Analyze code snippets in flutter_test docs (#132246)

Fixes https://github.com/flutter/flutter/issues/132274.

dev/bots/analyze_snippet_code.dart

@@ -70,7 +70,8 @@ import 'package:path/path.dart' as path;
 import 'package:watcher/watcher.dart';
 
 final String _flutterRoot = path.dirname(path.dirname(path.dirname(path.fromUri(Platform.script))));
-final String _defaultFlutterPackage = path.join(_flutterRoot, 'packages', 'flutter', 'lib');
+final String _packageFlutter = path.join(_flutterRoot, 'packages', 'flutter', 'lib');
+final String _packageFlutterTest = path.join(_flutterRoot, 'packages', 'flutter_test', 'lib');
 final String _defaultDartUiLocation = path.join(_flutterRoot, 'bin', 'cache', 'pkg', 'sky_engine', 'lib', 'ui');
 final String _flutter = path.join(_flutterRoot, 'bin', Platform.isWindows ? 'flutter.bat' : 'flutter');
 
@@ -142,12 +143,16 @@ Future<void> main(List<String> arguments) async {
     exit(0);
   }
 
-  Directory flutterPackage;
+  List<Directory> flutterPackages;
   if (parsedArguments.rest.length == 1) {
     // Used for testing.
-    flutterPackage = Directory(parsedArguments.rest.single);
+    flutterPackages = <Directory>[Directory(parsedArguments.rest.single)];
   } else {
-    flutterPackage = Directory(_defaultFlutterPackage);
+    flutterPackages = <Directory>[
+      Directory(_packageFlutter),
+      Directory(_packageFlutterTest),
+      // TODO(goderbauer): Add all other packages.
+    ];
   }
 
   final bool includeDartUi = parsedArguments.wasParsed('dart-ui-location') || parsedArguments['include-dart-ui'] as bool;
@@ -165,14 +170,14 @@ Future<void> main(List<String> arguments) async {
 
   if (parsedArguments['interactive'] != null) {
     await _runInteractive(
-      flutterPackage: flutterPackage,
+      flutterPackages: flutterPackages,
       tempDirectory: parsedArguments['temp'] as String?,
       filePath: parsedArguments['interactive'] as String,
       dartUiLocation: includeDartUi ? dartUiLocation : null,
     );
   } else {
     if (await _SnippetChecker(
-        flutterPackage,
+        flutterPackages,
         tempDirectory: parsedArguments['temp'] as String?,
         verbose: parsedArguments['verbose'] as bool,
         dartUiLocation: includeDartUi ? dartUiLocation : null,
@@ -360,7 +365,7 @@ class _SnippetChecker {
   /// supplied, the default location of the `dart:ui` code in the Flutter
   /// repository is used (i.e. "<flutter repo>/bin/cache/pkg/sky_engine/lib/ui").
   _SnippetChecker(
-    this._flutterPackage, {
+    this._flutterPackages, {
     String? tempDirectory,
     this.verbose = false,
     Directory? dartUiLocation,
@@ -438,8 +443,8 @@ class _SnippetChecker {
   /// automatically if there are no errors unless _keepTmp is true.
   final Directory _tempDirectory;
 
-  /// The package directory for the flutter package within the flutter root dir.
-  final Directory _flutterPackage;
+  /// The package directories within the flutter root dir that will be checked.
+  final List<Directory> _flutterPackages;
 
   /// The directory for the dart:ui code to be analyzed with the flutter code.
   ///
@@ -481,7 +486,7 @@ class _SnippetChecker {
       "import 'dart:typed_data';",
       "import 'dart:ui' as ui;",
       "import 'package:flutter_test/flutter_test.dart';",
-      for (final File file in _listDartFiles(Directory(_defaultFlutterPackage)))
+      for (final File file in _listDartFiles(Directory(_packageFlutter)))
         "import 'package:flutter/${path.basename(file.path)}';",
     ].map<_Line>((String code) => _Line.generated(code: code)).toList();
   }
@@ -495,7 +500,8 @@ class _SnippetChecker {
       stderr.writeln('Unable to analyze engine dart snippets at ${_dartUiLocation!.path}.');
     }
     final List<File> filesToAnalyze = <File>[
-      ..._listDartFiles(_flutterPackage, recursive: true),
+      for (final Directory flutterPackage in _flutterPackages)
+        ..._listDartFiles(flutterPackage, recursive: true),
       if (_dartUiLocation != null && _dartUiLocation!.existsSync())
         ..._listDartFiles(_dartUiLocation!, recursive: true),
     ];
@@ -1084,7 +1090,7 @@ class _SnippetFile {
 
