgetTester tester) async {

packages/flutter/test/material/feedback_tester.dart

@@ -3,7 +3,6 @@
 // found in the LICENSE file.
 
 import 'package:flutter/services.dart';
-import 'package:flutter_test/flutter_test.dart';
 
 /// Tracks how often feedback has been requested since its instantiation.
 ///
@@ -11,7 +10,13 @@ import 'package:flutter_test/flutter_test.dart';
 /// cannot be used in combination with other classes that do the same.
 class FeedbackTester {
   FeedbackTester() {
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, _handler);
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
+      if (methodCall.method == 'HapticFeedback.vibrate')
+        _hapticCount++;
+      if (methodCall.method == 'SystemSound.play' &&
+          methodCall.arguments == SystemSoundType.click.toString())
+        _clickSoundCount++;
+    });
   }
 
   /// Number of times haptic feedback was requested (vibration).
@@ -22,17 +27,8 @@ class FeedbackTester {
   int get clickSoundCount => _clickSoundCount;
   int _clickSoundCount = 0;
 
-  Future<void> _handler(MethodCall methodCall) async {
-    if (methodCall.method == 'HapticFeedback.vibrate')
-      _hapticCount++;
-    if (methodCall.method == 'SystemSound.play' &&
-        methodCall.arguments == SystemSoundType.click.toString())
-      _clickSoundCount++;
-  }
-
   /// Stops tracking.
   void dispose() {
-    assert(TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.checkMockMessageHandler(SystemChannels.platform.name, _handler));
+    SystemChannels.platform.setMockMethodCallHandler(null);
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, null);
   }
 }

packages/flutter/test/material/input_date_picker_form_field_test.dart

@@ -241,9 +241,9 @@ void main() {
 
       // Fill the clipboard so that the Paste option is available in the text
       // selection menu.
-      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, mockClipboard.handleMethodCall);
+      SystemChannels.platform.setMockMethodCallHandler(mockClipboard.handleMethodCall);
       await Clipboard.setData(const ClipboardData(text: 'Clipboard data'));
-      addTearDown(() => tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, null));
+      addTearDown(() => SystemChannels.platform.setMockMethodCallHandler(null));
 
       await tester.pumpWidget(_inputDatePickerField(autofocus: true));
       await tester.pumpAndSettle();

packages/flutter/test/material/radio_list_tile_test.dart

@@ -539,7 +539,7 @@ void main() {
     final Key key = UniqueKey();
     dynamic semanticEvent;
     int? radioValue = 2;
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, (dynamic message) async {
+    SystemChannels.accessibility.setMockMessageHandler((dynamic message) async {
       semanticEvent = message;
     });
 
@@ -570,7 +570,7 @@ void main() {
     expect(object.debugSemantics!.getSemanticsData().hasAction(SemanticsAction.tap), true);
 
     semantics.dispose();
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, null);
+    SystemChannels.accessibility.setMockMessageHandler(null);
   });
 
   testWidgets('RadioListTile can autofocus unless disabled.', (WidgetTester tester) async {

packages/flutter/test/material/radio_test.dart

@@ -292,7 +292,7 @@ void main() {
     final Key key = UniqueKey();
     dynamic semanticEvent;
     int? radioValue = 2;
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, (dynamic message) async {
+    SystemChannels.accessibility.setMockMessageHandler((dynamic message) async {
       semanticEvent = message;
     });
 
@@ -319,7 +319,7 @@ void main() {
     expect(object.debugSemantics!.getSemanticsData().hasAction(SemanticsAction.tap), true);
 
     semantics.dispose();
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, null);
+    SystemChannels.accessibility.setMockMessageHandler(null);
   });
 
   testWidgets('Radio ink ripple is displayed correctly', (WidgetTester tester) async {

packages/flutter/test/material/search_test.dart

@@ -32,12 +32,12 @@ void main() {
   setUp(() async {
     // Fill the clipboard so that the Paste option is available in the text
     // selection menu.
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, mockClipboard.handleMethodCall);
+    SystemChannels.platform.setMockMethodCallHandler(mockClipboard.handleMethodCall);
     await Clipboard.setData(const ClipboardData(text: 'Clipboard data'));
   });
 
   tearDown(() {
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, null);
+    SystemChannels.platform.setMockMethodCallHandler(null);
   });
 
   testWidgets('Can open and close search', (WidgetTester tester) async {

packages/flutter/test/material/switch_test.dart

@@ -571,7 +571,7 @@ void main() {
   testWidgets('switch has semantic events', (WidgetTester tester) async {
     dynamic semanticEvent;
     bool value = false;
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, (dynamic message) async {
+    SystemChannels.accessibility.setMockMessageHandler((dynamic message) async {
       semanticEvent = message;
     });
     final SemanticsTester semanticsTester = SemanticsTester(tester);
@@ -609,13 +609,13 @@ void main() {
     expect(object.debugSemantics!.getSemanticsData().hasAction(SemanticsAction.tap), true);
 
     semanticsTester.dispose();
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, null);
+    SystemChannels.accessibility.setMockMessageHandler(null);
   });
 
   testWidgets('switch sends semantic events from parent if fully merged', (WidgetTester tester) async {
     dynamic semanticEvent;
     bool value = false;
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, (dynamic message) async {
+    SystemChannels.accessibility.setMockMessageHandler((dynamic message) async {
       semanticEvent = message;
     });
     final SemanticsTester semanticsTester = SemanticsTester(tester);
@@ -659,7 +659,7 @@ void main() {
     expect(object.debugSemantics!.getSemanticsData().hasAction(SemanticsAction.tap), true);
 
     semanticsTester.dispose();
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, null);
+    SystemChannels.accessibility.setMockMessageHandler(null);
   });
 
   testWidgets('Switch.adaptive', (WidgetTester tester) async {

packages/flutter/test/material/text_field_test.dart

@@ -2,7 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'dart:async';
 import 'dart:math' as math;
 import 'dart:ui' as ui show window, BoxHeightStyle, BoxWidthStyle;
 
@@ -165,20 +164,14 @@ void main() {
 
   setUp(() async {
     debugResetSemanticsIdCounter();
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(
+    SystemChannels.platform.setMockMethodCallHandler(mockClipboard.handleMethodCall);
-      SystemChannels.platform,
-      mockClipboard.handleMethodCall,
-    );
     // Fill the clipboard so that the Paste option is available in the text
     // selection menu.
     await Clipboard.setData(const ClipboardData(text: 'Clipboard data'));
   });
 
   tearDown(() {
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(
+    SystemChannels.platform.setMockMethodCallHandler(null);
-      SystemChannels.platform,
-      null,
-    );
   });
 
   final Key textFieldKey = UniqueKey();
@@ -344,7 +337,7 @@ void main() {
 
   testWidgets('TextField has consistent size', (WidgetTester tester) async {
     final Key textFieldKey = UniqueKey();
-    String? textFieldValue;
+    late String textFieldValue;
 
     await tester.pumpWidget(
       overlay(
@@ -367,16 +360,15 @@ void main() {
 
     Future<void> checkText(String testValue) async {
       return TestAsyncUtils.guard(() async {
-        expect(textFieldValue, isNull);
         await tester.enterText(find.byType(TextField), testValue);
         // Check that the onChanged event handler fired.
         expect(textFieldValue, equals(testValue));
-        textFieldValue = null;
         await skipPastScrollingAnimation(tester);
       });
     }
 
     await checkText(' ');
+
     expect(findTextFieldBox(), equals(inputBox));
     expect(inputBox.size, equals(emptyInputSize));
 
@@ -422,8 +414,6 @@ void main() {
       text: 'X',
       selection: TextSelection.collapsed(offset: 1),
     ));
-    await tester.idle();
-    expect(tester.state(find.byType(EditableText)), editableText);
     await checkCursorToggle();
   });
 
@@ -4697,8 +4687,8 @@ void main() {
       );
 
     String clipboardContent = '';
-    tester.binding.defaultBinaryMessenger
+    SystemChannels.platform
-      .setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+      .setMockMethodCallHandler((MethodCall methodCall) async {
         if (methodCall.method == 'Clipboard.setData')
           clipboardContent = methodCall.arguments['text'] as String;
         else if (methodCall.method == 'Clipboard.getData')
@@ -4770,8 +4760,8 @@ void main() {
       );
 
     String clipboardContent = '';
-    tester.binding.defaultBinaryMessenger
+    SystemChannels.platform
-      .setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+      .setMockMethodCallHandler((MethodCall methodCall) async {
         if (methodCall.method == 'Clipboard.setData')
           clipboardContent = methodCall.arguments['text'] as String;
         else if (methodCall.method == 'Clipboard.getData')
@@ -4843,8 +4833,8 @@ void main() {
     );
 
     const String clipboardContent = 'I love Flutter!';
-    tester.binding.defaultBinaryMessenger
+    SystemChannels.platform
-      .setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+      .setMockMethodCallHandler((MethodCall methodCall) async {
         if (methodCall.method == 'Clipboard.getData')
           return <String, dynamic>{'text': clipboardContent};
         return null;
@@ -4893,8 +4883,8 @@ void main() {
         maxLines: 3,
       );
     String clipboardContent = '';
-    tester.binding.defaultBinaryMessenger
+    SystemChannels.platform
-      .setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+      .setMockMethodCallHandler((MethodCall methodCall) async {
         if (methodCall.method == 'Clipboard.setData')
           clipboardContent = methodCall.arguments['text'] as String;
         else if (methodCall.method == 'Clipboard.getData')
@@ -4967,8 +4957,8 @@ void main() {
       obscureText: true,
     );
     String clipboardContent = '';
-    tester.binding.defaultBinaryMessenger
+    SystemChannels.platform
-      .setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+      .setMockMethodCallHandler((MethodCall methodCall) async {
         if (methodCall.method == 'Clipboard.setData')
           clipboardContent = methodCall.arguments['text'] as String;
         else if (methodCall.method == 'Clipboard.getData')
@@ -9328,8 +9318,8 @@ void main() {
     );
 
     bool triedToReadClipboard = false;
-    tester.binding.defaultBinaryMessenger
+    SystemChannels.platform
-      .setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+      .setMockMethodCallHandler((MethodCall methodCall) async {
         if (methodCall.method == 'Clipboard.getData') {
           triedToReadClipboard = true;
         }

packages/flutter/test/material/text_form_field_test.dart

@@ -32,7 +32,7 @@ class MockClipboard {
 void main() {
   TestWidgetsFlutterBinding.ensureInitialized();
   final MockClipboard mockClipboard = MockClipboard();
-  TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, mockClipboard.handleMethodCall);
+  SystemChannels.platform.setMockMethodCallHandler(mockClipboard.handleMethodCall);
 
   setUp(() async {
     // Fill the clipboard so that the Paste option is available in the text

packages/flutter/test/material/text_selection_test.dart

@@ -28,7 +28,7 @@ class MockClipboard {
 void main() {
   TestWidgetsFlutterBinding.ensureInitialized();
   final MockClipboard mockClipboard = MockClipboard();
-  TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, mockClipboard.handleMethodCall);
+  SystemChannels.platform.setMockMethodCallHandler(mockClipboard.handleMethodCall);
 
   setUp(() async {
     await Clipboard.setData(const ClipboardData(text: 'clipboard data'));

packages/flutter/test/material/tooltip_test.dart

@@ -1193,7 +1193,7 @@ void main() {
 
   testWidgets('has semantic events', (WidgetTester tester) async {
     final List<dynamic> semanticEvents = <dynamic>[];
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, (dynamic message) async {
+    SystemChannels.accessibility.setMockMessageHandler((dynamic message) async {
       semanticEvents.add(message);
     });
     final SemanticsTester semantics = SemanticsTester(tester);
@@ -1230,7 +1230,7 @@ void main() {
       },
     ]));
     semantics.dispose();
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, null);
+    SystemChannels.accessibility.setMockMessageHandler(null);
   });
   testWidgets('default Tooltip debugFillProperties', (WidgetTester tester) async {
     final DiagnosticPropertiesBuilder builder = DiagnosticPropertiesBuilder();

packages/flutter/test/material/tooltip_theme_test.dart

@@ -1153,7 +1153,7 @@ void main() {
 
   testWidgets('has semantic events by default - ThemeData.tooltipTheme', (WidgetTester tester) async {
     final List<dynamic> semanticEvents = <dynamic>[];
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, (dynamic message) async {
+    SystemChannels.accessibility.setMockMessageHandler((dynamic message) async {
       semanticEvents.add(message);
     });
     final SemanticsTester semantics = SemanticsTester(tester);
@@ -1191,12 +1191,12 @@ void main() {
       },
     ]));
     semantics.dispose();
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, null);
+    SystemChannels.accessibility.setMockMessageHandler(null);
   });
 
   testWidgets('has semantic events by default - TooltipTheme', (WidgetTester tester) async {
     final List<dynamic> semanticEvents = <dynamic>[];
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, (dynamic message) async {
+    SystemChannels.accessibility.setMockMessageHandler((dynamic message) async {
       semanticEvents.add(message);
     });
     final SemanticsTester semantics = SemanticsTester(tester);
@@ -1236,7 +1236,7 @@ void main() {
       },
     ]));
     semantics.dispose();
-    tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, null);
+    SystemChannels.accessibility.setMockMessageHandler(null);
   });
 
   testWidgets('default Tooltip debugFillProperties', (WidgetTester tester) async {

packages/flutter/test/rendering/first_frame_test.dart

@@ -12,11 +12,11 @@ import 'package:flutter/services.dart';
 import 'package:flutter_test/flutter_test.dart';
 
 void main() {
-  final TestRenderBinding binding = TestRenderBinding();
   test('Flutter dispatches first frame event on the web only', () async {
     final Completer<void> completer = Completer<void>();
+    final TestRenderBinding binding = TestRenderBinding();
     const MethodChannel firstFrameChannel = MethodChannel('flutter/service_worker');
-    binding.defaultBinaryMessenger.setMockMethodCallHandler(firstFrameChannel, (MethodCall methodCall) async {
+    firstFrameChannel.setMockMethodCallHandler((MethodCall methodCall) async {
       completer.complete();
     });
 
