Remove patching of package_config.json from Flutter Pub wrapper. (#169306)

This PR removes the mechanics around `generateSyntheticPackage` from
Flutter's `pub` wrapper (`DefaultPub`).

The feature it supported (`package:flutter_gen`) was deprecated (opt-in
3.29, opt-out 3.32) and is now being removed:


https://docs.flutter.dev/release/breaking-changes/flutter-generate-i10n-source

---

One integration test (`flutter_gen_test.dart`) will fail at this PR
until it is deleted in (pending)
flutter/flutter#169283.

/cc @sigurdm yay!

Author: matanlurey

packages/flutter_tools/lib/src/dart/pub.dart

@@ -22,7 +22,6 @@ import '../base/process.dart';
 import '../cache.dart';
 import '../convert.dart';
 import '../dart/package_map.dart';
-import '../features.dart';
 import '../project.dart';
 import '../version.dart';
 
@@ -192,7 +191,6 @@ abstract class Pub {
     required PubContext context,
     required String command,
     bool touchesPackageConfig = false,
-    bool generateSyntheticPackage = false,
     PubOutputMode outputMode = PubOutputMode.all,
   });
 }
@@ -242,8 +240,6 @@ class _DefaultPub implements Pub {
     required FlutterProject project,
     bool upgrade = false,
     bool offline = false,
-    bool generateSyntheticPackage = false,
-    bool generateSyntheticPackageForExample = false,
     String? flutterRootOverride,
     bool checkUpToDate = false,
     bool shouldSkipThirdPartyGenerator = true,
@@ -700,15 +696,6 @@ class _DefaultPub implements Pub {
   ///
   /// Creates a corresponding `package_config_subset` file that is used by the
   /// build system to avoid rebuilds caused by an updated pub timestamp.
-  ///
-  /// if `project.generateSyntheticPackage` is `true` then insert flutter_gen
-  /// synthetic package into the package configuration. This is used by the l10n
-  /// localization tooling to insert a new reference into the package_config
-  /// file, allowing the import of a package URI that is not specified in the
-  /// pubspec.yaml
-  ///
-  /// For more information, see:
-  ///   * [generateLocalizations]
   Future<void> _updatePackageConfig(FlutterProject project, File packageConfigFile) async {
     final PackageConfig packageConfig = await loadPackageConfigWithLogging(
       packageConfigFile,
@@ -718,47 +705,6 @@ class _DefaultPub implements Pub {
     packageConfigFile.parent
         .childFile('package_config_subset')
         .writeAsStringSync(_computePackageConfigSubset(packageConfig, _fileSystem));
-
-    // If we aren't generating localizations, short-circuit.
-    if (!project.manifest.generateLocalizations) {
-      return;
-    }
-
-    // Workaround for https://github.com/flutter/flutter/issues/164864.
-    // If this flag is set, synthetic packages cannot be used, so we short-circut.
-    if (featureFlags.isExplicitPackageDependenciesEnabled) {
-      return;
-    }
-
-    if (!_fileSystem.path.equals(packageConfigFile.parent.parent.path, project.directory.path)) {
-      throwToolExit(
-        '`generate: true` is not supported within workspaces unless flutter config '
-        '--explicit-package-dependencies is set.',
-      );
-    }
-
-    if (packageConfig.packages.any((Package package) => package.name == 'flutter_gen')) {
-      return;
-    }
-
-    // TODO(jonahwillams): Using raw json manipulation here because
-    // savePackageConfig always writes to local io, and it changes absolute
-    // paths to relative on round trip.
-    // See: https://github.com/dart-lang/package_config/issues/99,
-    // and: https://github.com/dart-lang/package_config/issues/100.
-
-    // Because [loadPackageConfigWithLogging] succeeded [packageConfigFile]
-    // we can rely on the file to exist and be correctly formatted.
-    final Map<String, dynamic> jsonContents =
-        json.decode(packageConfigFile.readAsStringSync()) as Map<String, dynamic>;
-
-    (jsonContents['packages'] as List<dynamic>).add(<String, dynamic>{
-      'name': 'flutter_gen',
-      'rootUri': 'flutter_gen',
-      'languageVersion': '2.12',
-    });
-
-    packageConfigFile.writeAsStringSync(json.encode(jsonContents));
   }
 
   // Subset the package config file to only the parts that are relevant for

packages/flutter_tools/test/general.shard/dart/pub_get_test.dart

@@ -12,7 +12,6 @@ import 'package:flutter_tools/src/base/platform.dart';
 import 'package:flutter_tools/src/cache.dart';
 import 'package:flutter_tools/src/convert.dart';
 import 'package:flutter_tools/src/dart/pub.dart';
-import 'package:flutter_tools/src/features.dart';
 import 'package:flutter_tools/src/project.dart';
 
 import '../../src/common.dart';
@@ -988,133 +987,30 @@ exit code: 66
     expect(processManager, hasNoRemainingExpectations);
   });
 