 Future<void> _runInteractive({
   required String? tempDirectory,
-  required Directory flutterPackage,
+  required List<Directory> flutterPackages,
   required String filePath,
   required Directory? dartUiLocation,
 }) async {
@@ -1106,7 +1112,7 @@ Future<void> _runInteractive({
   print('Starting up in interactive mode on ${path.relative(filePath, from: _flutterRoot)} ...');
   print('Type "q" to quit, or "r" to force a reload.');
 
-  final _SnippetChecker checker = _SnippetChecker(flutterPackage, tempDirectory: tempDirectory)
+  final _SnippetChecker checker = _SnippetChecker(flutterPackages, tempDirectory: tempDirectory)
     .._createConfigurationFiles();
 
   ProcessSignal.sigint.watch().listen((_) {

packages/flutter_test/lib/flutter_test.dart

@@ -27,7 +27,7 @@
 /// with the following signature:
 ///
 /// ```dart
-/// Future<void> testExecutable(FutureOr<void> Function() testMain);
+/// Future<void> testExecutable(FutureOr<void> Function() testMain) async { }
 /// ```
 ///
 /// The test framework will execute that method and pass it the `main()` method

packages/flutter_test/lib/src/accessibility.dart

@@ -57,6 +57,9 @@ class Evaluation {
   }
 }
 
+// Examples can assume:
+// typedef HomePage = Placeholder;
+
 /// An accessibility guideline describes a recommendation an application should
 /// meet to be considered accessible.
 ///

packages/flutter_test/lib/src/animation_sheet.dart

@@ -55,14 +55,14 @@ import 'package:flutter/widgets.dart';
 ///   // Start recording (`recording` is true)
 ///   await tester.pumpFrames(animationSheet.record(
 ///     target,
-///     recording: true,
+///     recording: true, // ignore: avoid_redundant_argument_values
 ///   ), const Duration(seconds: 1));
 ///
 ///   await gesture.up();
 ///
 ///   await tester.pumpFrames(animationSheet.record(
 ///     target,
-///     recording: true,
+///     recording: true, // ignore: avoid_redundant_argument_values
 ///   ), const Duration(seconds: 1));
 ///
 ///   // Compare against golden file

packages/flutter_test/lib/src/binding.dart

@@ -143,6 +143,10 @@ class CapturedAccessibilityAnnouncement {
   final Assertiveness assertiveness;
 }
 
+// Examples can assume:
+// late TestWidgetsFlutterBinding binding;
+// late Size someSize;
+
 /// Base class for bindings used by widgets library tests.
 ///
 /// The [ensureInitialized] method creates (if necessary) and returns an
@@ -1548,7 +1552,7 @@ class AutomatedTestWidgetsFlutterBinding extends TestWidgetsFlutterBinding {
 /// ```dart
 /// TestWidgetsFlutterBinding binding = TestWidgetsFlutterBinding.ensureInitialized();
 /// if (binding is LiveTestWidgetsFlutterBinding) {
-///   binding.framePolicy = LiveTestWidgetsFlutterBindingFramePolicy.[thePolicy];
+///   binding.framePolicy = LiveTestWidgetsFlutterBindingFramePolicy.onlyPumps;
 /// }
 /// ```
 /// {@endtemplate}