@@ -27,10 +27,4 @@ void main() {
   }, skip: !kIsWeb);
 }
 
-class TestRenderBinding extends BindingBase
+class TestRenderBinding extends BindingBase with SchedulerBinding, ServicesBinding, GestureBinding, SemanticsBinding, RendererBinding {}
-  with SchedulerBinding,
-       ServicesBinding,
-       GestureBinding,
-       SemanticsBinding,
-       RendererBinding,
-       TestDefaultBinaryMessengerBinding { }

packages/flutter/test/rendering/mouse_tracker_cursor_test.dart

@@ -56,14 +56,14 @@ void main() {
 
   setUp(() {
     _binding.postFrameCallbacks.clear();
-    _binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.mouseCursor, (MethodCall call) async {
+    SystemChannels.mouseCursor.setMockMethodCallHandler((MethodCall call) async {
       if (_methodCallHandler != null)
         return _methodCallHandler!(call);
     });
   });
 
   tearDown(() {
-    _binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.mouseCursor, null);
+    SystemChannels.mouseCursor.setMockMethodCallHandler(null);
   });
 
   test('Should work on platforms that does not support mouse cursor', () async {

packages/flutter/test/rendering/mouse_tracker_test_utils.dart

@@ -9,7 +9,6 @@ import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart';
 import 'package:flutter/services.dart';
-import 'package:flutter_test/flutter_test.dart' show TestDefaultBinaryMessengerBinding;
 
 class _TestHitTester extends RenderBox {
   _TestHitTester(this.hitTestOverride);
@@ -25,7 +24,7 @@ class _TestHitTester extends RenderBox {
 // A binding used to test MouseTracker, allowing the test to override hit test
 // searching.
 class TestMouseTrackerFlutterBinding extends BindingBase
-    with SchedulerBinding, ServicesBinding, GestureBinding, SemanticsBinding, RendererBinding, TestDefaultBinaryMessengerBinding {
+    with SchedulerBinding, ServicesBinding, GestureBinding, SemanticsBinding, RendererBinding {
   @override
   void initInstances() {
     super.initInstances();

packages/flutter/test/rendering/rendering_tester.dart

@@ -9,12 +9,12 @@ import 'package:flutter/gestures.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/scheduler.dart';
 import 'package:flutter/services.dart';
-import 'package:flutter_test/flutter_test.dart' show TestDefaultBinaryMessengerBinding, EnginePhase, fail;
+import 'package:flutter_test/flutter_test.dart' show EnginePhase, fail;
 
 export 'package:flutter/foundation.dart' show FlutterError, FlutterErrorDetails;
-export 'package:flutter_test/flutter_test.dart' show TestDefaultBinaryMessengerBinding, EnginePhase;
+export 'package:flutter_test/flutter_test.dart' show EnginePhase;
 
-class TestRenderingFlutterBinding extends BindingBase with SchedulerBinding, ServicesBinding, GestureBinding, PaintingBinding, SemanticsBinding, RendererBinding, TestDefaultBinaryMessengerBinding {
+class TestRenderingFlutterBinding extends BindingBase with SchedulerBinding, ServicesBinding, GestureBinding, PaintingBinding, SemanticsBinding, RendererBinding {
   /// Creates a binding for testing rendering library functionality.
   ///
   /// If [onErrors] is not null, it is called if [FlutterError] caught any errors

packages/flutter/test/semantics/semantics_service_test.dart

@@ -13,13 +13,12 @@ void main() {
 
   test('Semantic announcement', () async {
     final List<Map<dynamic, dynamic>> log = <Map<dynamic, dynamic>>[];
-
     Future<dynamic> handleMessage(dynamic mockMessage) async {
       final Map<dynamic, dynamic> message = mockMessage as Map<dynamic, dynamic>;
       log.add(message);
     }
 
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockDecodedMessageHandler<dynamic>(SystemChannels.accessibility, handleMessage);
+    SystemChannels.accessibility.setMockMessageHandler(handleMessage);
 
     await SemanticsService.announce('announcement 1', TextDirection.ltr);
     await SemanticsService.announce('announcement 2', TextDirection.rtl);

packages/flutter/test/services/autofill_test.dart

@@ -191,6 +191,15 @@ class FakeTextChannel implements MethodChannel {
     incoming = handler;
   }
 
+  @override
+  bool checkMethodCallHandler(Future<void> Function(MethodCall call)? handler) => throw UnimplementedError();
+
+  @override
+  void setMockMethodCallHandler(Future<void>? Function(MethodCall call)? handler)  => throw UnimplementedError();
+
+  @override
+  bool checkMockMethodCallHandler(Future<void> Function(MethodCall call)? handler) => throw UnimplementedError();
+
   void validateOutgoingMethodCalls(List<MethodCall> calls) {
     expect(outgoingCalls.length, calls.length);
     bool hasError = false;

packages/flutter/test/services/binding_test.dart

@@ -30,7 +30,7 @@ L2Paragraph2
 
 L2Paragraph3''';
 
-const String combinedLicenses = '''
+const String licenses = '''
 $license1
 --------------------------------------------------------------------------------
 $license2
@@ -38,22 +38,20 @@ $license2
 
 class TestBinding extends BindingBase with SchedulerBinding, ServicesBinding {
   @override
-  TestDefaultBinaryMessenger get defaultBinaryMessenger => super.defaultBinaryMessenger as TestDefaultBinaryMessenger;
+  BinaryMessenger createBinaryMessenger() {
-
+    return super.createBinaryMessenger()
-  @override
+      ..setMockMessageHandler('flutter/assets', (ByteData? message) async {
-  TestDefaultBinaryMessenger createBinaryMessenger() {
+        if (const StringCodec().decodeMessage(message) == 'NOTICES') {
-    return TestDefaultBinaryMessenger(super.createBinaryMessenger());
+          return const StringCodec().encodeMessage(licenses);
+        }
+        return null;
+      });
   }
 }
 
 void main() {
   test('Adds rootBundle LICENSES to LicenseRegistry', () async {
-    TestBinding().defaultBinaryMessenger.setMockMessageHandler('flutter/assets', (ByteData? message) async {
+    TestBinding(); // The test binding registers a mock handler that returns licenses for the LICENSE key
-      if (const StringCodec().decodeMessage(message) == 'NOTICES') {
-        return const StringCodec().encodeMessage(combinedLicenses);
-      }
-      return null;
-    });
 
     final List<LicenseEntry> licenses = await LicenseRegistry.licenses.toList();
 

packages/flutter/test/services/default_binary_messenger_test.dart

@@ -2,10 +2,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'dart:async';
 import 'dart:convert';
 import 'dart:typed_data';
-
+import 'dart:ui' as ui;
 import 'package:flutter/services.dart';
 import 'package:flutter_test/flutter_test.dart';
 
@@ -20,39 +19,36 @@ void main() {
   }
 
   test('default binary messenger calls callback once', () async {
-    int countInbound = 0;
+    int count = 0;
-    int countOutbound = 0;
     const String channel = 'foo';
-    final ByteData bar = _makeByteData('bar');
+    ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
-    final Completer<void> done = Completer<void>();
-    ServicesBinding.instance!.channelBuffers.push(
       channel,
-      bar,
+      _makeByteData('bar'),
       (ByteData? message) async {
-        expect(message, isNull);
+        count += 1;
-        countOutbound += 1;
-        done.complete();
       },
     );
-    expect(countInbound, equals(0));
+    expect(count, equals(0));
-    expect(countOutbound, equals(0));
+    await ui.channelBuffers.drain(channel, (ByteData? data, ui.PlatformMessageResponseCallback callback) async {
-    ServicesBinding.instance!.defaultBinaryMessenger.setMessageHandler(
+      callback(null);
-      channel,
+    });
-      (ByteData? message) async {
+    expect(count, equals(1));
-        expect(message, bar);
+  });
-        countInbound += 1;
+
-      },
+  test('can check the handler', () {
-    );
+    Future<ByteData> handler(ByteData? call) => Future<ByteData>.value(null);
-    expect(countInbound, equals(0));
+    final BinaryMessenger messenger = ServicesBinding.instance!.defaultBinaryMessenger;
-    expect(countOutbound, equals(0));
+
-    await done.future;
+    expect(messenger.checkMessageHandler('test_channel', null), true);
-    expect(countInbound, equals(1));
+    expect(messenger.checkMessageHandler('test_channel', handler), false);
-    expect(countOutbound, equals(1));
+    messenger.setMessageHandler('test_channel', handler);
+    expect(messenger.checkMessageHandler('test_channel', handler), true);
+    messenger.setMessageHandler('test_channel', null);
   });
 
   test('can check the mock handler', () {
     Future<ByteData> handler(ByteData? call) => Future<ByteData>.value(null);
-    final TestDefaultBinaryMessenger messenger = TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger;
+    final BinaryMessenger messenger = ServicesBinding.instance!.defaultBinaryMessenger;
 
     expect(messenger.checkMockMessageHandler('test_channel', null), true);
     expect(messenger.checkMockMessageHandler('test_channel', handler), false);

packages/flutter/test/services/deferred_component_test.dart

@@ -11,7 +11,7 @@ void main() {
   test('installDeferredComponent test', () async {
     final List<MethodCall> log = <MethodCall>[];
 
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.deferredComponent, (MethodCall methodCall) async {
+    SystemChannels.deferredComponent.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -27,7 +27,7 @@ void main() {
   test('uninstallDeferredComponent test', () async {
     final List<MethodCall> log = <MethodCall>[];
 
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.deferredComponent, (MethodCall methodCall) async {
+    SystemChannels.deferredComponent.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 

packages/flutter/test/services/fake_platform_views.dart

@@ -8,7 +8,6 @@ import 'dart:typed_data';
 import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';
-import 'package:flutter_test/flutter_test.dart';
 
 /// Used in internal testing.
 class FakePlatformViewController extends PlatformViewController {
@@ -123,7 +122,7 @@ class FakeAndroidViewController implements AndroidViewController {
 
 class FakeAndroidPlatformViewsController {
   FakeAndroidPlatformViewsController() {
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform_views, _onMethodCall);
+    SystemChannels.platform_views.setMockMethodCallHandler(_onMethodCall);
   }
 
   Iterable<FakeAndroidPlatformView> get views => _views.values;
@@ -302,7 +301,7 @@ class FakeAndroidPlatformViewsController {
 
 class FakeIosPlatformViewsController {
   FakeIosPlatformViewsController() {
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform_views, _onMethodCall);
+    SystemChannels.platform_views.setMockMethodCallHandler(_onMethodCall);
   }
 
   Iterable<FakeUiKitView> get views => _views.values;
@@ -397,7 +396,7 @@ class FakeIosPlatformViewsController {
 
 class FakeHtmlPlatformViewsController {
   FakeHtmlPlatformViewsController() {
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform_views, _onMethodCall);
+    SystemChannels.platform_views.setMockMethodCallHandler(_onMethodCall);
   }
 
   Iterable<FakeHtmlPlatformView> get views => _views.values;

packages/flutter/test/services/haptic_feedback_test.dart

@@ -11,7 +11,7 @@ void main() {
   test('Haptic feedback control test', () async {
     final List<MethodCall> log = <MethodCall>[];
 
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -25,7 +25,7 @@ void main() {
     Future<void> callAndVerifyHapticFunction(Function hapticFunction, String platformMethodArgument) async {
       final List<MethodCall> log = <MethodCall>[];
 
