Reland "Remove all service extensions from release mode (#23038)" (#23291)

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

@@ -93,9 +93,7 @@ abstract class BindingBase {
   /// Implementations of this method must call their superclass
   /// implementation.
   ///
-  /// Service extensions are only exposed when the observatory is
+  /// {@macro flutter.foundation.bindingBase.registerServiceExtension}
-  /// included in the build, which should only happen in checked mode
-  /// and in profile mode.
   ///
   /// See also:
   ///
@@ -104,18 +102,23 @@ abstract class BindingBase {
   @mustCallSuper
   void initServiceExtensions() {
     assert(!_debugServiceExtensionsRegistered);
+
+    assert(() {
       registerSignalServiceExtension(
         name: 'reassemble',
         callback: reassembleApplication,
       );
+      return true;
+    }());
+
+    const bool isReleaseMode = bool.fromEnvironment('dart.vm.product');
+    if (!isReleaseMode) {
       registerSignalServiceExtension(
         name: 'exit',
         callback: _exitApplication,
       );
-    registerSignalServiceExtension(
+    }
-      name: 'frameworkPresent',
+
-      callback: () => Future<void>.value(),
-    );
     assert(() {
       registerServiceExtension(
         name: 'platformOverride',
@@ -239,6 +242,8 @@ abstract class BindingBase {
   /// no value.
   ///
   /// Calls the `callback` callback when the service extension is called.
+  ///
+  /// {@macro flutter.foundation.bindingBase.registerServiceExtension}
   @protected
   void registerSignalServiceExtension({
     @required String name,
@@ -267,6 +272,8 @@ abstract class BindingBase {
   ///
   /// Calls the `setter` callback with the new value when the
   /// service extension method is called with a new value.
+  ///
+  /// {@macro flutter.foundation.bindingBase.registerServiceExtension}
   @protected
   void registerBoolServiceExtension({
     @required String name,
@@ -297,6 +304,8 @@ abstract class BindingBase {
   ///
   /// Calls the `setter` callback with the new value when the
   /// service extension method is called with a new value.
+  ///
+  /// {@macro flutter.foundation.bindingBase.registerServiceExtension}
   @protected
   void registerNumericServiceExtension({
     @required String name,
@@ -326,6 +335,8 @@ abstract class BindingBase {
   ///
   /// Calls the `setter` callback with the new value when the
   /// service extension method is called with a new value.
+  ///
+  /// {@macro flutter.foundation.bindingBase.registerServiceExtension}
   @protected
   void registerStringServiceExtension({
     @required String name,
@@ -345,16 +356,51 @@ abstract class BindingBase {
     );
   }
 
-  /// Registers a service extension method with the given name (full
+  /// Registers a service extension method with the given name (full name
-  /// name "ext.flutter.name"). The given callback is called when the
+  /// "ext.flutter.name").
-  /// extension method is called. The callback must return a [Future]
+  ///
-  /// that either eventually completes to a return value in the form
+  /// The given callback is called when the extension method is called. The
-  /// of a name/value map where the values can all be converted to
+  /// callback must return a [Future] that either eventually completes to a
-  /// JSON using `json.encode()` (see [JsonEncoder]), or fails. In case of failure, the
+  /// return value in the form of a name/value map where the values can all be
-  /// failure is reported to the remote caller and is dumped to the
+  /// converted to JSON using `json.encode()` (see [JsonEncoder]), or fails. In
-  /// logs.
+  /// case of failure, the failure is reported to the remote caller and is
+  /// dumped to the logs.
   ///
   /// The returned map will be mutated.
+  ///
+  /// {@template flutter.foundation.bindingBase.registerServiceExtension}
+  /// A registered service extension can only be activated if the vm-service
+  /// is included in the build, which only happens in debug and profile mode.
+  /// Although a service extension cannot be used in release mode its code may
+  /// still be included in the Dart snapshot and blow up binary size if it is
+  /// not wrapped in a guard that allows the tree shaker to remove it (see
+  /// sample code below).
+  ///
+  /// ## Sample Code
+  ///
+  /// The following code registers a service extension that is only included in
+  /// debug builds:
+  ///
+  /// ```dart
+  /// assert(() {
+  ///   // Register your service extension here.
+  ///   return true;
+  /// }());
+  ///
+  /// ```
+  ///
+  /// A service extension registered with the following code snippet is
+  /// available in debug and profile mode:
+  ///
+  /// ```dart
+  /// if (!const bool.fromEnvironment('dart.vm.product')) {
+  //   // Register your service extension here.
+  // }
+  /// ```
+  ///
+  /// Both guards ensure that Dart's tree shaker can remove the code for the
+  /// service extension in release builds.
+  /// {@endTemplate}
   @protected
   void registerServiceExtension({
     @required String name,