packages/flutter_test/lib/src/buffer_matcher.dart

-// 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:typed_data';
-
-import 'package:matcher/expect.dart' show Description;
-import 'package:matcher/src/expect/async_matcher.dart'; // ignore: implementation_imports
-import 'package:test_api/hooks.dart' show TestFailure;
-
-import 'goldens.dart';
-
-/// Matcher created by [bufferMatchesGoldenFile].
-class _BufferGoldenMatcher extends AsyncMatcher {
-  /// Creates an instance of [BufferGoldenMatcher]. Called by [bufferMatchesGoldenFile].
-  const _BufferGoldenMatcher(this.key, this.version);
-
-  /// The [key] to the golden image.
-  final Uri key;
-
-  /// The [version] of the golden image.
-  final int? version;
-
-  @override
-  Future<String?> matchAsync(dynamic item) async {
-    Uint8List buffer;
-    if (item is List<int>) {
-      buffer = Uint8List.fromList(item);
-    } else if (item is Future<List<int>>) {
-      buffer = Uint8List.fromList(await item);
-    } else {
-      throw AssertionError('Expected `List<int>` or `Future<List<int>>`, instead found: ${item.runtimeType}');
-    }
-    final Uri testNameUri = goldenFileComparator.getTestUri(key, version);
-    if (autoUpdateGoldenFiles) {
-      await goldenFileComparator.update(testNameUri, buffer);
-      return null;
-    }
-    try {
-      final bool success = await goldenFileComparator.compare(buffer, testNameUri);
-      return success ? null : 'does not match';
-    } on TestFailure catch (ex) {
-      return ex.message;
-    }
-  }
-
-  @override
-  Description describe(Description description) {
-    final Uri testNameUri = goldenFileComparator.getTestUri(key, version);
-    return description.add('Byte buffer matches golden image "$testNameUri"');
-  }
-}
-
-/// Asserts that a [Future<List<int>>], or [List<int] matches the
-/// golden image file identified by [key], with an optional [version] number.
-///
-/// The [key] is the [String] representation of a URL.
-///
-/// The [version] is a number that can be used to differentiate historical
-/// golden files. This parameter is optional.
-///
-/// {@tool snippet}
-/// Sample invocations of [bufferMatchesGoldenFile].
-///
-/// ```dart
-/// await expectLater(
-///   const <int>[ /* bytes... */ ],
-///   bufferMatchesGoldenFile('sample.png'),
-/// );
-/// ```
-/// {@end-tool}
-AsyncMatcher bufferMatchesGoldenFile(String key, {int? version}) {
-   return _BufferGoldenMatcher(Uri.parse(key), version);
-}

packages/flutter_test/lib/src/controller.dart

@@ -24,6 +24,9 @@ const double kDragSlopDefault = 20.0;
 
 const String _defaultPlatform = kIsWeb ? 'web' : 'android';
 
+// Examples can assume:
+// typedef MyWidget = Placeholder;
+
 /// Class that programmatically interacts with the [Semantics] tree.
 ///
 /// Allows for testing of the [Semantics] tree, which is used by assistive
@@ -123,13 +126,13 @@ class SemanticsController {
   ///
   /// ## Sample Code
   ///
-  /// ```
+  /// ```dart
   /// testWidgets('MyWidget', (WidgetTester tester) async {
-  ///   await tester.pumpWidget(MyWidget());
+  ///   await tester.pumpWidget(const MyWidget());
   ///
   ///   expect(
   ///     tester.semantics.simulatedAccessibilityTraversal(),
-  ///     containsAllInOrder([
+  ///     containsAllInOrder(<Matcher>[
   ///       containsSemantics(label: 'My Widget'),
   ///       containsSemantics(label: 'is awesome!', isChecked: true),
   ///     ]),

packages/flutter_test/lib/src/finders.dart

@@ -17,6 +17,12 @@ typedef ElementPredicate = bool Function(Element element);
 /// Some frequently used widget [Finder]s.
 const CommonFinders find = CommonFinders._();
 
+// Examples can assume:
+// typedef Button = Placeholder;
+// late WidgetTester tester;
+// late String filePath;
+// late Key backKey;
+
 /// Provides lightweight syntax for getting frequently used widget [Finder]s.
 ///
 /// This class is instantiated once, as [find].
@@ -116,9 +122,9 @@ class CommonFinders {
   ///
   /// ```dart
   /// // Suppose you have a button with text 'Update' in it:
-  /// Button(
+  /// const Button(
   ///   child: Text('Update')
-  /// )
+  /// );
   ///
   /// // You can find and tap on it like this:
   /// tester.tap(find.widgetWithText(Button, 'Update'));
@@ -217,9 +223,9 @@ class CommonFinders {
   ///
   /// ```dart
   /// // Suppose you have a button with icon 'arrow_forward' in it:
-  /// Button(
+  /// const Button(
   ///   child: Icon(Icons.arrow_forward)
-  /// )
+  /// );
   ///
   /// // You can find and tap on it like this:
   /// tester.tap(find.widgetWithIcon(Button, Icons.arrow_forward));
@@ -242,11 +248,11 @@ class CommonFinders {
   /// ```dart
   /// // Suppose you have a button with image in it:
   /// Button(
-  ///   child: Image.file(filePath)
-  /// )
+  ///   child: Image.file(File(filePath))
+  /// );
   ///
   /// // You can find and tap on it like this:
-  /// tester.tap(find.widgetWithImage(Button, FileImage(filePath)));
+  /// tester.tap(find.widgetWithImage(Button, FileImage(File(filePath))));
   /// ```
   ///
   /// If the `skipOffstage` argument is true (the default), then this skips
@@ -283,7 +289,7 @@ class CommonFinders {
   ///
   /// ```dart
   /// // Suppose you have a button created like this:
-  /// Widget myButton = Button(
+  /// Widget myButton = const Button(
   ///   child: Text('Update')
   /// );
   ///
@@ -396,7 +402,7 @@ class CommonFinders {
   ///   tester.widget<Opacity>(
   ///     find.ancestor(
   ///       of: find.text('faded'),
-  ///       matching: find.byType('Opacity'),
+  ///       matching: find.byType(Opacity),
   ///     )
   ///   ).opacity,
   ///   0.5