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+      SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
         log.add(methodCall);
       });
 

packages/flutter/test/services/platform_channel_test.dart

@@ -12,7 +12,7 @@ void main() {
     const MessageCodec<String?> string = StringCodec();
     const BasicMessageChannel<String?> channel = BasicMessageChannel<String?>('ch', string);
     test('can send string message and get reply', () async {
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
         'ch',
         (ByteData? message) async => string.encodeMessage(string.decodeMessage(message)! + ' world'),
       );
@@ -23,7 +23,7 @@ void main() {
     test('can receive string message and send reply', () async {
       channel.setMessageHandler((String? message) async => message! + ' world');
       String? reply;
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         'ch',
         const StringCodec().encodeMessage('hello'),
         (ByteData? replyBinary) {
@@ -40,7 +40,7 @@ void main() {
     const MethodChannel channel = MethodChannel('ch7', jsonMethod);
     const OptionalMethodChannel optionalMethodChannel = OptionalMethodChannel('ch8', jsonMethod);
     test('can invoke method and get result', () async {
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
         'ch7',
         (ByteData? message) async {
           final Map<dynamic, dynamic> methodCall = jsonMessage.decodeMessage(message) as Map<dynamic, dynamic>;
@@ -56,7 +56,7 @@ void main() {
     });
 
     test('can invoke list method and get result', () async {
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
         'ch7',
         (ByteData? message) async {
           final Map<dynamic, dynamic> methodCall = jsonMessage.decodeMessage(message) as Map<dynamic, dynamic>;
@@ -72,7 +72,7 @@ void main() {
     });
 
     test('can invoke list method and get null result', () async {
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
         'ch7',
         (ByteData? message) async {
           final Map<dynamic, dynamic> methodCall = jsonMessage.decodeMessage(message) as Map<dynamic, dynamic>;
@@ -87,7 +87,7 @@ void main() {
     });
 
     test('can invoke map method and get result', () async {
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
         'ch7',
         (ByteData? message) async {
           final Map<dynamic, dynamic> methodCall = jsonMessage.decodeMessage(message) as Map<dynamic, dynamic>;
@@ -103,7 +103,7 @@ void main() {
     });
 
     test('can invoke map method and get null result', () async {
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
         'ch7',
         (ByteData? message) async {
           final Map<dynamic, dynamic> methodCall = jsonMessage.decodeMessage(message) as Map<dynamic, dynamic>;
@@ -118,7 +118,7 @@ void main() {
     });
 
     test('can invoke method and get error', () async {
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
         'ch7',
         (ByteData? message) async {
           return jsonMessage.encodeMessage(<dynamic>[
@@ -141,7 +141,7 @@ void main() {
     });
 
     test('can invoke unimplemented method', () async {
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
         'ch7',
         (ByteData? message) async => null,
       );
@@ -157,7 +157,7 @@ void main() {
     });
 
     test('can invoke unimplemented method (optional)', () async {
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
         'ch8',
         (ByteData? message) async => null,
       );
@@ -169,7 +169,7 @@ void main() {
       channel.setMethodCallHandler(null);
       final ByteData call = jsonMethod.encodeMethodCall(const MethodCall('sayHello', 'hello'));
       ByteData? envelope;
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage('ch7', call, (ByteData? result) {
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage('ch7', call, (ByteData? result) {
         envelope = result;
       });
       await null; // just in case there's something async happening
@@ -179,7 +179,7 @@ void main() {
     test('can handle method call with no registered plugin (setting after)', () async {
       final ByteData call = jsonMethod.encodeMethodCall(const MethodCall('sayHello', 'hello'));
       ByteData? envelope;
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage('ch7', call, (ByteData? result) {
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage('ch7', call, (ByteData? result) {
         envelope = result;
       });
       channel.setMethodCallHandler(null);
@@ -193,7 +193,7 @@ void main() {
       });
       final ByteData call = jsonMethod.encodeMethodCall(const MethodCall('sayHello', 'hello'));
       ByteData? envelope;
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage('ch7', call, (ByteData? result) {
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage('ch7', call, (ByteData? result) {
         envelope = result;
       });
       expect(envelope, isNull);
@@ -203,7 +203,7 @@ void main() {
       channel.setMethodCallHandler((MethodCall call) async => '${call.arguments}, world');
       final ByteData call = jsonMethod.encodeMethodCall(const MethodCall('sayHello', 'hello'));
       ByteData? envelope;
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage('ch7', call, (ByteData? result) {
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage('ch7', call, (ByteData? result) {
         envelope = result;
       });
       expect(jsonMethod.decodeEnvelope(envelope!), equals('hello, world'));
@@ -215,7 +215,7 @@ void main() {
       });
       final ByteData call = jsonMethod.encodeMethodCall(const MethodCall('sayHello', 'hello'));
       ByteData? envelope;
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage('ch7', call, (ByteData? result) {
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage('ch7', call, (ByteData? result) {
         envelope = result;
       });
       try {
@@ -235,7 +235,7 @@ void main() {
       });
       final ByteData call = jsonMethod.encodeMethodCall(const MethodCall('sayHello', 'hello'));
       ByteData? envelope;
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage('ch7', call, (ByteData? result) {
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage('ch7', call, (ByteData? result) {
         envelope = result;
       });
       try {
@@ -249,14 +249,24 @@ void main() {
       }
     });
 
-    test('can check the mock handler', () async {
+    test('can check the handler', () {
       Future<dynamic> handler(MethodCall call) => Future<dynamic>.value(null);
 
       const MethodChannel channel = MethodChannel('test_handler');
-      expect(TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.checkMockMessageHandler(channel.name, null), true);
+      expect(channel.checkMethodCallHandler(null), true);
-      expect(TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.checkMockMessageHandler(channel.name, handler), false);
+      expect(channel.checkMethodCallHandler(handler), false);
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(channel, handler);
+      channel.setMethodCallHandler(handler);
-      expect(TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.checkMockMessageHandler(channel.name, handler), true);
+      expect(channel.checkMethodCallHandler(handler), true);
+    });
+
+    test('can check the mock handler', () {
+      Future<dynamic> handler(MethodCall call) => Future<dynamic>.value(null);
+
+      const MethodChannel channel = MethodChannel('test_handler');
+      expect(channel.checkMockMethodCallHandler(null), true);
+      expect(channel.checkMockMethodCallHandler(handler), false);
+      channel.setMockMethodCallHandler(handler);
+      expect(channel.checkMockMethodCallHandler(handler), true);
     });
   });
 
@@ -265,7 +275,7 @@ void main() {
     const MethodCodec jsonMethod = JSONMethodCodec();
     const EventChannel channel = EventChannel('ch', jsonMethod);
     void emitEvent(ByteData? event) {
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         'ch',
         event,
         (ByteData? reply) {},
@@ -273,7 +283,7 @@ void main() {
     }
     test('can receive event stream', () async {
       bool canceled = false;
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
         'ch',
         (ByteData? message) async {
           final Map<dynamic, dynamic> methodCall = jsonMessage.decodeMessage(message) as Map<dynamic, dynamic>;
@@ -298,7 +308,7 @@ void main() {
     });
 
     test('can receive error event', () async {
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
         'ch',
         (ByteData? message) async {
           final Map<dynamic, dynamic> methodCall = jsonMessage.decodeMessage(message) as Map<dynamic, dynamic>;

packages/flutter/test/services/platform_messages_test.dart

@@ -7,23 +7,24 @@ import 'package:flutter/services.dart';
 import 'package:flutter_test/flutter_test.dart';
 
 void main() {
-  TestWidgetsFlutterBinding.ensureInitialized();
-
   test('Mock binary message handler control test', () async {
+    // Initialize all bindings because defaultBinaryMessenger.send() needs a window.
+    TestWidgetsFlutterBinding.ensureInitialized();
+
     final List<ByteData?> log = <ByteData>[];
 
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler('test1', (ByteData? message) async {
+    ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler('test1', (ByteData? message) async {
       log.add(message);
       return null;
     });
 
     final ByteData message = ByteData(2)..setUint16(0, 0xABCD);
-    await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.send('test1', message);
+    await ServicesBinding.instance!.defaultBinaryMessenger.send('test1', message);
     expect(log, equals(<ByteData>[message]));
     log.clear();
 
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler('test1', null);
+    ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler('test1', null);
-    await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.send('test1', message);
+    await ServicesBinding.instance!.defaultBinaryMessenger.send('test1', message);
     expect(log, isEmpty);
   });
 }

packages/flutter/test/services/raw_keyboard_test.dart

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+
 import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';
@@ -29,7 +30,6 @@ void main() {
         RawKeyboard.instance.removeListener(handleKey);
       }
     });
-
     testWidgets('No character is produced for non-printables', (WidgetTester tester) async {
       for (final String platform in <String>['linux', 'android', 'macos', 'fuchsia', 'windows', 'web']) {
         void handleKey(RawKeyEvent event) {
@@ -40,7 +40,6 @@ void main() {
         RawKeyboard.instance.removeListener(handleKey);
       }
     });
-
     testWidgets('keysPressed is maintained', (WidgetTester tester) async {
       for (final String platform in <String>['linux', 'android', 'macos', 'fuchsia', 'windows', 'ios']) {
         RawKeyboard.instance.clearKeysPressed();
@@ -210,7 +209,7 @@ void main() {
       // when this event is received, but it's not in keysPressed yet.
       data['modifiers'] |= RawKeyEventDataMacOs.modifierLeftShift | RawKeyEventDataMacOs.modifierShift;
       // dispatch the modified data.
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
         (ByteData? data) {},
@@ -235,7 +234,7 @@ void main() {
       // when this event is received, but it's not in keysPressed yet.
       data['modifiers'] |= RawKeyEventDataMacOs.modifierLeftShift | RawKeyEventDataMacOs.modifierShift;
       // dispatch the modified data.
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
         (ByteData? data) {},
@@ -260,7 +259,7 @@ void main() {
       // when this event is received, but it's not in keysPressed yet.
       data['modifiers'] |= RawKeyEventDataWindows.modifierLeftShift | RawKeyEventDataWindows.modifierShift;
       // dispatch the modified data.
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
         (ByteData? data) {},
@@ -285,7 +284,7 @@ void main() {
       // when this event is received, but it's not in keysPressed yet.
       data['metaState'] |= RawKeyEventDataAndroid.modifierLeftShift | RawKeyEventDataAndroid.modifierShift;
       // dispatch the modified data.
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
         (ByteData? data) {},
@@ -310,7 +309,7 @@ void main() {
       // when this event is received, but it's not in keysPressed yet.
       data['modifiers'] |= RawKeyEventDataFuchsia.modifierLeftShift;
       // dispatch the modified data.
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
         (ByteData? data) {},
@@ -335,7 +334,7 @@ void main() {
       // when this event is received, but it's not in keysPressed yet.
       data['modifiers'] |= GLFWKeyHelper.modifierShift;
       // dispatch the modified data.
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
         (ByteData? data) {},
@@ -365,7 +364,7 @@ void main() {
         isDown: true,
       )..['metaState'] |= RawKeyEventDataWeb.modifierShift;
       // Dispatch the modified data.
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
         (ByteData? data) {},
@@ -457,7 +456,7 @@ void main() {
         RawKeyEventDataAndroid.modifierControl |
         RawKeyEventDataAndroid.modifierMeta;
       // dispatch the modified data.
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
             (ByteData? data) {},
@@ -495,7 +494,7 @@ void main() {
           RawKeyEventDataMacOs.modifierCommand |
           RawKeyEventDataMacOs.modifierControl;
       // dispatch the modified data.
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
             (ByteData? data) {},
@@ -571,7 +570,7 @@ void main() {
           RawKeyEventDataWindows.modifierAlt |
           RawKeyEventDataWindows.modifierControl;
       // dispatch the modified data.
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
             (ByteData? data) {},
@@ -608,7 +607,7 @@ void main() {
         GLFWKeyHelper.modifierControl |
         GLFWKeyHelper.modifierMeta;
       // dispatch the modified data.
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
             (ByteData? data) {},
@@ -646,7 +645,7 @@ void main() {
         RawKeyEventDataWeb.modifierControl |
         RawKeyEventDataWeb.modifierMeta;
       // dispatch the modified data.
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
             (ByteData? data) {},
@@ -666,6 +665,12 @@ void main() {
     });
 
     testWidgets('RawKeyboard asserts if no keys are in keysPressed after receiving a key down event', (WidgetTester tester) async {
+      FlutterErrorDetails? errorDetails;
+      final FlutterExceptionHandler? oldHandler = FlutterError.onError;
+      FlutterError.onError = (FlutterErrorDetails details) {
+        errorDetails = details;
+      };
+
       final Map<String, dynamic> keyEventMessage;
       if (kIsWeb) {
         keyEventMessage = const <String, dynamic>{
@@ -687,15 +692,19 @@ void main() {
       }
 
       try {
-        await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+        await ServicesBinding.instance!.defaultBinaryMessenger
+            .handlePlatformMessage(
           SystemChannels.keyEvent.name,
           SystemChannels.keyEvent.codec.encodeMessage(keyEventMessage),
-          (ByteData? data) { },
+              (ByteData? data) {},
         );
-        fail('Expected an exception, but did not get one.');
+      } finally {
-      } on AssertionError catch (error) {
+        FlutterError.onError = oldHandler;
-        expect(error.toString(), contains('Attempted to send a key down event when no keys are in keysPressed'));
       }
+      expect(errorDetails, isNotNull);
+      expect(errorDetails!.stack, isNotNull);
+      final String fullErrorMessage = errorDetails.toString().replaceAll('\n', ' ');
+      expect(fullErrorMessage, contains('Attempted to send a key down event when no keys are in keysPressed'));
     });
   });
 