-  testUsingContext(
-    'package_config_subset file is generated from packages and not timestamp',
-    () async {
-      final FileSystem fileSystem = MemoryFileSystem.test();
-      final Pub pub = Pub.test(
-        fileSystem: fileSystem,
-        logger: BufferLogger.test(),
-        processManager: FakeProcessManager.any(),
-        botDetector: const FakeBotDetector(false),
-        stdio: FakeStdio(),
-        platform: FakePlatform(
-          environment: const <String, String>{'PUB_CACHE': 'custom/pub-cache/path'},
-        ),
-      );
-      fileSystem.file('version').createSync();
-      fileSystem.file('pubspec.yaml')
-        ..createSync()
-        ..writeAsStringSync('''
-      flutter:
-        generate: true
-      ''');
-      fileSystem.file('.dart_tool/package_config.json')
-        ..createSync(recursive: true)
-        ..writeAsStringSync('''
-      {"configVersion": 2,"packages": [
-        {
-          "name": "flutter_tools",
-          "rootUri": "../",
-          "packageUri": "lib/",
-          "languageVersion": "2.7"
-        }
-      ],"generated":"some-time"}
-''');
-
-      await pub.get(
-        project: FlutterProject.fromDirectoryTest(fileSystem.currentDirectory),
-        context: PubContext.flutterTests,
-      );
-
-      expect(
-        fileSystem.file('.dart_tool/package_config_subset').readAsStringSync(),
-        'flutter_tools\n'
-        '2.7\n'
-        'file:///\n'
-        'file:///lib/\n'
-        '2\n',
-      );
-    },
-    overrides: <Type, Generator>{
-      // ignore: avoid_redundant_argument_values
-      FeatureFlags: () => TestFeatureFlags(isExplicitPackageDependenciesEnabled: false),
-    },
-  );
-
-  testUsingContext(
-    'cannot use `generate: true` with a workspace without --explicit-package-dependencies',
-    () async {
-      final FileSystem fileSystem = MemoryFileSystem.test();
-      final Pub pub = Pub.test(
-        fileSystem: fileSystem,
-        logger: BufferLogger.test(),
-        processManager: FakeProcessManager.any(),
-        botDetector: const FakeBotDetector(false),
-        stdio: FakeStdio(),
-        platform: FakePlatform(
-          environment: const <String, String>{'PUB_CACHE': 'custom/pub-cache/path'},
-        ),
-      );
-
-      final Directory pkg = fileSystem.directory('workspace_pkg')..createSync(recursive: true);
-      fileSystem.file('version').createSync();
-      pkg.childFile('pubspec.yaml')
-        ..createSync()
-        ..writeAsStringSync('''
-      flutter:
-        generate: true
-      ''');
-      fileSystem.file('.dart_tool/package_config.json')
-        ..createSync(recursive: true)
-        ..writeAsStringSync('''
-      {"configVersion": 2,"packages": [
-        {
-          "name": "flutter_tools",
-          "rootUri": "../",
-          "packageUri": "lib/",
-          "languageVersion": "2.7"
-        }
-      ],"generated":"some-time"}
-''');
-
-      await expectLater(
-        pub.get(project: FlutterProject.fromDirectoryTest(pkg), context: PubContext.flutterTests),
-        throwsToolExit(message: '`generate: true` is not supported within workspaces unless'),
-      );
-    },
-    overrides: <Type, Generator>{
-      // ignore: avoid_redundant_argument_values
-      FeatureFlags: () => TestFeatureFlags(isExplicitPackageDependenciesEnabled: false),
-    },
-  );
-
-  testUsingContext(
-    'can use `generate: true` with a workspace with --explicit-package-dependencies',
-    () async {
-      final FileSystem fileSystem = MemoryFileSystem.test();
-      final Pub pub = Pub.test(
-        fileSystem: fileSystem,
-        logger: BufferLogger.test(),
-        processManager: FakeProcessManager.any(),
-        botDetector: const FakeBotDetector(false),
-        stdio: FakeStdio(),
-        platform: FakePlatform(
-          environment: const <String, String>{'PUB_CACHE': 'custom/pub-cache/path'},
-        ),
-      );
+  testUsingContext('can use generate: true within a workspace', () async {
+    final FileSystem fileSystem = MemoryFileSystem.test();
+    final Pub pub = Pub.test(
+      fileSystem: fileSystem,
+      logger: BufferLogger.test(),
+      processManager: FakeProcessManager.any(),
+      botDetector: const FakeBotDetector(false),
+      stdio: FakeStdio(),
+      platform: FakePlatform(
+        environment: const <String, String>{'PUB_CACHE': 'custom/pub-cache/path'},
+      ),
+    );
 
-      final Directory pkg = fileSystem.directory('workspace_pkg')..createSync(recursive: true);
-      fileSystem.file('version').createSync();
-      pkg.childFile('pubspec.yaml')
-        ..createSync()
-        ..writeAsStringSync('''
+    final Directory pkg = fileSystem.directory('workspace_pkg')..createSync(recursive: true);
+    fileSystem.file('version').createSync();
+    pkg.childFile('pubspec.yaml')
+      ..createSync()
+      ..writeAsStringSync('''
       flutter:
         generate: true
       ''');
-      fileSystem.file('.dart_tool/package_config.json')
-        ..createSync(recursive: true)
-        ..writeAsStringSync('''
+    fileSystem.file('.dart_tool/package_config.json')
+      ..createSync(recursive: true)
+      ..writeAsStringSync('''
       {"configVersion": 2,"packages": [
         {
           "name": "flutter_tools",
@@ -1125,12 +1021,11 @@ exit code: 66
       ],"generated":"some-time"}
 ''');
 
-      await expectLater(
-        pub.get(project: FlutterProject.fromDirectoryTest(pkg), context: PubContext.flutterTests),
-        completes,
-      );
-    },
-  );
+    await expectLater(
+      pub.get(project: FlutterProject.fromDirectoryTest(pkg), context: PubContext.flutterTests),
+      completes,
+    );
+  });
 
   testWithoutContext('Pub error handling', () async {
     final BufferLogger logger = BufferLogger.test();