packages/flutter_test/lib/src/matchers.dart

@@ -331,6 +331,13 @@ Matcher isMethodCall(String name, { required dynamic arguments }) {
 Matcher coversSameAreaAs(Path expectedPath, { required Rect areaToCompare, int sampleSize = 20 })
   => _CoversSameAreaAs(expectedPath, areaToCompare: areaToCompare, sampleSize: sampleSize);
 
+// Examples can assume:
+// late Image image;
+// late Future<Image> imageFuture;
+// typedef MyWidget = Placeholder;
+// late Future<ByteData> someFont;
+// late WidgetTester tester;
+
 /// Asserts that a [Finder], [Future<ui.Image>], or [ui.Image] matches the
 /// golden image file identified by [key], with an optional [version] number.
 ///
@@ -404,18 +411,18 @@ Matcher coversSameAreaAs(Path expectedPath, { required Rect areaToCompare, int s
 /// {@tool snippet}
 /// How to load a custom font for golden images.
 /// ```dart
-/// testWidgets('Creating a golden image with a custom font', (tester) async {
+/// testWidgets('Creating a golden image with a custom font', (WidgetTester tester) async {
 ///   // Assuming the 'Roboto.ttf' file is declared in the pubspec.yaml file
-///   final font = rootBundle.load('path/to/font-file/Roboto.ttf');
+///   final Future<ByteData> font = rootBundle.load('path/to/font-file/Roboto.ttf');
 ///
-///   final fontLoader = FontLoader('Roboto')..addFont(font);
+///   final FontLoader fontLoader = FontLoader('Roboto')..addFont(font);
 ///   await fontLoader.load();
 ///
-///   await tester.pumpWidget(const SomeWidget());
+///   await tester.pumpWidget(const MyWidget());
 ///
 ///   await expectLater(
-///     find.byType(SomeWidget),
-///     matchesGoldenFile('someWidget.png'),
+///     find.byType(MyWidget),
+///     matchesGoldenFile('myWidget.png'),
 ///   );
 /// });
 /// ```
@@ -431,7 +438,7 @@ Matcher coversSameAreaAs(Path expectedPath, { required Rect areaToCompare, int s
 /// ```dart
 /// Future<void> testExecutable(FutureOr<void> Function() testMain) async {
 ///   setUpAll(() async {
-///     final fontLoader = FontLoader('SomeFont')..addFont(someFont);
+///     final FontLoader fontLoader = FontLoader('SomeFont')..addFont(someFont);
 ///     await fontLoader.load();
 ///   });
 ///
@@ -473,18 +480,20 @@ AsyncMatcher matchesGoldenFile(Object key, {int? version}) {
 /// ## Sample code
 ///
 /// ```dart
-/// final ui.Paint paint = ui.Paint()
-///   ..style = ui.PaintingStyle.stroke
-///   ..strokeWidth = 1.0;
-/// final ui.PictureRecorder recorder = ui.PictureRecorder();
-/// final ui.Canvas pictureCanvas = ui.Canvas(recorder);
-/// pictureCanvas.drawCircle(Offset.zero, 20.0, paint);
-/// final ui.Picture picture = recorder.endRecording();
-/// ui.Image referenceImage = picture.toImage(50, 50);