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

@@ -51,7 +51,7 @@ mixin RendererBinding on BindingBase, ServicesBinding, SchedulerBinding, Semanti
     super.initServiceExtensions();
 
     assert(() {
-      // these service extensions only work in checked mode
+      // these service extensions only work in debug mode
       registerBoolServiceExtension(
         name: 'debugPaint',
         getter: () async => debugPaintSizeEnabled,
@@ -60,7 +60,7 @@ mixin RendererBinding on BindingBase, ServicesBinding, SchedulerBinding, Semanti
             return Future<void>.value();
           debugPaintSizeEnabled = value;
           return _forceRepaint();
-        }
+        },
       );
       registerBoolServiceExtension(
         name: 'debugPaintBaselinesEnabled',
@@ -70,7 +70,7 @@ mixin RendererBinding on BindingBase, ServicesBinding, SchedulerBinding, Semanti
             return Future<void>.value();
           debugPaintBaselinesEnabled = value;
           return _forceRepaint();
-        }
+        },
       );
       registerBoolServiceExtension(
         name: 'repaintRainbow',
@@ -83,29 +83,44 @@ mixin RendererBinding on BindingBase, ServicesBinding, SchedulerBinding, Semanti
           return Future<void>.value();
         },
       );
+      registerSignalServiceExtension(
+        name: 'debugDumpLayerTree',
+        callback: () {
+          debugDumpLayerTree();
+          return debugPrintDone;
+        },
+      );
       return true;
     }());
 
+    const bool isReleaseMode = bool.fromEnvironment('dart.vm.product');
+    if (!isReleaseMode) {
+      // these service extensions work in debug or profile mode
       registerSignalServiceExtension(
         name: 'debugDumpRenderTree',
-      callback: () { debugDumpRenderTree(); return debugPrintDone; }
+        callback: () {
-    );
+          debugDumpRenderTree();
-
+          return debugPrintDone;
-    registerSignalServiceExtension(
+        },
-      name: 'debugDumpLayerTree',
-      callback: () { debugDumpLayerTree(); return debugPrintDone; }
       );
 
       registerSignalServiceExtension(
         name: 'debugDumpSemanticsTreeInTraversalOrder',
-      callback: () { debugDumpSemanticsTree(DebugSemanticsDumpOrder.traversalOrder); return debugPrintDone; }
+        callback: () {
+          debugDumpSemanticsTree(DebugSemanticsDumpOrder.traversalOrder);
+          return debugPrintDone;
+        },
       );
 
       registerSignalServiceExtension(
         name: 'debugDumpSemanticsTreeInInverseHitTestOrder',
-      callback: () { debugDumpSemanticsTree(DebugSemanticsDumpOrder.inverseHitTest); return debugPrintDone; }
+        callback: () {
+          debugDumpSemanticsTree(DebugSemanticsDumpOrder.inverseHitTest);
+          return debugPrintDone;
+        },
       );
     }
+  }
 
   /// Creates a [RenderView] object to be the root of the
   /// [RenderObject] rendering tree, and initializes it so that it

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

@@ -203,14 +203,18 @@ mixin SchedulerBinding on BindingBase, ServicesBinding {
   @override
   void initServiceExtensions() {
     super.initServiceExtensions();
+
+    const bool isReleaseMode = bool.fromEnvironment('dart.vm.product');
+    if (!isReleaseMode) {
       registerNumericServiceExtension(
         name: 'timeDilation',
         getter: () async => timeDilation,
         setter: (double value) async {
           timeDilation = value;
-      }
+        },
       );
     }
+  }
 
   /// Whether the application is visible, and if so, whether it is currently
   /// interactive.

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

@@ -86,6 +86,8 @@ mixin ServicesBinding on BindingBase {
   @override
   void initServiceExtensions() {
     super.initServiceExtensions();
+
+    assert(() {
       registerStringServiceExtension(
         // ext.flutter.evict value=foo.png will cause foo.png to be evicted from
         // the rootBundle cache and cause the entire image cache to be cleared.
@@ -95,8 +97,10 @@ mixin ServicesBinding on BindingBase {
         getter: () async => '',
         setter: (String value) async {
           evict(value);
-      }
+        },
       );
+      return true;
+    }());
   }
 
   /// Called in response to the `ext.flutter.evict` service extension.