@@ -748,7 +757,6 @@ void main() {
         }
       }
     });
-
     test('modifier keys are recognized when combined', () {
       for (final int modifier in modifierTests.keys) {
         if (modifier == RawKeyEventDataAndroid.modifierFunction) {
@@ -791,7 +799,6 @@ void main() {
         }
       }
     });
-
     test('Printable keyboard keys are correctly translated', () {
       final RawKeyEvent keyAEvent = RawKeyEvent.fromMessage(<String, dynamic>{
         'type': 'keydown',
@@ -810,7 +817,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.keyA));
       expect(data.keyLabel, equals('a'));
     });
-
     test('Control keyboard keys are correctly translated', () {
       final RawKeyEvent escapeKeyEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -827,7 +833,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.escape));
       expect(data.keyLabel, isEmpty);
     });
-
     test('Modifier keyboard keys are correctly translated', () {
       final RawKeyEvent shiftLeftKeyEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -845,7 +850,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.shiftLeft));
       expect(data.keyLabel, isEmpty);
     });
-
     test('DPAD keys from a joystick give physical key mappings', () {
       final RawKeyEvent joystickDpadDown = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -863,7 +867,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.arrowDown));
       expect(data.keyLabel, isEmpty);
     });
-
     test('Arrow keys from a keyboard give correct physical key mappings', () {
       final RawKeyEvent joystickDpadDown = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -880,7 +883,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.arrowDown));
       expect(data.keyLabel, isEmpty);
     });
-
     test('DPAD center from a game pad gives physical key mappings', () {
       final RawKeyEvent joystickDpadCenter = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -898,7 +900,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.select));
       expect(data.keyLabel, isEmpty);
     });
-
     test('Device id is read from message', () {
       final RawKeyEvent joystickDpadCenter = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -914,7 +915,6 @@ void main() {
       final RawKeyEventDataAndroid data = joystickDpadCenter.data as RawKeyEventDataAndroid;
       expect(data.deviceId, equals(10));
     });
-
     test('Repeat count is passed correctly', () {
       final RawKeyEvent repeatCountEvent = RawKeyEvent.fromMessage(<String, dynamic>{
         'type': 'keydown',
@@ -931,7 +931,6 @@ void main() {
       final RawKeyEventDataAndroid data = repeatCountEvent.data as RawKeyEventDataAndroid;
       expect(data.repeatCount, equals(42));
     });
-
     testWidgets('Key events are responded to correctly.', (WidgetTester tester) async {
       expect(RawKeyboard.instance.keysPressed, isEmpty);
       // Generate the data for a regular key down event.
@@ -941,7 +940,7 @@ void main() {
         isDown: true,
       );
       Map<String, dynamic>? message;
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
         (ByteData? data) {
@@ -964,7 +963,7 @@ void main() {
       focusNode.requestFocus();
       await tester.pump();
 
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
         (ByteData? data) {
@@ -972,7 +971,7 @@ void main() {
         },
       );
       expect(message, equals(<String, dynamic>{ 'handled': true }));
-      tester.binding.defaultBinaryMessenger.setMockMessageHandler(SystemChannels.keyEvent.name, null);
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(SystemChannels.keyEvent.name, null);
     });
   }, skip: isBrowser); // This is an Android-specific group.
 
@@ -1020,7 +1019,6 @@ void main() {
         }
       }
     });
-
     test('modifier keys are recognized when combined', () {
       for (final int modifier in modifierTests.keys) {
         if (modifier == RawKeyEventDataFuchsia.modifierCapsLock) {
@@ -1054,7 +1052,6 @@ void main() {
         }
       }
     });
-
     test('Printable keyboard keys are correctly translated', () {
       final RawKeyEvent keyAEvent = RawKeyEvent.fromMessage(<String, dynamic>{
         'type': 'keydown',
@@ -1068,7 +1065,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.keyA));
       expect(data.keyLabel, equals('a'));
     });
-
     test('Control keyboard keys are correctly translated', () {
       final RawKeyEvent escapeKeyEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -1140,7 +1136,6 @@ void main() {
         }
       }
     });
-
     test('modifier keys are recognized when combined', () {
       for (final int modifier in modifierTests.keys) {
         if (modifier == RawKeyEventDataMacOs.modifierCapsLock) {
@@ -1180,7 +1175,6 @@ void main() {
         }
       }
     });
-
     test('Printable keyboard keys are correctly translated', () {
       const String unmodifiedCharacter = 'a';
       final RawKeyEvent keyAEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
@@ -1196,7 +1190,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.keyA));
       expect(data.keyLabel, equals('a'));
     });
-
     test('Control keyboard keys are correctly translated', () {
       final RawKeyEvent escapeKeyEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -1288,7 +1281,6 @@ void main() {
         }
       }
     });
-
     test('modifier keys are recognized when combined', () {
       for (final int modifier in modifierTests.keys) {
         if (modifier == RawKeyEventDataIos.modifierCapsLock) {
@@ -1328,7 +1320,6 @@ void main() {
         }
       }
     });
-
     test('Printable keyboard keys are correctly translated', () {
       const String unmodifiedCharacter = 'a';
       final RawKeyEvent keyAEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
@@ -1344,7 +1335,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.keyA));
       expect(data.keyLabel, equals('a'));
     });
-
     test('Control keyboard keys are correctly translated', () {
       final RawKeyEvent escapeKeyEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -1437,7 +1427,6 @@ void main() {
         }
       }
     });
-
     test('modifier keys are recognized when combined', () {
       for (final int modifier in modifierTests.keys) {
         if (modifier == RawKeyEventDataWindows.modifierCaps) {
@@ -1477,7 +1466,6 @@ void main() {
         }
       }
     });
-
     test('Printable keyboard keys are correctly translated', () {
       const int unmodifiedCharacter = 97; // ASCII value for 'a'.
       final RawKeyEvent keyAEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
@@ -1493,7 +1481,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.keyA));
       expect(data.keyLabel, equals('a'));
     });
-
     test('Control keyboard keys are correctly translated', () {
       final RawKeyEvent escapeKeyEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -1508,7 +1495,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.escape));
       expect(data.keyLabel, isEmpty);
     });
-
     test('Modifier keyboard keys are correctly translated', () {
       final RawKeyEvent shiftLeftKeyEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -1523,7 +1509,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.shiftLeft));
       expect(data.keyLabel, isEmpty);
     });
-
     test('Unprintable keyboard keys are correctly translated', () {
       final RawKeyEvent leftArrowKey = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -1537,7 +1522,6 @@ void main() {
       expect(data.physicalKey, equals(PhysicalKeyboardKey.arrowLeft));
       expect(data.logicalKey, equals(LogicalKeyboardKey.arrowLeft));
     });
-
     testWidgets('Win32 VK_PROCESSKEY events are skipped', (WidgetTester tester) async {
       const  String platform = 'windows';
       bool lastHandled = true;
@@ -1636,7 +1620,6 @@ void main() {
         }
       }
     });
-
     test('modifier keys are recognized when combined', () {
       for (final int modifier in modifierTests.keys) {
         if (modifier == GLFWKeyHelper.modifierControl) {
@@ -1677,7 +1660,6 @@ void main() {
         }
       }
     });
-
     test('Printable keyboard keys are correctly translated', () {
       final RawKeyEvent keyAEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -1693,7 +1675,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.keyQ));
       expect(data.keyLabel, equals('q'));
     });
-
     test('Code points with two Unicode scalar values are allowed', () {
       final RawKeyEvent keyAEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -1742,7 +1723,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.escape));
       expect(data.keyLabel, isEmpty);
     });
-
     test('Modifier keyboard keys are correctly translated', () {
       final RawKeyEvent shiftLeftKeyEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -1824,7 +1804,6 @@ void main() {
         }
       }
     });
-
     test('modifier keys are recognized when combined', () {
       for (final int modifier in modifierTests.keys) {
         if (modifier == GtkKeyHelper.modifierControl) {
@@ -1865,7 +1844,6 @@ void main() {
         }
       }
     });
-
     test('Printable keyboard keys are correctly translated', () {
       final RawKeyEvent keyAEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -1881,7 +1859,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.keyQ));
       expect(data.keyLabel, equals('q'));
     });
-
     test('Code points with two Unicode scalar values are allowed', () {
       final RawKeyEvent keyAEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -1930,7 +1907,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.escape));
       expect(data.keyLabel, isEmpty);
     });
-
     test('Modifier keyboard keys are correctly translated', () {
       final RawKeyEvent shiftLeftKeyEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -1984,7 +1960,6 @@ void main() {
         }
       }
     });
-
     test('modifier keys are recognized when combined', () {
       for (final int modifier in modifierTests.keys) {
         if (modifier == RawKeyEventDataWeb.modifierMeta) {
@@ -2017,7 +1992,6 @@ void main() {
         }
       }
     });
-
     test('Printable keyboard keys are correctly translated', () {
       final RawKeyEvent keyAEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -2031,7 +2005,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.keyA));
       expect(data.keyLabel, equals('a'));
     });
-
     test('Control keyboard keys are correctly translated', () {
       final RawKeyEvent escapeKeyEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -2044,7 +2017,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.escape));
       expect(data.keyLabel, isEmpty);
     });
-
     test('Modifier keyboard keys are correctly translated', () {
       final RawKeyEvent shiftKeyEvent = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',
@@ -2057,7 +2029,6 @@ void main() {
       expect(data.logicalKey, equals(LogicalKeyboardKey.shiftLeft));
       expect(data.keyLabel, isEmpty);
     });
-
     test('Arrow keys from a keyboard give correct physical key mappings', () {
       final RawKeyEvent arrowKeyDown = RawKeyEvent.fromMessage(const <String, dynamic>{
         'type': 'keydown',

packages/flutter/test/services/restoration_test.dart

@@ -18,7 +18,7 @@ void main() {
     testWidgets('root bucket retrieval', (WidgetTester tester) async {
       final List<MethodCall> callsToEngine = <MethodCall>[];
       final Completer<Map<dynamic, dynamic>> result = Completer<Map<dynamic, dynamic>>();
-      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.restoration, (MethodCall call) {
+      SystemChannels.restoration.setMockMethodCallHandler((MethodCall call) {
         callsToEngine.add(call);
         return result.future;
       });
@@ -64,7 +64,7 @@ void main() {
     testWidgets('root bucket received from engine before retrieval', (WidgetTester tester) async {
       SystemChannels.restoration.setMethodCallHandler(null);
       final List<MethodCall> callsToEngine = <MethodCall>[];
-      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.restoration, (MethodCall call) async {
+      SystemChannels.restoration.setMockMethodCallHandler((MethodCall call) async {
         callsToEngine.add(call);
       });
       final RestorationManager manager = RestorationManager();
@@ -83,7 +83,7 @@ void main() {
       SystemChannels.restoration.setMethodCallHandler(null);
       final List<MethodCall> callsToEngine = <MethodCall>[];
       final Completer<Map<dynamic, dynamic>> result = Completer<Map<dynamic, dynamic>>();
-      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.restoration, (MethodCall call) {
+      SystemChannels.restoration.setMockMethodCallHandler((MethodCall call) {
         callsToEngine.add(call);
         return result.future;
       });
@@ -110,7 +110,7 @@ void main() {
     });
 
     testWidgets('root bucket is properly replaced when new data is available', (WidgetTester tester) async {
-      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.restoration, (MethodCall call) async {
+      SystemChannels.restoration.setMockMethodCallHandler((MethodCall call) async {
         return _createEncodedRestorationData1();
       });
       final RestorationManager manager = RestorationManager();
@@ -152,7 +152,7 @@ void main() {
     testWidgets('returns null as root bucket when restoration is disabled', (WidgetTester tester) async {
       final List<MethodCall> callsToEngine = <MethodCall>[];
       final Completer<Map<dynamic, dynamic>> result = Completer<Map<dynamic, dynamic>>();
-      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.restoration, (MethodCall call)  {
+      SystemChannels.restoration.setMockMethodCallHandler((MethodCall call)  {
         callsToEngine.add(call);
         return result.future;
       });
@@ -195,7 +195,7 @@ void main() {
     testWidgets('flushData', (WidgetTester tester) async {
       final List<MethodCall> callsToEngine = <MethodCall>[];
       final Completer<Map<dynamic, dynamic>> result = Completer<Map<dynamic, dynamic>>();
-      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.restoration, (MethodCall call) {
+      SystemChannels.restoration.setMockMethodCallHandler((MethodCall call) {
         callsToEngine.add(call);
         return result.future;
       });
@@ -230,7 +230,7 @@ void main() {
 
     testWidgets('isReplacing', (WidgetTester tester) async {
       final Completer<Map<dynamic, dynamic>> result = Completer<Map<dynamic, dynamic>>();
-      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.restoration, (MethodCall call) {
+      SystemChannels.restoration.setMockMethodCallHandler((MethodCall call) {
         return result.future;
       });
 

packages/flutter/test/services/system_chrome_test.dart

@@ -7,8 +7,6 @@ import 'package:flutter/services.dart';
 import 'package:flutter_test/flutter_test.dart';
 
 void main() {
-  TestWidgetsFlutterBinding.ensureInitialized();
-
   testWidgets('SystemChrome overlay style test', (WidgetTester tester) async {
     // The first call is a cache miss and will queue a microtask
     SystemChrome.setSystemUIOverlayStyle(SystemUiOverlayStyle.light);
@@ -26,7 +24,7 @@ void main() {
   test('setPreferredOrientations control test', () async {
     final List<MethodCall> log = <MethodCall>[];
 
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -44,7 +42,7 @@ void main() {
   test('setApplicationSwitcherDescription control test', () async {
     final List<MethodCall> log = <MethodCall>[];
 
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -62,7 +60,7 @@ void main() {
   test('setApplicationSwitcherDescription missing plugin', () async {
     final List<ByteData?> log = <ByteData>[];
 
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler('flutter/platform', (ByteData? message) async {
+    ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler('flutter/platform', (ByteData? message) async {
       log.add(message);
     });
 
@@ -76,7 +74,7 @@ void main() {
   test('setEnabledSystemUIOverlays control test', () async {
     final List<MethodCall> log = <MethodCall>[];
 
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 

packages/flutter/test/services/system_navigator_test.dart

@@ -12,7 +12,7 @@ void main() {
   test('System navigator control test', () async {
     final List<MethodCall> log = <MethodCall>[];
 
