Enable dispose-class-fields and dispose-fields lints to resolve memory leaks (#9857)

Author: kenzieschmoll

.github/workflows/build.yaml

@@ -74,7 +74,7 @@ jobs:
           wget -qO- https://dcm.dev/pgp-key.public | sudo gpg --dearmor -o /usr/share/keyrings/dcm.gpg
           echo 'deb [signed-by=/usr/share/keyrings/dcm.gpg arch=amd64] https://dcm.dev/debian stable main' | sudo tee /etc/apt/sources.list.d/dart_stable.list
           sudo apt-get update
-          sudo apt-get install dcm=1.36.0-1 # To avoid errors add `-1` (build number) to the version
+          sudo apt-get install dcm=1.38.1-1 # To avoid errors add `-1` (build number) to the version
           sudo chmod +x /usr/bin/dcm
           echo "$(dcm --version)"
       - name: Setup Dart SDK

analysis_options.yaml

@@ -186,6 +186,8 @@ dart_code_metrics:
     - avoid-explicit-type-declaration
     # - ban-name # TODO(polina-c): add configuration
     # - binary-expression-operand-order Some nice catches but too many false positives to enable.
+    - dispose-class-fields
+    - dispose-fields
     - double-literal-format
     # - format-comment TODO(jacobr): enable this one after fixing violations.
     # TODO(jacobr): enable member-ordering. This catches a bunch of real style

packages/devtools_app/lib/src/app.dart

@@ -202,6 +202,7 @@ class DevToolsAppState extends State<DevToolsApp> with AutoDisposeMixin {
     FrameworkCore.dispose();
     // Workaround for https://github.com/flutter/flutter/issues/155265.
     removeTextFieldFocusFixHandler();
+    routerDelegate.dispose();
     super.dispose();
   }
 

packages/devtools_app/lib/src/extensions/embedded/_view_web.dart

@@ -46,6 +46,7 @@ class _EmbeddedExtensionState extends State<EmbeddedExtension>
 
   @override
   void dispose() {
+    _embeddedExtensionController.dispose();
     iFrameController.dispose();
     super.dispose();
   }

packages/devtools_app/lib/src/framework/notifications_view.dart

@@ -86,7 +86,10 @@ class _NotificationsState extends State<_Notifications> with AutoDisposeMixin {
 
   @override
   void dispose() {
-    _overlayEntry!.remove();
+    _overlayEntry
+      ?..remove()
+      ..dispose();
+    _overlayEntry = null;
     super.dispose();
   }
 
@@ -218,6 +221,7 @@ class _NotificationState extends State<_Notification>
   void dispose() {
     controller.dispose();
     _dismissTimer?.cancel();
+    curve.dispose();
     super.dispose();
   }
 

packages/devtools_app/lib/src/screens/debugger/debugger_controller.dart

@@ -89,6 +89,8 @@ class DebuggerController extends DevToolsScreenController
     _selectedBreakpoint.dispose();
     _exceptionPauseMode.dispose();
     _hasTruncatedFrames.dispose();
+    unawaited(_getStackOperation?.cancel());
+    _lastService = null;
     super.dispose();
   }
 

packages/devtools_app/lib/src/screens/inspector/inspector_controller.dart

@@ -200,7 +200,8 @@ class InspectorController extends DisposableController
   /// for now mainly to minimize risk.
   static const refreshFramesPerSecond = 5.0;
 
-  InspectorTreeController inspectorTree;
+  final InspectorTreeController inspectorTree;
+
   final FlutterTreeType treeType;
 
   late RateLimiter _refreshRateLimiter;

packages/devtools_app/lib/src/screens/inspector/inspector_tree_controller.dart

@@ -914,6 +914,8 @@ class _InspectorTreeState extends State<InspectorTree>
   Rect? _currentAnimateTarget;
 
   AnimationController? _constraintDisplayController;
+
+  // ignore: dispose-fields, false positive. Disposed via autoDisposeFocusNode.
   late FocusNode _focusNode;
 
   /// When autoscrolling, the number of rows to pad the target location with.

packages/devtools_app/lib/src/screens/inspector/layout_explorer/flex/flex.dart

@@ -394,6 +394,12 @@ class FlexLayoutExplorerWidgetState
       ),
     );
   }
+
+  @override
+  void dispose() {
+    scrollController.dispose();
+    super.dispose();
+  }
 }
 
 class VisualizeFlexChildren extends StatefulWidget {

packages/devtools_app/lib/src/screens/inspector/layout_explorer/ui/layout_explorer_widget.dart

@@ -162,6 +162,9 @@ abstract class LayoutExplorerWidgetState<
     entranceController.dispose();
     changeController.dispose();
     _unregisterInspectorControllerService();
+    entranceCurve.dispose();
+    changeAnimation.dispose();
+    rateLimiter.dispose();
     super.dispose();
   }