Analysis cleanup of web tests (flutter#27670)

Author: ferhatb

lib/web_ui/analysis_options.yaml

@@ -13,11 +13,8 @@ analyzer:
 
 linter:
   rules:
-    annotate_overrides: false
     avoid_classes_with_only_static_members: false
-    avoid_empty_else: false
     avoid_function_literals_in_foreach_calls: false
-    avoid_init_to_null: false
     avoid_null_checks_in_equality_operators: false
     avoid_relative_lib_imports: false
     avoid_renaming_method_parameters: false
@@ -86,6 +83,6 @@ linter:
     unnecessary_string_interpolations: false
     cast_nullable_to_non_nullable: false
     flutter_style_todos: false
-    avoid_void_async: false
+
     # We have some legitimate use-cases for this (preserve tear-off identity)
-    prefer_function_declarations_over_variables: false
+    prefer_function_declarations_over_variables: false

lib/web_ui/dev/chrome.dart

@@ -209,6 +209,7 @@ Future<Uri> getRemoteDebuggerUrl(Uri base) async {
 /// This manager can be used for both macOS and Linux.
 // TODO: https://github.com/flutter/flutter/issues/65673
 class ChromeScreenshotManager extends ScreenshotManager {
+  @override
   String get filenameSuffix => '';
 
   /// Capture a screenshot of the web content.
@@ -218,6 +219,7 @@ class ChromeScreenshotManager extends ScreenshotManager {
   /// [region] is used to decide which part of the web content will be used in
   /// test image. It includes starting coordinate x,y as well as height and
   /// width of the area to capture.
+  @override
   Future<Image> capture(math.Rectangle<num>? region) async {
     final wip.ChromeConnection chromeConnection =
         wip.ChromeConnection('localhost', kDevtoolsPort);
@@ -230,7 +232,7 @@ class ChromeScreenshotManager extends ScreenshotManager {
     }
     final wip.WipConnection wipConnection = await chromeTab.connect();
 
-    Map<String, dynamic>? captureScreenshotParameters = null;
+    Map<String, dynamic>? captureScreenshotParameters;
     if (region != null) {
       captureScreenshotParameters = <String, dynamic>{
         'format': 'png',

lib/web_ui/dev/common.dart

@@ -140,6 +140,7 @@ class _MacBinding implements PlatformBinding {
   String getChromeDownloadUrl(String version) =>
       '$_kBaseDownloadUrl/Mac%2F$version%2Fchrome-mac.zip?alt=media';
 
+  @override
   String getChromeExecutablePath(io.Directory versionDir) => path.join(
       versionDir.path,
       'chrome-mac',

lib/web_ui/dev/felt.dart

@@ -24,7 +24,7 @@ CommandRunner<bool> runner = CommandRunner<bool>(
   ..addCommand(TestCommand())
   ..addCommand(BuildCommand());
 
-void main(List<String> rawArgs) async {
+Future<void> main(List<String> rawArgs) async {
   // Remove --clean from the list as that's processed by the wrapper script.
   final List<String> args = rawArgs.where((String arg) => arg != '--clean').toList();
 
@@ -69,7 +69,7 @@ void main(List<String> rawArgs) async {
   io.exit(io.exitCode);
 }
 
-void _listenToShutdownSignals() async {
+Future<void> _listenToShutdownSignals() async {
   io.ProcessSignal.sigint.watch().listen((_) async {
     print('Received SIGINT. Shutting down.');
     await cleanup();

lib/web_ui/dev/safari_installation.dart

@@ -65,6 +65,7 @@ class IosSafariArgParser extends BrowserArgParser {
   /// The [IosSafariArgParser] singleton.
   static IosSafariArgParser get instance => _singletonInstance;
 
+  @override
   String get version => 'iOS ${iosMajorVersion}.${iosMinorVersion}';
 
   final int _pinnedIosMajorVersion;

lib/web_ui/dev/safari_ios.dart

@@ -79,6 +79,7 @@ class SafariIos extends Browser {
 ///
 /// This manager will only be created/used for macOS.
 class SafariIosScreenshotManager extends ScreenshotManager {
+  @override
   String get filenameSuffix => '.iOS_Safari';
 
   SafariIosScreenshotManager() {
@@ -154,6 +155,7 @@ class SafariIosScreenshotManager extends ScreenshotManager {
   /// width of the area to capture.
   ///
   /// Uses simulator tool `xcrun simctl`'s 'screenshot' command.
+  @override
   Future<Image> capture(math.Rectangle<num>? region) async {
     final String filename = 'screenshot${_fileNameCounter}.png';
     _fileNameCounter++;

lib/web_ui/dev/test_platform.dart

@@ -371,6 +371,7 @@ class BrowserPlatform extends PlatformPlugin {
     return suite;
   }
 