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 

packages/flutter/test/services/system_sound_test.dart

@@ -12,7 +12,7 @@ void main() {
   test('System sound control test', () async {
     final List<MethodCall> log = <MethodCall>[];
 
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 

packages/flutter/test/services/text_input_test.dart

@@ -442,6 +442,16 @@ class FakeTextChannel implements MethodChannel {
   @override
   void setMethodCallHandler(Future<void> Function(MethodCall call)? handler) => incoming = handler;
 
+  @override
+  bool checkMethodCallHandler(Future<void> Function(MethodCall call)? handler) => throw UnimplementedError();
+
+
+  @override
+  void setMockMethodCallHandler(Future<void>? Function(MethodCall call)? handler)  => throw UnimplementedError();
+
+  @override
+  bool checkMockMethodCallHandler(Future<void> Function(MethodCall call)? handler) => throw UnimplementedError();
+
   void validateOutgoingMethodCalls(List<MethodCall> calls) {
     expect(outgoingCalls.length, calls.length);
     bool hasError = false;

packages/flutter/test/widgets/draggable_test.dart

@@ -3101,7 +3101,7 @@ Future<void> _testLongPressDraggableHapticFeedback({ required WidgetTester teste
   bool onDragStartedCalled = false;
 
   int hapticFeedbackCalls = 0;
-  tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+  SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
     if (methodCall.method == 'HapticFeedback.vibrate') {
       hapticFeedbackCalls++;
     }

packages/flutter/test/widgets/editable_text_cursor_test.dart

@@ -75,7 +75,7 @@ void main() {
 
     // Populate a fake clipboard.
     const String clipboardContent = ' ';
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       if (methodCall.method == 'Clipboard.getData')
         return const <String, dynamic>{'text': clipboardContent};
       return null;
@@ -127,7 +127,7 @@ void main() {
 
     // Populate a fake clipboard.
     const String clipboardContent = ' ';
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       if (methodCall.method == 'Clipboard.getData')
         return const <String, dynamic>{'text': clipboardContent};
       return null;
@@ -820,7 +820,7 @@ void main() {
 
     // Populate a fake clipboard.
     const String clipboardContent = 'Hello world!';
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       if (methodCall.method == 'Clipboard.getData')
         return const <String, dynamic>{'text': clipboardContent};
       return null;
@@ -878,7 +878,7 @@ void main() {
 
     // Populate a fake clipboard.
     const String clipboardContent = 'Hello world!';
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       if (methodCall.method == 'Clipboard.getData')
         return const <String, dynamic>{'text': clipboardContent};
       return null;

packages/flutter/test/widgets/editable_text_test.dart

@@ -65,9 +65,9 @@ class MockClipboard {
 }
 
 void main() {
+  TestWidgetsFlutterBinding.ensureInitialized();
   final MockClipboard mockClipboard = MockClipboard();
-  (TestWidgetsFlutterBinding.ensureInitialized() as TestWidgetsFlutterBinding)
+  SystemChannels.platform.setMockMethodCallHandler(mockClipboard.handleMethodCall);
-    .defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, mockClipboard.handleMethodCall);
 
   setUp(() async {
     debugResetSemanticsIdCounter();
@@ -1985,7 +1985,7 @@ void main() {
     await tester.pump(); // An extra pump to allow focus request to go through.
 
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall methodCall) async {
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -3176,7 +3176,7 @@ void main() {
     // Regression test for https://github.com/flutter/flutter/issues/22212.
 
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall methodCall) async {
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -3207,7 +3207,7 @@ void main() {
 
   testWidgets('location of widget is sent on show keyboard', (WidgetTester tester) async {
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall methodCall) async {
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -3244,7 +3244,7 @@ void main() {
 
   testWidgets('transform and size is reset when text connection opens', (WidgetTester tester) async {
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall methodCall) async {
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -3332,7 +3332,7 @@ void main() {
 
   testWidgets('size and transform are sent when they change', (WidgetTester tester) async {
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall methodCall) async {
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -3374,7 +3374,7 @@ void main() {
 
   testWidgets('text styling info is sent on show keyboard', (WidgetTester tester) async {
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall methodCall) async {
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -3461,7 +3461,7 @@ void main() {
     await tester.showKeyboard(find.byType(EditableText));
 
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall methodCall) async {
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
     setState(() {
@@ -3678,7 +3678,7 @@ void main() {
     // Regression test for https://github.com/flutter/flutter/issues/22212.
 
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall methodCall) async {
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -5639,7 +5639,7 @@ void main() {
   testWidgets('Synchronous test of local and remote editing values', (WidgetTester tester) async {
     // Regression test for https://github.com/flutter/flutter/issues/65059
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall methodCall) async {
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
     final TextInputFormatter formatter = TextInputFormatter.withFunction((TextEditingValue oldValue, TextEditingValue newValue) {
@@ -5767,7 +5767,7 @@ void main() {
   testWidgets('Send text input state to engine when the input formatter rejects user input', (WidgetTester tester) async {
     // Regression test for https://github.com/flutter/flutter/issues/67828
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall methodCall) async {
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
     final TextInputFormatter formatter = TextInputFormatter.withFunction((TextEditingValue oldValue, TextEditingValue newValue) {
@@ -5846,7 +5846,7 @@ void main() {
   testWidgets('Repeatedly receiving [TextEditingValue] will not trigger a keyboard request', (WidgetTester tester) async {
     // Regression test for https://github.com/flutter/flutter/issues/66036
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall methodCall) async {
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
     final TextEditingController controller = TextEditingController();
@@ -5967,7 +5967,7 @@ void main() {
     testWidgets('TextEditingController.clear() behavior test', (WidgetTester tester) async {
       // Regression test for https://github.com/flutter/flutter/issues/66316
       final List<MethodCall> log = <MethodCall>[];
-      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall methodCall) async {
+      SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
         log.add(methodCall);
       });
       final TextEditingController controller = TextEditingController();

packages/flutter/test/widgets/modal_barrier_test.dart

@@ -165,7 +165,7 @@ void main() {
   testWidgets('ModalBarrier plays system alert sound when user tries to dismiss it', (WidgetTester tester) async {
     final List<String> playedSystemSounds = <String>[];
     try {
-      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+      SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
         if (methodCall.method == 'SystemSound.play')
           playedSystemSounds.add(methodCall.arguments as String);
       });
@@ -182,7 +182,7 @@ void main() {
       await tester.tap(find.text('target'), warnIfMissed: false);
       await tester.pumpWidget(subject);
     } finally {
-      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, null);
+      SystemChannels.platform.setMockMethodCallHandler(null);
     }
     expect(playedSystemSounds, hasLength(1));
     expect(playedSystemSounds[0], SystemSoundType.alert.toString());

packages/flutter/test/widgets/mouse_region_test.dart

@@ -1588,7 +1588,7 @@ void main() {
     final TestGesture gesture = await tester.createGesture(kind: PointerDeviceKind.mouse);
     await gesture.addPointer(location: const Offset(100, 100));
     addTearDown(gesture.removePointer);
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.mouseCursor, (_) async {
+    SystemChannels.mouseCursor.setMockMethodCallHandler((_) async {
       logCursors.add('cursor');
     });
 

packages/flutter/test/widgets/platform_view_test.dart

@@ -1042,7 +1042,7 @@ void main() {
       await tester.pump();
 
       late int lastPlatformViewTextClient;
-      tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.textInput, (MethodCall call) {
+      SystemChannels.textInput.setMockMethodCallHandler((MethodCall call) {
         if (call.method == 'TextInput.setPlatformViewClient') {
           lastPlatformViewTextClient = call.arguments as int;
         }

packages/flutter/test/widgets/route_notification_messages_test.dart

@@ -53,7 +53,7 @@ void main() {
 
     final List<MethodCall> log = <MethodCall>[];
 
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.navigation, (MethodCall methodCall) async {
+    SystemChannels.navigation.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -105,7 +105,7 @@ void main() {
 
   testWidgets('Navigator does not report route name by default', (WidgetTester tester) async {
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.navigation, (MethodCall methodCall) async {
+    SystemChannels.navigation.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -153,7 +153,7 @@ void main() {
 
     final List<MethodCall> log = <MethodCall>[];
 
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.navigation, (MethodCall methodCall) async {
+    SystemChannels.navigation.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -205,7 +205,7 @@ void main() {
 
   testWidgets('Nameless routes should send platform messages', (WidgetTester tester) async {
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.navigation, (MethodCall methodCall) async {
+    SystemChannels.navigation.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 
@@ -252,7 +252,7 @@ void main() {
 
   testWidgets('PlatformRouteInformationProvider reports URL', (WidgetTester tester) async {
     final List<MethodCall> log = <MethodCall>[];
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.navigation, (MethodCall methodCall) async {
+    SystemChannels.navigation.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 

packages/flutter/test/widgets/selectable_text_test.dart

@@ -124,7 +124,7 @@ double getOpacity(WidgetTester tester, Finder finder) {
 void main() {
   TestWidgetsFlutterBinding.ensureInitialized();
   final MockClipboard mockClipboard = MockClipboard();
-  TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, mockClipboard.handleMethodCall);
+  SystemChannels.platform.setMockMethodCallHandler(mockClipboard.handleMethodCall);
 
   const String kThreeLines =
       'First line of text is\n'
@@ -1626,7 +1626,7 @@ void main() {
     final FocusNode focusNode = FocusNode();
 
     String clipboardContent = '';
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       if (methodCall.method == 'Clipboard.setData')
         clipboardContent = methodCall.arguments['text'] as String;
       else if (methodCall.method == 'Clipboard.getData')

packages/flutter/test/widgets/text_selection_test.dart

@@ -19,15 +19,15 @@ class MockClipboard {
     'text': null,
   };
 
-  Future<Object?> handleMethodCall(MethodCall methodCall) async {
+  Future<dynamic> handleMethodCall(MethodCall methodCall) async {
     switch (methodCall.method) {
       case 'Clipboard.getData':
-        if (getDataThrows)
+        if (getDataThrows) {
           throw Exception();
+        }
         return _clipboardData;
       case 'Clipboard.setData':
         _clipboardData = methodCall.arguments;
-        break;
     }
   }
 }
@@ -758,11 +758,11 @@ void main() {
     group('when Clipboard fails', () {
       setUp(() {
         final MockClipboard mockClipboard = MockClipboard(getDataThrows: true);
-        TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, mockClipboard.handleMethodCall);
+        SystemChannels.platform.setMockMethodCallHandler(mockClipboard.handleMethodCall);
       });
 
       tearDown(() {
-        TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, null);
+        SystemChannels.platform.setMockMethodCallHandler(null);
       });
 
       test('Clipboard API failure is gracefully recovered from', () async {
@@ -778,11 +778,11 @@ void main() {
       final MockClipboard mockClipboard = MockClipboard();
 
       setUp(() {
-        TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, mockClipboard.handleMethodCall);
+        SystemChannels.platform.setMockMethodCallHandler(mockClipboard.handleMethodCall);
       });
 
       tearDown(() {
-        TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, null);
+        SystemChannels.platform.setMockMethodCallHandler(null);
       });
 
       test('update sets value based on clipboard contents', () async {

packages/flutter/test/widgets/title_test.dart

@@ -36,7 +36,7 @@ void main() {
   testWidgets('should not pass "null" to setApplicationSwitcherDescription', (WidgetTester tester) async {
     final List<MethodCall> log = <MethodCall>[];
 
-    tester.binding.defaultBinaryMessenger.setMockMethodCallHandler(SystemChannels.platform, (MethodCall methodCall) async {
+    SystemChannels.platform.setMockMethodCallHandler((MethodCall methodCall) async {
       log.add(methodCall);
     });
 

packages/flutter_driver/lib/src/extension/extension.dart

@@ -30,7 +30,7 @@ const String _extensionMethodName = 'driver';
 /// eventually completes to a string response.
 typedef DataHandler = Future<String> Function(String? message);
 
-class _DriverBinding extends BindingBase with SchedulerBinding, ServicesBinding, GestureBinding, PaintingBinding, SemanticsBinding, RendererBinding, WidgetsBinding, TestDefaultBinaryMessengerBinding {
+class _DriverBinding extends BindingBase with SchedulerBinding, ServicesBinding, GestureBinding, PaintingBinding, SemanticsBinding, RendererBinding, WidgetsBinding {
   _DriverBinding(this._handler, this._silenceErrors, this._enableTextEntryEmulation, this.finders, this.commands);
 
   final DataHandler? _handler;
@@ -51,6 +51,11 @@ class _DriverBinding extends BindingBase with SchedulerBinding, ServicesBinding,
       registerWebServiceExtension(extension.call);
     }
   }
+
+  @override
+  BinaryMessenger createBinaryMessenger() {
+    return TestDefaultBinaryMessenger(super.createBinaryMessenger());
+  }
 }
 
 /// Enables Flutter Driver VM service extension.
@@ -325,11 +330,11 @@ class FlutterDriverExtension with DeserializeFinderFactory, CreateFinderFactory,
       registerTextInput();
     }
 
-    for (final FinderExtension finder in finders) {
+    for(final FinderExtension finder in finders) {
       _finderExtensions[finder.finderType] = finder;
     }
 
