[material_ui, cupertino_ui, go_router] Command to test dart fixes

.ci/targets/dart_unit_tests.yaml

@@ -11,3 +11,6 @@ tasks:
   - name: Dart unit tests - pathified
     script: .ci/scripts/dart_unit_tests_pathified.sh
     args: ["--platform=vm"]
+  - name: Dart fix tests
+    script: .ci/scripts/tool_runner.sh
+    args: ["test-dart-fixes"]

script/tool/lib/src/common/repository_package.dart

@@ -74,6 +74,9 @@ class RepositoryPackage {
   /// The test directory containing the package's Dart tests.
   Directory get testDirectory => directory.childDirectory('test');
 
+  /// The test directory containing the tests for the package's dart fixes.
+  Directory get dartFixTestDirectory => directory.childDirectory('test_fixes');
+
   /// The path to the script that is run by the `custom-test` command.
   File get customTestScript => directory.childDirectory('tool').childFile('run_tests.dart');
 

script/tool/lib/src/main.dart

@@ -30,6 +30,7 @@ import 'podspec_check_command.dart';
 import 'publish_check_command.dart';
 import 'publish_command.dart';
 import 'remove_dev_dependencies_command.dart';
+import 'test_dart_fixes_command.dart';
 import 'update_dependency_command.dart';
 import 'update_excerpts_command.dart';
 import 'update_min_sdk_command.dart';
@@ -75,6 +76,7 @@ void main(List<String> args) {
         ..addCommand(PublishCheckCommand(packagesDir))
         ..addCommand(PublishCommand(packagesDir))
         ..addCommand(RemoveDevDependenciesCommand(packagesDir))
+        ..addCommand(TestDartFixesCommand(packagesDir))
         ..addCommand(UpdateDependencyCommand(packagesDir))
         ..addCommand(UpdateExcerptsCommand(packagesDir))
         ..addCommand(UpdateMinSdkCommand(packagesDir))

script/tool/lib/src/test_dart_fixes_command.dart

@@ -0,0 +1,146 @@
+// Copyright 2013 The Flutter Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+
+import 'package:file/file.dart';
+import 'package:meta/meta.dart';
+
+import 'common/file_filters.dart';
+import 'common/package_looping_command.dart';
+import 'common/pub_utils.dart';
+import 'common/repository_package.dart';
+
+/// A command to run dart fix tests for packages that have a test_fixes
+/// directory.
+class TestDartFixesCommand extends PackageLoopingCommand {
+  /// Creates an instance of the test dart fixes command.
+  TestDartFixesCommand(super.packagesDir, {super.processRunner, super.platform, super.gitDir});
+
+  /// A map of the test directory used for each package passed to runForPackage.
+  @visibleForTesting
+  final testDirectories = <String, Directory>{};
+
+  @override
+  final String name = 'test-dart-fixes';
+
+  @override
+  List<String> get aliases => <String>[];
+
+  @override
+  final String description =
+      'Runs the Dart fix tests for all packages.\n\n'
+      'This command requires "flutter" to be in your path.';
+
+  @override
+  PackageLoopingType get packageLoopingType => PackageLoopingType.topLevelOnly;
+
+  @override
+  bool shouldIgnoreFile(String path) {
+    return isRepoLevelNonCodeImpactingFile(path) ||
+        isNativeCodeFile(path) ||
+        isPackageSupportFile(path);
+  }
+
+  @override
+  Future<PackageResult> runForPackage(RepositoryPackage package) async {
+    // Only run for packages that have a fix_tests directory.
+    if (!package.dartFixTestDirectory.existsSync()) {
+      return PackageResult.skip('No ${package.dartFixTestDirectory} directory.');
+    }
+
+    final Directory testDirectory;
+    try {
+      testDirectory = await _createTestDirectory(package);
+    } catch (error) {
+      return PackageResult.fail(['Failed to create temporary test directory: $error']);
+    }
+
+    PackageResult result;
+    try {
+      final bool success = await _runDartFixTests(testDirectory);
+      if (!success) {
+        throw Exception('Failed to run dart fix tests.');
+      }
+      result = PackageResult.success();
+    } catch (error) {
+      result = PackageResult.fail(['Dart fix tests failed: $error']);
+    }
+    if (testDirectory.existsSync()) {
+      await testDirectory.delete(recursive: true);
+    }
+    testDirectories[package.displayName] = testDirectory;
+    return result;
+  }
+
+  /// Create and prepare a temporary directory in which to run the dart fix
+  /// tests.
+  ///
+  /// It is the responsibility of the caller to delete this directory and its
+  /// contents when done.
+  static Future<Directory> _createTestDirectory(RepositoryPackage package) async {
+    final FileSystem fileSystem = package.directory.fileSystem;
+    final Directory testDirectory = await fileSystem.systemTempDirectory.createTemp();
+
+    // Copy from `test_fixes/` to the temp directory.
+    for (final FileSystemEntity entity in package.dartFixTestDirectory.listSync(recursive: true)) {
+      final String relativePath = fileSystem.path.relative(
+        entity.path,
+        from: package.dartFixTestDirectory.path,
+      );
+      final String destPath = fileSystem.path.join(testDirectory.path, relativePath);
+      if (entity is Directory) {
+        fileSystem.directory(destPath).createSync(recursive: true);
+      } else if (entity is File) {
+        fileSystem.file(destPath).parent.createSync(recursive: true);
+        entity.copySync(destPath);
+      }
+    }
+
+    // The pubspec.yaml file to create.
+    final File targetPubspecFile = fileSystem.file(
+      fileSystem.path.join(testDirectory.path, 'pubspec.yaml'),
+    );
+
+    final targetYaml =
+        '''
+name: test_fixes
+publish_to: "none"
+version: 1.0.0
+
+environment:
+  sdk: ">=2.18.0 <4.0.0"
+  flutter: ">=3.3.0"
+
+dependencies:
+  flutter:
+    sdk: flutter
+  ${package.directory.basename}:
+    path: ${package.directory.path}
+''';
+
+    await targetPubspecFile.writeAsString(targetYaml);
+    return testDirectory;
+  }
+
+  /// Run the dart fix tests for the package in the given temporary directory.
+  ///
+  /// Resolves with the status code of the command.
+  Future<bool> _runDartFixTests(Directory testDirectory) async {
+    // Run flutter pub get in the temp directory to set it up.
+    final bool success = await runPubGet(RepositoryPackage(testDirectory), processRunner, platform);
+
+    if (!success) {
+      return success;
+    }
+
+    // Run dart fix --compare-to-golden in the temp directory.
+    final int exitCode = await processRunner.runAndStream('dart', <String>[
+      'fix',
+      '--compare-to-golden',
+    ], workingDir: testDirectory);
+
+    return exitCode == 0;
+  }
+}