+  @override
   StreamChannel<dynamic> loadChannel(String path, SuitePlatform platform) =>
       throw UnimplementedError();
 
@@ -413,6 +414,7 @@ class BrowserPlatform extends PlatformPlugin {
   ///
   /// Note that this doesn't close the server itself. Browser tests can still be
   /// loaded, they'll just spawn new browsers.
+  @override
   Future<void> closeEphemeral() async {
     if (_browserManager != null) {
       final BrowserManager? result = await _browserManager!;
@@ -424,6 +426,7 @@ class BrowserPlatform extends PlatformPlugin {
   ///
   /// Returns a [Future] that completes once the server is closed and its
   /// resources have been fully released.
+  @override
   Future<void> close() {
     return _closeMemo.runOnce(() async {
       final List<Future<void>> futures = <Future<void>>[];
@@ -780,17 +783,22 @@ class BrowserManager {
 class _BrowserEnvironment implements Environment {
   final BrowserManager _manager;
 
+  @override
   final bool supportsDebugging = true;
 
+  @override
   final Uri? observatoryUrl;
 
+  @override
   final Uri? remoteDebuggerUrl;
 
+  @override
   final Stream<dynamic> onRestart;
 
   _BrowserEnvironment(this._manager, this.observatoryUrl,
       this.remoteDebuggerUrl, this.onRestart);
 
+  @override
   CancelableOperation<void> displayPause() => _manager._displayPause();
 }
 

lib/web_ui/dev/watcher.dart

@@ -226,7 +226,7 @@ class PipelineWatcher {
     });
   }
 
-  void _runPipeline() async {
+  Future<void> _runPipeline() async {
     if (pipeline.status == PipelineStatus.stopping) {
       // We are already trying to stop the pipeline. No need to do anything.
       return;

lib/web_ui/lib/src/engine/canvas_pool.dart

@@ -476,6 +476,7 @@ class CanvasPool extends _SaveStackTracking {
     }
   }
 
+  @override
   void clipRect(ui.Rect rect) {
     super.clipRect(rect);
     if (_canvas != null) {
@@ -489,6 +490,7 @@ class CanvasPool extends _SaveStackTracking {
     ctx.clip();
   }
 
+  @override
   void clipRRect(ui.RRect rrect) {
     super.clipRRect(rrect);
     if (_canvas != null) {
@@ -502,6 +504,7 @@ class CanvasPool extends _SaveStackTracking {
     ctx.clip();
   }
 
+  @override
   void clipPath(ui.Path path) {
     super.clipPath(path);
     if (_canvas != null) {

lib/web_ui/lib/src/engine/canvaskit/color_filter.dart

@@ -73,6 +73,7 @@ abstract class CkColorFilter
   /// filter is used as a [ColorFilter].
   SkColorFilter _initRawColorFilter();
 
+  @override
   ManagedSkiaObject<SkImageFilter> get imageFilter =>
       CkColorFilterImageFilter(colorFilter: this);
 }

lib/web_ui/lib/src/engine/canvaskit/embedded_views.dart

@@ -536,6 +536,7 @@ class EmbeddedViewParams {
   final ui.Size size;
   final MutatorsStack mutators;
 
+  @override
   bool operator ==(Object other) {
     if (identical(this, other)) {
       return true;
@@ -546,6 +547,7 @@ class EmbeddedViewParams {
         other.mutators == mutators;
   }
 
+  @override
   int get hashCode => ui.hashValues(offset, size, mutators);
 }
 
@@ -593,6 +595,7 @@ class Mutator {
 
   double get alphaFloat => alpha! / 255.0;
 
+  @override
   bool operator ==(Object other) {
     if (identical(this, other)) {
       return true;
@@ -622,6 +625,7 @@ class Mutator {
     }
   }
 
+  @override
   int get hashCode => ui.hashValues(type, rect, rrect, path, matrix, alpha);
 }
 
@@ -658,6 +662,7 @@ class MutatorsStack extends Iterable<Mutator> {
     _mutators.removeLast();
   }
 
+  @override
   bool operator ==(Object other) {
     if (identical(other, this)) {
       return true;
@@ -666,6 +671,7 @@ class MutatorsStack extends Iterable<Mutator> {
         listEquals<Mutator>(other._mutators, _mutators);
   }
 
+  @override
   int get hashCode => ui.hashList(_mutators);
 
   @override

lib/web_ui/lib/src/engine/canvaskit/image_filter.dart

@@ -141,6 +141,7 @@ class _CkMatrixImageFilter extends CkImageFilter {
   final Float64List matrix;
   final ui.FilterQuality filterQuality;
 