-    for (final CommandExtension command in commands) {
+    for(final CommandExtension command in commands) {
       _commandExtensions[command.commandKind] = command;
     }
   }
@@ -413,7 +418,7 @@ class FlutterDriverExtension with DeserializeFinderFactory, CreateFinderFactory,
   @override
   Command deserializeCommand(Map<String, String> params, DeserializeFinderFactory finderFactory) {
     final String? kind = params['command'];
-    if (_commandExtensions.containsKey(kind)) {
+    if(_commandExtensions.containsKey(kind)) {
       return _commandExtensions[kind]!.deserialize(params, finderFactory, this);
     }
 
@@ -429,7 +434,7 @@ class FlutterDriverExtension with DeserializeFinderFactory, CreateFinderFactory,
   @override
   Future<Result> handleCommand(Command command, WidgetController prober, CreateFinderFactory finderFactory) {
     final String kind = command.kind;
-    if (_commandExtensions.containsKey(kind)) {
+    if(_commandExtensions.containsKey(kind)) {
       return _commandExtensions[kind]!.call(command, prober, finderFactory, this);
     }
 

packages/flutter_driver/test/src/real_tests/extension_test.dart

@@ -279,7 +279,7 @@ void main() {
         'waiting for NoPendingPlatformMessages returns until a single method channel call returns', (WidgetTester tester) async {
       const MethodChannel channel = MethodChannel('helloChannel', JSONMethodCodec());
       const MessageCodec<dynamic> jsonMessage = JSONMessageCodec();
-      tester.binding.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
           'helloChannel', (ByteData? message) {
             return Future<ByteData>.delayed(
                 const Duration(milliseconds: 10),
@@ -313,7 +313,7 @@ void main() {
       const MessageCodec<dynamic> jsonMessage = JSONMessageCodec();
       // Configures channel 1
       const MethodChannel channel1 = MethodChannel('helloChannel1', JSONMethodCodec());
-      tester.binding.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
           'helloChannel1', (ByteData? message) {
             return Future<ByteData>.delayed(
                 const Duration(milliseconds: 10),
@@ -322,7 +322,7 @@ void main() {
 
       // Configures channel 2
       const MethodChannel channel2 = MethodChannel('helloChannel2', JSONMethodCodec());
-      tester.binding.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
           'helloChannel2', (ByteData? message) {
             return Future<ByteData>.delayed(
                 const Duration(milliseconds: 20),
@@ -362,7 +362,7 @@ void main() {
       const MessageCodec<dynamic> jsonMessage = JSONMessageCodec();
       // Configures channel 1
       const MethodChannel channel1 = MethodChannel('helloChannel1', JSONMethodCodec());
-      tester.binding.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
           'helloChannel1', (ByteData? message) {
             return Future<ByteData>.delayed(
                 const Duration(milliseconds: 10),
@@ -371,7 +371,7 @@ void main() {
 
       // Configures channel 2
       const MethodChannel channel2 = MethodChannel('helloChannel2', JSONMethodCodec());
-      tester.binding.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
           'helloChannel2', (ByteData? message) {
             return Future<ByteData>.delayed(
                 const Duration(milliseconds: 20),
@@ -413,7 +413,7 @@ void main() {
       const MessageCodec<dynamic> jsonMessage = JSONMessageCodec();
       // Configures channel 1
       const MethodChannel channel1 = MethodChannel('helloChannel1', JSONMethodCodec());
-      tester.binding.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
           'helloChannel1', (ByteData? message) {
             return Future<ByteData>.delayed(
                 const Duration(milliseconds: 20),
@@ -422,7 +422,7 @@ void main() {
 
       // Configures channel 2
       const MethodChannel channel2 = MethodChannel('helloChannel2', JSONMethodCodec());
-      tester.binding.defaultBinaryMessenger.setMockMessageHandler(
+      ServicesBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(
           'helloChannel2', (ByteData? message) {
             return Future<ByteData>.delayed(
                 const Duration(milliseconds: 10),

packages/flutter_test/lib/flutter_test.dart

@@ -61,7 +61,6 @@ export 'src/all_elements.dart';
 export 'src/animation_sheet.dart';
 export 'src/binding.dart';
 export 'src/controller.dart';
-export 'src/deprecated.dart';
 export 'src/event_simulation.dart';
 export 'src/finders.dart';
 export 'src/frame_timing_summarizer.dart';
@@ -74,7 +73,6 @@ export 'src/restoration.dart';
 export 'src/stack_manipulation.dart';
 export 'src/test_async_utils.dart';
 export 'src/test_compat.dart';
-export 'src/test_default_binary_messenger.dart';
 export 'src/test_exception_reporter.dart';
 export 'src/test_pointer.dart';
 export 'src/test_text_input.dart';

packages/flutter_test/lib/src/_binding_io.dart

@@ -13,8 +13,8 @@ import 'package:path/path.dart' as path;
 // ignore: deprecated_member_use
 import 'package:test_api/test_api.dart' as test_package;
 
+
 import 'binding.dart';
-import 'deprecated.dart';
 
 /// Ensure the [WidgetsBinding] is initialized.
 WidgetsBinding ensureInitialized([@visibleForTesting Map<String, String>? environment]) {

packages/flutter_test/lib/src/binding.dart

@@ -15,7 +15,8 @@ import 'package:flutter/services.dart';
 import 'package:flutter/widgets.dart';
 import 'package:flutter_test/flutter_test.dart' show TestWindow;
 import 'package:stack_trace/stack_trace.dart' as stack_trace;
-import 'package:test_api/test_api.dart' as test_package; // ignore: deprecated_member_use
+// ignore: deprecated_member_use
+import 'package:test_api/test_api.dart' as test_package;
 import 'package:vector_math/vector_math_64.dart';
 
 import '_binding_io.dart' if (dart.library.html) '_binding_web.dart' as binding;
@@ -24,7 +25,6 @@ import 'platform.dart';
 import 'restoration.dart';
 import 'stack_manipulation.dart';
 import 'test_async_utils.dart';
-import 'test_default_binary_messenger.dart';
 import 'test_exception_reporter.dart';
 import 'test_text_input.dart';
 
@@ -79,29 +79,74 @@ enum TestBindingEventSource {
 
 const Size _kDefaultTestViewportSize = Size(800.0, 600.0);
 
-/// Overrides the [ServicesBinding]'s binary messenger logic to use
+/// A [BinaryMessenger] subclass that is used as the default binary messenger
-/// [TestDefaultBinaryMessenger].
+/// under testing environment.
 ///
-/// Test bindings that are used by tests that mock message handlers for plugins
+/// It tracks status of data sent across the Flutter platform barrier, which is
-/// should mix in this binding to enable the use of the
+/// useful for testing frameworks to monitor and synchronize against the
-/// [TestDefaultBinaryMessenger] APIs.
+/// platform messages.
-mixin TestDefaultBinaryMessengerBinding on BindingBase, ServicesBinding {
+class TestDefaultBinaryMessenger extends BinaryMessenger {
+  /// Creates a [TestDefaultBinaryMessenger] instance.
+  ///
+  /// The [delegate] instance must not be null.
+  TestDefaultBinaryMessenger(this.delegate): assert(delegate != null);
+
+  /// The delegate [BinaryMessenger].
+  final BinaryMessenger delegate;
+
+  final List<Future<ByteData?>> _pendingMessages = <Future<ByteData?>>[];
+
+  /// The number of incomplete/pending calls sent to the platform channels.
+  int get pendingMessageCount => _pendingMessages.length;
+
   @override
-  void initInstances() {
+  Future<ByteData?>? send(String channel, ByteData? message) {
-    super.initInstances();
+    final Future<ByteData?>? resultFuture = delegate.send(channel, message);
-    _instance = this;
+    if (resultFuture != null) {
+      _pendingMessages.add(resultFuture);
+      resultFuture
+        .catchError((Object error) { /* errors are the responsibility of the caller */ })
+        .whenComplete(() => _pendingMessages.remove(resultFuture));
+    }
+    return resultFuture;
   }
 
-  /// The current [TestDefaultBinaryMessengerBinding], if one has been created.
+  /// Returns a Future that completes after all the platform calls are finished.
-  static TestDefaultBinaryMessengerBinding? get instance => _instance;
+  ///
-  static TestDefaultBinaryMessengerBinding? _instance;
+  /// If a new platform message is sent after this method is called, this new
+  /// message is not tracked. Use with [pendingMessageCount] to guarantee no
+  /// pending message calls.
+  Future<void> get platformMessagesFinished {
+    return Future.wait<void>(_pendingMessages);
+  }
 
   @override
-  TestDefaultBinaryMessenger get defaultBinaryMessenger => super.defaultBinaryMessenger as TestDefaultBinaryMessenger;
+  Future<void> handlePlatformMessage(
+      String channel,
+      ByteData? data,
+      ui.PlatformMessageResponseCallback? callback,
+  ) {
+    return delegate.handlePlatformMessage(channel, data, callback);
+  }
 
   @override
-  TestDefaultBinaryMessenger createBinaryMessenger() {
+  void setMessageHandler(String channel, MessageHandler? handler) {
-    return TestDefaultBinaryMessenger(super.createBinaryMessenger());
+    delegate.setMessageHandler(channel, handler);
+  }
+
+  @override
+  bool checkMessageHandler(String channel, MessageHandler? handler) {
+    return delegate.checkMessageHandler(channel, handler);
+  }
+
+  @override
+  void setMockMessageHandler(String channel, MessageHandler? handler) {
+    delegate.setMockMessageHandler(channel, handler);
+  }
+
+  @override
+  bool checkMockMessageHandler(String channel, MessageHandler? handler) {
+    return delegate.checkMockMessageHandler(channel, handler);
   }
 }
 
@@ -126,8 +171,7 @@ abstract class TestWidgetsFlutterBinding extends BindingBase
        SemanticsBinding,
        RendererBinding,
        PaintingBinding,
-       WidgetsBinding,
+       WidgetsBinding {
-       TestDefaultBinaryMessengerBinding {
 
   /// Constructor for [TestWidgetsFlutterBinding].
   ///
@@ -304,6 +348,11 @@ abstract class TestWidgetsFlutterBinding extends BindingBase
     // doesn't get generated for tests.
   }
 
+  @override
+  BinaryMessenger createBinaryMessenger() {
+    return TestDefaultBinaryMessenger(super.createBinaryMessenger());
+  }
+
   /// Whether there is currently a test executing.
   bool get inTest;
 

packages/flutter_test/lib/src/deprecated.dart

@@ -1,109 +0,0 @@
-// Copyright 2014 The Flutter 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 'package:flutter/services.dart';
-
-import 'binding.dart';
-
-// TODO(ianh): Once https://github.com/dart-lang/dartdoc/issues/2033 is fixed, update the hyperlinks marked HYPERLINK below.
-// TODO(ianh): Once cocoon and other customer_tests are migrated, deprecate these transitional APIs
-
-/// Shim to support the obsolete [setMockMessageHandler] and
-/// [checkMockMessageHandler] methods on [BinaryMessenger] in tests.
-///
-/// The implementations defer to [TestDefaultBinaryMessengerBinding.defaultBinaryMessenger].
-///
-/// Rather than calling [setMockMessageHandler] on the
-/// `ServicesBinding.defaultBinaryMessenger`, use
-/// `tester.binding.defaultBinaryMessenger.setMockMessageHandler` directly. This
-/// more accurately represents the actual method invocation.
-extension TestBinaryMessengerExtension on BinaryMessenger {
-  /// Shim for `TestDefaultBinaryMessenger.setMockMessageHandler`.
-  // HYPERLINK ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-  // TODO(ianh): deprecate this method: @NotYetDeprecated(
-  //   'Use tester.binding.defaultBinaryMessenger.setMockMessageHandler or '
-  //   'TestDefaultBinaryMessenger.instance.defaultBinaryMessenger.setMockMessageHandler instead. '
-  //   'This feature was deprecated after v2.1.0-10.0.pre.'
-  // )
-  void setMockMessageHandler(String channel, MessageHandler? handler) {
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMessageHandler(channel, handler);
-  }
-
-  /// Shim for `TestDefaultBinaryMessenger.checkMockMessageHandler`.
-  // HYPERLINK ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-  // TODO(ianh): deprecate this method: @NotYetDeprecated(
-  //   'Use tester.binding.defaultBinaryMessenger.checkMockMessageHandler or '
-  //   'TestDefaultBinaryMessenger.instance.defaultBinaryMessenger.checkMockMessageHandler instead.'
-  //   'This feature was deprecated after v2.1.0-10.0.pre.'
-  // )
-  bool checkMockMessageHandler(String channel, Object? handler) {
-    return TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.checkMockMessageHandler(channel, handler);
-  }
-}
-
-/// Shim to support the obsolete [setMockMessageHandler] and
-/// [checkMockMessageHandler] methods on [BasicMessageChannel] in tests.
-///
-/// The implementations defer to [TestDefaultBinaryMessengerBinding.defaultBinaryMessenger].
-///
-/// Rather than calling [setMockMessageHandler] on the message channel, use
-/// `tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler`
-/// directly. This more accurately represents the actual method invocation.
-extension TestBasicMessageChannelExtension<T> on BasicMessageChannel<T> {
-  /// Shim for `TestDefaultBinaryMessenger.setMockDecodedMessageHandler`.
-  // HYPERLINK ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-  // TODO(ianh): deprecate this method: @NotYetDeprecated(
-  //   'Use tester.binding.defaultBinaryMessenger.setMockDecodedMessageHandler or '
-  //   'TestDefaultBinaryMessenger.instance.defaultBinaryMessenger.setMockDecodedMessageHandler instead. '
-  //   'This feature was deprecated after v2.1.0-10.0.pre.'
-  // )
-  void setMockMessageHandler(Future<T> Function(T? message)? handler) {
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockDecodedMessageHandler<T>(this, handler);
-  }
-
-  /// Shim for `TestDefaultBinaryMessenger.checkMockMessageHandler`.
-  // HYPERLINK ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-  // TODO(ianh): deprecate this method: @NotYetDeprecated(
-  //   'Use tester.binding.defaultBinaryMessenger.checkMockMessageHandler or '
-  //   'TestDefaultBinaryMessenger.instance.defaultBinaryMessenger.checkMockMessageHandler instead. '
-  //   'For the first argument, pass channel.name. '
-  //   'This feature was deprecated after v2.1.0-10.0.pre.'
-  // )
-  bool checkMockMessageHandler(Object? handler) {
-    return TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.checkMockMessageHandler(name, handler);
-  }
-}
-
-/// Shim to support the obsolete [setMockMethodCallHandler] and
-/// [checkMockMethodCallHandler] methods on [MethodChannel] in tests.
-///
-/// The implementations defer to [TestDefaultBinaryMessengerBinding.defaultBinaryMessenger].
-///
-/// Rather than calling [setMockMethodCallHandler] on the method channel, use
-/// `tester.binding.defaultBinaryMessenger.setMockMethodCallHandler` directly.
-/// This more accurately represents the actual method invocation.
-extension TestMethodChannelExtension on MethodChannel {
-  /// Shim for `TestDefaultBinaryMessenger.setMockMethodCallHandler`.
-  // HYPERLINK ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-  // TODO(ianh): deprecate this method: @NotYetDeprecated(
-  //   'Use tester.binding.defaultBinaryMessenger.setMockMethodCallHandler or '
-  //   'TestDefaultBinaryMessenger.instance.defaultBinaryMessenger.setMockMethodCallHandler instead. '
-  //   'This feature was deprecated after v2.1.0-10.0.pre.'
-  // )
-  void setMockMethodCallHandler(Future<dynamic>? Function(MethodCall call)? handler) {
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.setMockMethodCallHandler(this, handler);
-  }
-
-  /// Shim for `TestDefaultBinaryMessenger.checkMockMessageHandler`.
-  // HYPERLINK ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-  // TODO(ianh): deprecate this method: @NotYetDeprecated(
-  //   'Use tester.binding.defaultBinaryMessenger.checkMockMessageHandler or '
-  //   'TestDefaultBinaryMessenger.instance.defaultBinaryMessenger.checkMockMessageHandler instead. '
-  //   'For the first argument, pass channel.name. '
-  //   'This feature was deprecated after v2.1.0-10.0.pre.'
-  // )
-  bool checkMockMethodCallHandler(Object? handler) {
-    return TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.checkMockMessageHandler(name, handler);
-  }
-}