-///
-/// await expectLater(find.text('Save'), matchesReferenceImage(referenceImage));
-/// await expectLater(image, matchesReferenceImage(referenceImage);
-/// await expectLater(imageFuture, matchesReferenceImage(referenceImage));
+/// testWidgets('matchesReferenceImage', (WidgetTester tester) async {
+///   final ui.Paint paint = ui.Paint()
+///     ..style = ui.PaintingStyle.stroke
+///     ..strokeWidth = 1.0;
+///   final ui.PictureRecorder recorder = ui.PictureRecorder();
+///   final ui.Canvas pictureCanvas = ui.Canvas(recorder);
+///   pictureCanvas.drawCircle(Offset.zero, 20.0, paint);
+///   final ui.Picture picture = recorder.endRecording();
+///   ui.Image referenceImage = await picture.toImage(50, 50);
+///
+///   await expectLater(find.text('Save'), matchesReferenceImage(referenceImage));
+///   await expectLater(image, matchesReferenceImage(referenceImage));
+///   await expectLater(imageFuture, matchesReferenceImage(referenceImage));
+/// });
 /// ```
 ///
 /// See also:
@@ -508,9 +517,12 @@ AsyncMatcher matchesReferenceImage(ui.Image image) {
 /// ## Sample code
 ///
 /// ```dart
-/// final SemanticsHandle handle = tester.ensureSemantics();
-/// expect(tester.getSemantics(find.text('hello')), matchesSemantics(label: 'hello'));
-/// handle.dispose();
+/// testWidgets('matchesSemantics', (WidgetTester tester) async {
+///   final SemanticsHandle handle = tester.ensureSemantics();
+///   // ...
+///   expect(tester.getSemantics(find.text('hello')), matchesSemantics(label: 'hello'));
+///   handle.dispose();
+/// });
 /// ```
 ///
 /// See also:
@@ -685,9 +697,12 @@ Matcher matchesSemantics({
 /// ## Sample code
 ///
 /// ```dart
-/// final SemanticsHandle handle = tester.ensureSemantics();
-/// expect(tester.getSemantics(find.text('hello')), hasSemantics(label: 'hello'));
-/// handle.dispose();
+/// testWidgets('containsSemantics', (WidgetTester tester) async {
+///   final SemanticsHandle handle = tester.ensureSemantics();
+///   // ...
+///   expect(tester.getSemantics(find.text('hello')), containsSemantics(label: 'hello'));
+///   handle.dispose();
+/// });
 /// ```
 ///
 /// See also:
@@ -859,9 +874,12 @@ Matcher containsSemantics({
 /// ## Sample code
 ///
 /// ```dart
-/// final SemanticsHandle handle = tester.ensureSemantics();
-/// await expectLater(tester, meetsGuideline(textContrastGuideline));
-/// handle.dispose();
+/// testWidgets('containsSemantics', (WidgetTester tester) async {
+///   final SemanticsHandle handle = tester.ensureSemantics();
+///   // ...
+///   await expectLater(tester, meetsGuideline(textContrastGuideline));
+///   handle.dispose();
+/// });
 /// ```
 ///
 /// Supported accessibility guidelines:

packages/flutter_test/lib/src/mock_canvas.dart

@@ -12,6 +12,10 @@ import 'finders.dart';
 import 'recording_canvas.dart';
 import 'test_async_utils.dart';
 
+// Examples can assume:
+// late RenderObject myRenderObject;
+// late Symbol methodName;
+
 /// Matches objects or functions that paint a display list that matches the
 /// canvas calls described by the pattern.
 ///
@@ -20,8 +24,8 @@ import 'test_async_utils.dart';
 /// following signatures:
 ///
 /// ```dart
-/// void function(PaintingContext context, Offset offset);
-/// void function(Canvas canvas);
+/// void exampleOne(PaintingContext context, Offset offset) { }
+/// void exampleTwo(Canvas canvas) { }
 /// ```
 ///
 /// In the case of functions that take a [PaintingContext] and an [Offset], the
@@ -65,7 +69,9 @@ Matcher paintsExactlyCountTimes(Symbol methodName, int count) {
 /// literal syntax, for example:
 ///
 /// ```dart
-/// if (methodName == #drawCircle) { ... }
+/// if (methodName == #drawCircle) {
+///   // ...
+/// }
 /// ```
 typedef PaintPatternPredicate = bool Function(Symbol methodName, List<dynamic> arguments);
 

packages/flutter_test/lib/src/nonconst.dart

@@ -8,15 +8,15 @@
 /// ```dart
 /// class A {
 ///   const A(this.i);
-///   int i;
+///   final int? i;
 /// }
 ///
-/// main () {
+/// void main () {
 ///   // prevent prefer_const_constructors lint
 ///   A(nonconst(null));
 ///
 ///   // prevent prefer_const_declarations lint
-///   final int $null = nonconst(null);
+///   final int? $null = nonconst(null);
 ///   final A a = nonconst(const A(null));
 /// }
 /// ```

packages/flutter_test/lib/src/recording_canvas.dart

@@ -35,6 +35,9 @@ class RecordedInvocation {
   }
 }
 
+// Examples can assume:
+// late WidgetTester tester;
+
 /// A [Canvas] for tests that records its method calls.
 ///
 /// This class can be used in conjunction with [TestRecordingPaintingContext]

packages/flutter_test/lib/src/test_async_utils.dart

@@ -12,6 +12,9 @@ class _AsyncScope {
   final Zone zone;
 }
 
+// Examples can assume:
+// late WidgetTester tester;
+
 /// Utility class for all the async APIs in the `flutter_test` library.
 ///
 /// This class provides checking for asynchronous APIs, allowing the library to

packages/flutter_test/lib/src/widget_tester.dart

@@ -81,6 +81,9 @@ E? _lastWhereOrNull<E>(Iterable<E> list, bool Function(E) test) {
   return null;
 }
 
+// Examples can assume:
+// typedef MyWidget = Placeholder;
+
 /// Runs the [callback] inside the Flutter test environment.
 ///
 /// Use this function for testing custom [StatelessWidget]s and
@@ -117,7 +120,7 @@ E? _lastWhereOrNull<E>(Iterable<E> list, bool Function(E) test) {
 ///
 /// ```dart
 /// testWidgets('MyWidget', (WidgetTester tester) async {
-///   await tester.pumpWidget(MyWidget());
+///   await tester.pumpWidget(const MyWidget());
 ///   await tester.tap(find.text('Save'));
 ///   expect(find.text('Success'), findsOneWidget);
 /// });
@@ -319,12 +322,13 @@ class TargetPlatformVariant extends TestVariant<TargetPlatform> {
 /// }
 ///
 /// final ValueVariant<TestScenario> variants = ValueVariant<TestScenario>(
-///   <TestScenario>{value1, value2},
+///   <TestScenario>{TestScenario.value1, TestScenario.value2},
 /// );
-///
-/// testWidgets('Test handling of TestScenario', (WidgetTester tester) {
-///   expect(variants.currentValue, equals(value1));
-/// }, variant: variants);
+/// void main() {
+///   testWidgets('Test handling of TestScenario', (WidgetTester tester) async {
+///     expect(variants.currentValue, equals(TestScenario.value1));
+///   }, variant: variants);
+/// }
 /// ```
 /// {@end-tool}
 class ValueVariant<T> extends TestVariant<T> {
@@ -507,7 +511,7 @@ Future<void> expectLater(
 ///
 /// ```dart
 /// testWidgets('MyWidget', (WidgetTester tester) async {
-///   await tester.pumpWidget(MyWidget());
+///   await tester.pumpWidget(const MyWidget());
 ///   await tester.tap(find.text('Save'));
 ///   await tester.pump(); // allow the application to handle
 ///   await tester.pump(const Duration(seconds: 1)); // skip past the animation
@@ -555,7 +559,7 @@ class WidgetTester extends WidgetController implements HitTestDispatcher, Ticker
   /// {@tool snippet}
   /// ```dart
   /// testWidgets('MyWidget asserts invalid bounds', (WidgetTester tester) async {
-  ///   await tester.pumpWidget(MyWidget(-1));
+  ///   await tester.pumpWidget(const MyWidget());
   ///   expect(tester.takeException(), isAssertionError); // or isNull, as appropriate.
   /// });
   /// ```

packages/flutter_test/lib/src/window.dart

@@ -1173,7 +1173,7 @@ class _UnsupportedDisplay implements TestDisplay {
 ///   // Fake the desired properties of the TestWindow. All code running
 ///   // within this test will perceive the following fake text scale
 ///   // factor as the real text scale factor of the window.
-///   testBinding.window.textScaleFactorFakeValue = 2.5;
+///   testBinding.window.textScaleFactorTestValue = 2.5; // ignore: deprecated_member_use
 ///
 ///   // Test code that depends on text scale factor here.
 /// });