+  @override
   SkImageFilter _initSkiaObject() {
     return canvasKit.ImageFilter.MakeMatrixTransform(
       toSkMatrixFromFloat64(matrix),

lib/web_ui/lib/src/engine/canvaskit/layer.dart

@@ -41,6 +41,7 @@ abstract class Layer implements ui.EngineLayer {
 
   // TODO(dnfield): Implement ui.EngineLayer.dispose for CanvasKit.
   // https://github.com/flutter/flutter/issues/82878
+  @override
   void dispose() {}
 }
 

lib/web_ui/lib/src/engine/canvaskit/layer_scene_builder.dart

@@ -146,6 +146,7 @@ class LayerSceneBuilder implements ui.SceneBuilder {
     return pushLayer<ColorFilterEngineLayer>(ColorFilterEngineLayer(filter));
   }
 
+  @override
   ImageFilterEngineLayer pushImageFilter(
     ui.ImageFilter filter, {
     ui.ImageFilterEngineLayer? oldLayer,

lib/web_ui/lib/src/engine/html/bitmap_canvas.dart

@@ -68,7 +68,7 @@ class BitmapCanvas extends EngineCanvas {
 
   /// The last CSS font string is cached to optimize the case where the font
   /// styles hasn't changed.
-  String? _cachedLastCssFont = null;
+  String? _cachedLastCssFont;
 
   /// List of extra sibling elements created for paragraphs and clipping.
   final List<html.Element> _children = <html.Element>[];

lib/web_ui/lib/src/engine/html/path/path_metrics.dart

@@ -551,6 +551,7 @@ class SurfacePathMetric implements ui.PathMetric {
   /// have been implied when using methods like [Path.addRect]) or if
   /// `forceClosed` was specified as true in the call to [Path.computeMetrics].
   /// Returns false otherwise.
+  @override
   final bool isClosed;
 
   /// The zero-based index of the contour.
@@ -565,6 +566,7 @@ class SurfacePathMetric implements ui.PathMetric {
   /// the contours of the path at the time the path's metrics were computed. If
   /// additional contours were added or existing contours updated, this metric
   /// will be invalid for the current state of the path.
+  @override
   final int contourIndex;
 
   final _SurfacePathMeasure _measure;
@@ -588,6 +590,7 @@ class SurfacePathMetric implements ui.PathMetric {
   ///
   /// `start` and `end` are pinned to legal values (0..[length])
   /// Begin the segment with a moveTo if `startWithMoveTo` is true.
+  @override
   ui.Path extractPath(double start, double end, {bool startWithMoveTo = true}) {
     return _measure.extractPath(contourIndex, start, end,
         startWithMoveTo: startWithMoveTo);

lib/web_ui/lib/src/engine/html/path/path_ref.dart

@@ -301,6 +301,7 @@ class PathRef {
         bottomLeft: radii[_Corner.kLowerLeft]);
   }
 
+  @override
   bool operator ==(Object other) {
     if (identical(this, other)) {
       return true;

lib/web_ui/lib/src/engine/html/render_vertices.dart

@@ -302,6 +302,7 @@ class _WebGlRenderer implements GlRenderer {
   ///
   /// Browsers that support OffscreenCanvas and the transferToImageBitmap api
   /// will return ImageBitmap, otherwise will return CanvasElement.
+  @override
   Object? drawRect(ui.Rect targetRect, GlContext gl, GlProgram glProgram,
       NormalizedGradient gradient, int widthInPixels, int heightInPixels) {
     drawRectToGl(
@@ -314,6 +315,7 @@ class _WebGlRenderer implements GlRenderer {
 
   /// Renders a rectangle using given program into an image resource and returns
   /// url.
+  @override
   String drawRectToImageUrl(
       ui.Rect targetRect,
       GlContext gl,

lib/web_ui/lib/src/engine/html/scene.dart

@@ -20,13 +20,15 @@ class SurfaceScene implements ui.Scene {
 
   /// Creates a raster image representation of the current state of the scene.
   /// This is a slow operation that is performed on a background thread.
+  @override
   Future<ui.Image> toImage(int width, int height) {
     throw UnsupportedError('toImage is not supported on the Web');
   }
 
   /// Releases the resources used by this scene.
   ///
   /// After calling this function, the scene is cannot be used further.
+  @override
   void dispose() {}
 }
 

lib/web_ui/lib/src/engine/html/shaders/shader.dart

@@ -698,6 +698,7 @@ class _BlurEngineImageFilter extends EngineImageFilter {
   final ui.TileMode tileMode;
 
   // TODO(flutter_web): implement TileMode.
+  @override
   String get filterAttribute => blurSigmasToCssString(sigmaX, sigmaY);
 
   @override
@@ -728,6 +729,7 @@ class _MatrixEngineImageFilter extends EngineImageFilter {
   final ui.FilterQuality filterQuality;
 
   // TODO(flutter_web): implement FilterQuality.
+  @override
   String get transformAttribute => float64ListToCssTransform(webMatrix);
 
   @override