packages/flutter_test/lib/src/event_simulation.dart

@@ -2,13 +2,10 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-import 'dart:async';
 import 'dart:io';
 
 import 'package:flutter/foundation.dart' show kIsWeb;
 import 'package:flutter/services.dart';
-
-import 'binding.dart';
 import 'test_async_utils.dart';
 
 // TODO(gspencergoog): Replace this with more robust key simulation code once
@@ -640,20 +637,21 @@ class KeyEventSimulator {
       assert(_osIsSupported(platform!), 'Platform $platform not supported for key simulation');
 
       final Map<String, dynamic> data = getKeyData(key, platform: platform!, isDown: true, physicalKey: physicalKey);
-      final Completer<bool> result = Completer<bool>();
+      bool result = false;
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
         (ByteData? data) {
           if (data == null) {
-            result.complete(false);
             return;
           }
           final Map<String, dynamic> decoded = SystemChannels.keyEvent.codec.decodeMessage(data) as Map<String, dynamic>;
-          result.complete(decoded['handled'] as bool);
+          if (decoded['handled'] as bool) {
+            result = true;
+          }
         }
       );
-      return result.future;
+      return result;
     });
   }
 
@@ -679,7 +677,7 @@ class KeyEventSimulator {
 
       final Map<String, dynamic> data = getKeyData(key, platform: platform!, isDown: false, physicalKey: physicalKey);
       bool result = false;
-      await TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      await ServicesBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
         SystemChannels.keyEvent.name,
         SystemChannels.keyEvent.codec.encodeMessage(data),
         (ByteData? data) {

packages/flutter_test/lib/src/test_default_binary_messenger.dart

@@ -1,306 +0,0 @@
-// Copyright 2014 The Flutter 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:async';
-import 'dart:ui' as ui;
-
-import 'package:fake_async/fake_async.dart';
-import 'package:flutter/services.dart';
-
-/// A [BinaryMessenger] subclass that is used as the default binary messenger
-/// under testing environment.
-///
-/// It tracks status of data sent across the Flutter platform barrier, which is
-/// useful for testing frameworks to monitor and synchronize against the
-/// platform messages.
-///
-/// ## Messages from the framework to the platform
-///
-/// Messages are sent from the framework to the platform via the
-/// [send] method.
-///
-/// To intercept a message sent from the framework to the platform,
-/// consider using [setMockMessageHandler],
-/// [setMockDecodedMessageHandler], and [setMockMethodCallHandler]
-/// (see also [checkMockMessageHandler]).
-///
-/// To wait for all pending framework-to-platform messages, the
-/// [platformMessagesFinished] getter provides an appropriate
-/// [Future]. The [pendingMessageCount] getter returns the current
-/// number of outstanding messages.
-///
-/// ## Messages from the platform to the framework
-///
-/// The platform sends messages via the [ChannelBuffers] API. Mock
-/// messages can be sent to the framework using
-/// [handlePlatformMessage].
-///
-/// Listeners for these messages are configured using [setMessageHandler].
-class TestDefaultBinaryMessenger extends BinaryMessenger {
-  /// Creates a [TestDefaultBinaryMessenger] instance.
-  ///
-  /// The [delegate] instance must not be null.
-  TestDefaultBinaryMessenger(this.delegate): assert(delegate != null);
-
-  /// The delegate [BinaryMessenger].
-  final BinaryMessenger delegate;
-
-  // The handlers for messages from the engine (including fake
-  // messages sent by handlePlatformMessage).
-  final Map<String, MessageHandler> _inboundHandlers = <String, MessageHandler>{};
-
-  /// Send a mock message to the framework as if it came from the platform.
-  ///
-  /// If a listener has been set using [setMessageHandler], that listener is
-  /// invoked to handle the message, and this method returns a future that
-  /// completes with that handler's result.
-  ///
-  /// {@template flutter.flutter_test.TestDefaultBinaryMessenger.handlePlatformMessage.asyncHandlers}
-  /// It is strongly recommended that all handlers used with this API be
-  /// synchronous (not requiring any microtasks to complete), because
-  /// [testWidgets] tests run in a [FakeAsync] zone in which microtasks do not
-  /// progress except when time is explicitly advanced (e.g. with
-  /// [WidgetTester.pump]), which means that `await`ing a [Future] will result
-  /// in the test hanging.
-  /// {@endtemplate}
-  ///
-  /// If no listener is configured, this method returns right away with null.
-  ///
-  /// The `callback` argument, if non-null, will be called just before this
-  /// method's future completes, either with the result of the listener
-  /// registered with [setMessageHandler], or with null if no listener has
-  /// been registered.
-  ///
-  /// Messages can also be sent via [ChannelBuffers.push] (see
-  /// [ServicesBinding.channelBuffers]); the effect is the same, though that API
-  /// will not wait for a response.
-  // TODO(ianh): When the superclass `handlePlatformMessage` is removed,
-  // remove this @override (but leave the method).
-  @override
-  Future<ByteData?> handlePlatformMessage(
-    String channel,
-    ByteData? data,
-    ui.PlatformMessageResponseCallback? callback,
-  ) {
-    Future<ByteData?>? result;
-    if (_inboundHandlers.containsKey(channel))
-      result = _inboundHandlers[channel]!(data);
-    result ??= Future<ByteData?>.value(null);
-    if (callback != null)
-      result = result.then((ByteData? result) { callback(result); return result; });
-    return result;
-  }
-
-  @override
-  void setMessageHandler(String channel, MessageHandler? handler) {
-    if (handler == null) {
-      _inboundHandlers.remove(channel);
-      delegate.setMessageHandler(channel, null);
-    } else {
-      _inboundHandlers[channel] = handler; // used to handle fake messages sent via handlePlatformMessage
-      delegate.setMessageHandler(channel, handler); // used to handle real messages from the engine
-    }
-  }
-
-  final List<Future<ByteData?>> _pendingMessages = <Future<ByteData?>>[];
-
-  /// The number of incomplete/pending calls sent to the platform channels.
-  int get pendingMessageCount => _pendingMessages.length;
-
-  // Handlers that intercept and respond to outgoing messages,
-  // pretending to be the platform.
-  final Map<String, MessageHandler> _outboundHandlers = <String, MessageHandler>{};
-
-  // The outbound callbacks that were actually registered, so that we
-  // can implement the [checkMockMessageHandler] method.
-  final Map<String, Object> _outboundHandlerIdentities = <String, Object>{};
-
-  @override
-  Future<ByteData?>? send(String channel, ByteData? message) {
-    final Future<ByteData?>? resultFuture;
-    final MessageHandler? handler = _outboundHandlers[channel];
-    if (handler != null) {
-      resultFuture = handler(message);
-    } else {
-      resultFuture = delegate.send(channel, message);
-    }
-    if (resultFuture != null) {
-      _pendingMessages.add(resultFuture);
-      resultFuture
-        .catchError((Object error) { /* errors are the responsibility of the caller */ })
-        .whenComplete(() => _pendingMessages.remove(resultFuture));
-    }
-    return resultFuture;
-  }
-
-  /// Returns a Future that completes after all the platform calls are finished.
-  ///
-  /// If a new platform message is sent after this method is called, this new
-  /// message is not tracked. Use with [pendingMessageCount] to guarantee no
-  /// pending message calls.
-  Future<void> get platformMessagesFinished {
-    return Future.wait<void>(_pendingMessages);
-  }
-
-  /// Set a callback for intercepting messages sent to the platform on
-  /// the given channel, without decoding them.
-  ///
-  /// Intercepted messages are not forwarded to the platform.
-  ///
-  /// The given callback will replace the currently registered
-  /// callback for that channel, if any. To stop intercepting messages
-  /// at all, pass null as the handler.
-  ///
-  /// The handler's return value, if non-null, is used as a response,
-  /// unencoded.
-  ///
-  /// {@macro flutter.flutter_test.TestDefaultBinaryMessenger.handlePlatformMessage.asyncHandlers}
-  ///
-  /// The `identity` argument, if non-null, is used to identify the
-  /// callback when checked by [checkMockMessageHandler]. If null, the
-  /// `handler` is used instead. (This allows closures to be passed as
-  /// the `handler` with an alias used as the `identity` so that a
-  /// reference to the closure need not be used. In practice, this is
-  /// used by [setMockDecodedMessageHandler] and
-  /// [setMockMethodCallHandler] to allow [checkMockMessageHandler] to
-  /// recognize the closures that were passed to those methods even
-  /// though those methods wrap those closures when passing them to
-  /// this method.)
-  ///
-  /// Registered callbacks are cleared after each test.
-  ///
-  /// See also:
-  ///
-  ///  * [checkMockMessageHandler], which can verify if a handler is still
-  ///    registered, which is useful in tests to ensure that no unexpected
-  ///    handlers are being registered.
-  ///
-  ///  * [setMockDecodedMessageHandler], which wraps this method but
-  ///    decodes the messages using a [MessageCodec].
-  ///
-  ///  * [setMockMethodCallHandler], which wraps this method but decodes
-  ///    the messages using a [MethodCodec].
-  void setMockMessageHandler(String channel, MessageHandler? handler, [ Object? identity ]) {
-    if (handler == null) {
-      _outboundHandlers.remove(channel);
-      _outboundHandlerIdentities.remove(channel);
-    } else {
-      identity ??= handler;
-      _outboundHandlers[channel] = handler;
-      _outboundHandlerIdentities[channel] = identity;
-    }
-  }
-
-  /// Set a callback for intercepting messages sent to the platform on
-  /// the given channel.
-  ///
-  /// Intercepted messages are not forwarded to the platform.
-  ///
-  /// The given callback will replace the currently registered
-  /// callback for that channel, if any. To stop intercepting messages
-  /// at all, pass null as the handler.
-  ///
-  /// Messages are decoded using the codec of the channel.
-  ///
-  /// The handler's return value, if non-null, is used as a response,
-  /// after encoding it using the channel's codec.
-  ///
-  /// {@macro flutter.flutter_test.TestDefaultBinaryMessenger.handlePlatformMessage.asyncHandlers}
-  ///
-  /// Registered callbacks are cleared after each test.
-  ///
-  /// See also:
-  ///
-  ///  * [checkMockMessageHandler], which can verify if a handler is still
-  ///    registered, which is useful in tests to ensure that no unexpected
-  ///    handlers are being registered.
-  ///
-  ///  * [setMockMessageHandler], which is similar but provides raw
-  ///    access to the underlying bytes.
-  ///
-  ///  * [setMockMethodCallHandler], which is similar but decodes
-  ///    the messages using a [MethodCodec].
-  void setMockDecodedMessageHandler<T>(BasicMessageChannel<T> channel, Future<T> Function(T? message)? handler) {
-    if (handler == null) {
-      setMockMessageHandler(channel.name, null);
-      return;
-    }
-    setMockMessageHandler(channel.name, (ByteData? message) async {
-      return channel.codec.encodeMessage(await handler(channel.codec.decodeMessage(message)));
-    }, handler);
-  }
-
-  /// Set a callback for intercepting method calls sent to the
-  /// platform on the given channel.
-  ///
-  /// Intercepted method calls are not forwarded to the platform.
-  ///
-  /// The given callback will replace the currently registered
-  /// callback for that channel, if any. To stop intercepting messages
-  /// at all, pass null as the handler.
-  ///
-  /// Methods are decoded using the codec of the channel.
-  ///
-  /// The handler's return value, if non-null, is used as a response,
-  /// after re-encoding it using the channel's codec.
-  ///
-  /// To send an error, throw a [PlatformException] in the handler.
-  /// Other exceptions are not caught.
-  ///
-  /// {@macro flutter.flutter_test.TestDefaultBinaryMessenger.handlePlatformMessage.asyncHandlers}
-  ///
-  /// Registered callbacks are cleared after each test.
-  ///
-  /// See also:
-  ///
-  ///  * [checkMockMessageHandler], which can verify if a handler is still
-  ///    registered, which is useful in tests to ensure that no unexpected
-  ///    handlers are being registered.
-  ///
-  ///  * [setMockMessageHandler], which is similar but provides raw
-  ///    access to the underlying bytes.
-  ///
-  ///  * [setMockDecodedMessageHandler], which is similar but decodes
-  ///    the messages using a [MessageCodec].
-  void setMockMethodCallHandler(MethodChannel channel, Future<Object?>? Function(MethodCall message)? handler) {
-    if (handler == null) {
-      setMockMessageHandler(channel.name, null);
-      return;
-    }
-    setMockMessageHandler(channel.name, (ByteData? message) async {
-      final MethodCall call = channel.codec.decodeMethodCall(message);
-      try {
-        return channel.codec.encodeSuccessEnvelope(await handler(call));
-      } on PlatformException catch (error) {
-        return channel.codec.encodeErrorEnvelope(
-          code: error.code,
-          message: error.message,
-          details: error.details,
-        );
-      } on MissingPluginException {
-        return null;
-      } catch (error) {
-        return channel.codec.encodeErrorEnvelope(code: 'error', message: '$error', details: null);
-      }
-    }, handler);
-  }
-
-  /// Returns true if the `handler` argument matches the `handler`
-  /// previously passed to [setMockMessageHandler],
-  /// [setMockDecodedMessageHandler], or [setMockMethodCallHandler].
-  ///
-  /// Specifically, it compares the argument provided to the `identity`
-  /// argument provided to [setMockMessageHandler], defaulting to the
-  /// `handler` argument passed to that method is `identity` was null.
-  ///
-  /// This method is useful for tests or test harnesses that want to assert the
-  /// mock handler for the specified channel has not been altered by a previous
-  /// test.
-  ///
-  /// Passing null for the `handler` returns true if the handler for the
-  /// `channel` is not set.
-  ///
-  /// Registered callbacks are cleared after each test.
-  bool checkMockMessageHandler(String channel, Object? handler) => _outboundHandlerIdentities[channel] == handler;
-}