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

@@ -265,25 +265,30 @@ mixin WidgetsBinding on BindingBase, SchedulerBinding, GestureBinding, RendererB
   void initServiceExtensions() {
     super.initServiceExtensions();
 
+    const bool isReleaseMode = bool.fromEnvironment('dart.vm.product');
+    if (!isReleaseMode) {
       registerSignalServiceExtension(
         name: 'debugDumpApp',
         callback: () {
           debugDumpApp();
           return debugPrintDone;
-      }
+        },
       );
 
       registerBoolServiceExtension(
         name: 'showPerformanceOverlay',
-      getter: () => Future<bool>.value(WidgetsApp.showPerformanceOverlayOverride),
+        getter: () =>
+        Future<bool>.value(WidgetsApp.showPerformanceOverlayOverride),
         setter: (bool value) {
           if (WidgetsApp.showPerformanceOverlayOverride == value)
             return Future<void>.value();
           WidgetsApp.showPerformanceOverlayOverride = value;
           return _forceRebuild();
-      }
+        },
       );
+    }
 
+    assert(() {
       registerBoolServiceExtension(
         name: 'debugAllowBanner',
         getter: () => Future<bool>.value(WidgetsApp.debugAllowBannerOverride),
@@ -292,10 +297,9 @@ mixin WidgetsBinding on BindingBase, SchedulerBinding, GestureBinding, RendererB
             return Future<void>.value();
           WidgetsApp.debugAllowBannerOverride = value;
           return _forceRebuild();
-      }
+        },
       );
 
-    assert(() {
       // Expose the ability to send Widget rebuilds as [Timeline] events.
       registerBoolServiceExtension(
         name: 'profileWidgetBuilds',
@@ -303,12 +307,10 @@ mixin WidgetsBinding on BindingBase, SchedulerBinding, GestureBinding, RendererB
         setter: (bool value) async {
           if (debugProfileBuildsEnabled != value)
             debugProfileBuildsEnabled = value;
-        }
+        },
       );
-      return true;
-    }());
 
-    // This service extension is deprecated and will be removed by 7/1/2018.
+      // This service extension is deprecated and will be removed by 12/1/2018.
       // Use ext.flutter.inspector.show instead.
       registerBoolServiceExtension(
           name: 'debugWidgetInspector',
@@ -322,6 +324,9 @@ mixin WidgetsBinding on BindingBase, SchedulerBinding, GestureBinding, RendererB
       );
 
       WidgetInspectorService.instance.initServiceExtensions(registerServiceExtension);
+
+      return true;
+    }());
   }
 
   Future<void> _forceRebuild() {

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

@@ -917,13 +917,11 @@ mixin WidgetInspectorService {
 
   /// Called to register service extensions.
   ///
-  /// Service extensions are only exposed when the observatory is
-  /// included in the build, which should only happen in checked mode
-  /// and in profile mode.
-  ///
   /// See also:
   ///
   ///  * <https://github.com/dart-lang/sdk/blob/master/runtime/vm/service/service.md#rpcs-requests-and-responses>
+  ///  * [BindingBase.initServiceExtensions], which explains when service
+  ///    extensions can be used.
   void initServiceExtensions(
       _RegisterServiceExtensionCallback registerServiceExtensionCallback) {
     _registerServiceExtensionCallback = registerServiceExtensionCallback;
@@ -1023,7 +1021,6 @@ mixin WidgetInspectorService {
       name: 'isWidgetCreationTracked',
       callback: isWidgetCreationTracked,
     );
-    assert(() {
     registerServiceExtension(
       name: 'screenshot',
       callback: (Map<String, String> parameters) async {
@@ -1051,8 +1048,6 @@ mixin WidgetInspectorService {
         };
       },
     );
-      return true;
-    }());
   }
 
   /// Clear all InspectorService object references.

packages/flutter/test/foundation/service_extensions_test.dart

@@ -359,13 +359,6 @@ void main() {
     expect(binding.extensions.containsKey('exit'), isTrue);
   });
 
-  test('Service extensions - frameworkPresent', () async {
-    Map<String, dynamic> result;
-
-    result = await binding.testExtension('frameworkPresent', <String, String>{});
-    expect(result, <String, String>{});
-  });
-
   test('Service extensions - platformOverride', () async {
     Map<String, dynamic> result;
 
@@ -491,7 +484,6 @@ void main() {
 
   test('Service extensions - debugWidgetInspector', () async {
     Map<String, dynamic> result;
-
     expect(binding.frameScheduled, isFalse);
     expect(WidgetsApp.debugShowWidgetInspectorOverride, false);
     result = await binding.testExtension('debugWidgetInspector', <String, String>{});
@@ -541,7 +533,7 @@ void main() {
 
     // If you add a service extension... TEST IT! :-)
     // ...then increment this number.
-    expect(binding.extensions.length, 39);
+    expect(binding.extensions.length, 38);
 
     expect(console, isEmpty);
     debugPrint = debugPrintThrottled;

packages/flutter_tools/lib/src/vmservice.dart

@@ -1296,10 +1296,6 @@ class Isolate extends ServiceObjectOwner {
     );
   }
 
-  Future<bool> flutterFrameworkPresent() async {
-    return await invokeFlutterExtensionRpcRaw('ext.flutter.frameworkPresent') != null;
-  }
-
   Future<Map<String, dynamic>> uiWindowScheduleFrame() async {
     return await invokeFlutterExtensionRpcRaw('ext.ui.window.scheduleFrame');
   }