packages/flutter_test/lib/src/test_text_input.dart

@@ -8,10 +8,6 @@ import 'package:flutter/foundation.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_test/flutter_test.dart';
 
-import 'binding.dart' show TestDefaultBinaryMessengerBinding;
-import 'deprecated.dart';
-import 'test_async_utils.dart';
-
 export 'package:flutter/services.dart' show TextEditingValue, TextInputAction;
 
 /// A testing stub for the system's onscreen keyboard.
@@ -49,6 +45,9 @@ class TestTextInput {
   /// first be requested, e.g. using [WidgetTester.showKeyboard].
   final VoidCallback? onCleared;
 
+  /// The messenger which sends the bytes for this channel, not null.
+  BinaryMessenger get _binaryMessenger => ServicesBinding.instance!.defaultBinaryMessenger;
+
   /// Log for method calls.
   ///
   /// For all registered channels, handled calls are added to the list. Can
@@ -154,25 +153,16 @@ class TestTextInput {
     _isVisible = false;
   }
 
-  /// Simulates the user changing the text of the focused text field, and resets
+  /// Simulates the user typing the given text.
-  /// the selection.
   ///
   /// Calling this method replaces the content of the connected input field with
   /// `text`, and places the caret at the end of the text.
   ///
-  /// To update the UI under test after this method is invoked, use
-  /// [WidgetTester.pump].
-  ///
   /// This can be called even if the [TestTextInput] has not been [register]ed.
   ///
   /// If this is used to inject text when there is a real IME connection, for
   /// example when using the [integration_test] library, there is a risk that
   /// the real IME will become confused as to the current state of input.
-  ///
-  /// See also:
-  ///
-  ///  * [updateEditingValue], which takes a [TextEditingValue] so that one can
-  ///    also change the selection.
   void enterText(String text) {
     updateEditingValue(TextEditingValue(
       text: text,
@@ -182,21 +172,13 @@ class TestTextInput {
 
   /// Simulates the user changing the [TextEditingValue] to the given value.
   ///
-  /// To update the UI under test after this method is invoked, use
-  /// [WidgetTester.pump].
-  ///
   /// This can be called even if the [TestTextInput] has not been [register]ed.
   ///
   /// If this is used to inject text when there is a real IME connection, for
   /// example when using the [integration_test] library, there is a risk that
   /// the real IME will become confused as to the current state of input.
-  ///
-  /// See also:
-  ///
-  ///  * [enterText], which is similar but takes only a String and resets the
-  ///    selection.
   void updateEditingValue(TextEditingValue value) {
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+    _binaryMessenger.handlePlatformMessage(
       SystemChannels.textInput.name,
       SystemChannels.textInput.codec.encodeMethodCall(
         MethodCall(
@@ -204,7 +186,7 @@ class TestTextInput {
           <dynamic>[_client ?? -1, value.toJSON()],
         ),
       ),
-      (ByteData? data) { /* ignored */ },
+      (ByteData? data) { /* response from framework is discarded */ },
     );
   }
 
@@ -220,7 +202,7 @@ class TestTextInput {
   Future<void> receiveAction(TextInputAction action) async {
     return TestAsyncUtils.guard(() {
       final Completer<void> completer = Completer<void>();
-      TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+      _binaryMessenger.handlePlatformMessage(
         SystemChannels.textInput.name,
         SystemChannels.textInput.codec.encodeMethodCall(
           MethodCall(
@@ -234,7 +216,8 @@ class TestTextInput {
             // Decoding throws a PlatformException if the data represents an
             // error, and that's all we care about here.
             SystemChannels.textInput.codec.decodeEnvelope(data!);
-            // If we reach here then no error was found. Complete without issue.
+
+            // No error was found. Complete without issue.
             completer.complete();
           } catch (error) {
             // An exception occurred as a result of receiveAction()'ing. Report
@@ -243,6 +226,7 @@ class TestTextInput {
           }
         },
       );
+
       return completer.future;
     });
   }
@@ -260,7 +244,7 @@ class TestTextInput {
   /// example when using the [integration_test] library, there is a risk that
   /// the real IME will become confused as to the current state of input.
   void closeConnection() {
-    TestDefaultBinaryMessengerBinding.instance!.defaultBinaryMessenger.handlePlatformMessage(
+    _binaryMessenger.handlePlatformMessage(
       SystemChannels.textInput.name,
       SystemChannels.textInput.codec.encodeMethodCall(
         MethodCall(

packages/flutter_test/lib/src/widget_tester.dart

@@ -129,7 +129,7 @@ void testWidgets(
   dynamic tags,
 }) {
   assert(variant != null);
-  assert(variant.values.isNotEmpty, 'There must be at least one value to test in the testing variant.');
+  assert(variant.values.isNotEmpty, 'There must be at least on value to test in the testing variant');
   final TestWidgetsFlutterBinding binding = TestWidgetsFlutterBinding.ensureInitialized() as TestWidgetsFlutterBinding;
   final WidgetTester tester = WidgetTester._(binding);
   for (final dynamic value in variant.values) {
@@ -147,7 +147,7 @@ void testWidgets(
         test_package.addTearDown(binding.postTest);
         return binding.runTest(
           () async {
-            binding.reset(); // TODO(ianh): the binding should just do this itself in _runTest
+            binding.reset();
             debugResetSemanticsIdCounter();
             Object? memento;
             try {
@@ -917,12 +917,10 @@ class WidgetTester extends WidgetController implements HitTestDispatcher, Ticker
   /// Acts as if the application went idle.
   ///
   /// Runs all remaining microtasks, including those scheduled as a result of
-  /// running them, until there are no more microtasks scheduled. Then, runs any
+  /// running them, until there are no more microtasks scheduled.
-  /// previously scheduled timers with zero time, and completes the returned future.
   ///
-  /// May result in an infinite loop or run out of memory if microtasks continue
+  /// Does not run timers. May result in an infinite loop or run out of memory
-  /// to recursively schedule new microtasks. Will not run any timers scheduled
+  /// if microtasks continue to recursively schedule new microtasks.
-  /// after this method was invoked, even if they are zero-time timers.
   Future<void> idle() {
     return TestAsyncUtils.guard<void>(() => binding.idle());
   }

packages/flutter_test/lib/src/window.dart

@@ -379,16 +379,8 @@ class TestWindow implements ui.SingletonFlutterWindow {
     platformDispatcher.sendPlatformMessage(name, data, callback);
   }
 
-  @Deprecated(
-    'Instead of calling this callback, use ServicesBinding.instance.channelBuffers.push. '
-    'This feature was deprecated after v2.1.0-10.0.pre.'
-  )
   @override
   ui.PlatformMessageCallback? get onPlatformMessage => platformDispatcher.onPlatformMessage;
-  @Deprecated(
-    'Instead of setting this callback, use ServicesBinding.instance.defaultBinaryMessenger.setMessageHandler. '
-    'This feature was deprecated after v2.1.0-10.0.pre.'
-  )
   @override
   set onPlatformMessage(ui.PlatformMessageCallback? callback) {
     platformDispatcher.onPlatformMessage = callback;

packages/flutter_test/test/test_default_binary_messenger_test.dart

@@ -20,6 +20,12 @@ class TestDelegate extends BinaryMessenger {
   Future<void> handlePlatformMessage(String channel, ByteData? data, ui.PlatformMessageResponseCallback? callback) => throw UnimplementedError();
   @override
   void setMessageHandler(String channel, MessageHandler? handler) => throw UnimplementedError();
+  @override
+  bool checkMessageHandler(String channel, MessageHandler? handler) => throw UnimplementedError();
+  @override
+  void setMockMessageHandler(String channel, MessageHandler? handler) => throw UnimplementedError();
+  @override
+  bool checkMockMessageHandler(String channel, MessageHandler? handler) => throw UnimplementedError();
 }
 
 void main() {

packages/flutter_web_plugins/lib/src/plugin_registry.dart

@@ -61,7 +61,7 @@ class Registrar extends BinaryMessenger {
   /// the [dart:ui] library. That function is only available when
   /// compiling for the web.
   void registerMessageHandler() {
-    // The `ui.webOnlySetPluginHandler` function below is only defined in the Web dart:ui.
+    // The function below is only defined in the Web dart:ui.
     // ignore: undefined_function
     ui.webOnlySetPluginHandler(handleFrameworkMessage);
   }
@@ -141,7 +141,7 @@ class Registrar extends BinaryMessenger {
   @override
   Future<ByteData?> send(String channel, ByteData? message) {
     final Completer<ByteData?> completer = Completer<ByteData?>();
-    ui.channelBuffers.push(channel, message, (ByteData? reply) {
+    ui.window.onPlatformMessage!(channel, message, (ByteData? reply) {
       try {
         completer.complete(reply);
       } catch (exception, stack) {
@@ -163,6 +163,26 @@ class Registrar extends BinaryMessenger {
     else
       _handlers[channel] = handler;
   }
+
+  @override
+  bool checkMessageHandler(String channel, MessageHandler? handler) => _handlers[channel] == handler;
+
+  @override
+  void setMockMessageHandler(
+    String channel,
+    MessageHandler? handler,
+  ) {
+    throw FlutterError(
+      'Setting mock handlers is not supported on the platform side.',
+    );
+  }
+
+  @override
+  bool checkMockMessageHandler(String channel, MessageHandler? handler) {
+    throw FlutterError(
+      'Setting mock handlers is not supported on the platform side.',
+    );
+  }
 }
 
 /// This class was previously separate from [Registrar] but was merged into it

packages/flutter_web_plugins/test/plugin_registry_test.dart

@@ -71,5 +71,12 @@ void main() {
       ServicesBinding.instance!.defaultBinaryMessenger
           .setMessageHandler('test_send', null);
     });
+
+    test('throws when trying to set a mock handler', () {
+      expect(
+          () => pluginBinaryMessenger.setMockMessageHandler(
+              'test', (ByteData? data) async => ByteData(0)),
+          throwsFlutterError);
+    });
   });
 }