Finish removing --explicit-package-dependencies. (flutter#169950)

Closes flutter#48918.
Closes flutter#102983.

Author: matanlurey

dev/benchmarks/test_apps/stocks/l10n.yaml

@@ -14,7 +14,6 @@ output-localization-file: stock_strings.dart
 ## `template-arb-file` describes the template arb file that the tool
 ## will use to check and validate the remaining arb files when
 ## generating Flutter's localization files.
-synthetic-package: false
 template-arb-file: stocks_en.arb
 ## setting `nullable-getter` to false generates a non-nullable
 ## StockStrings getter. This removes the need for adding null checks

packages/flutter_tools/lib/src/commands/generate_localizations.dart

@@ -8,7 +8,6 @@ import '../artifacts.dart';
 import '../base/common.dart';
 import '../base/file_system.dart';
 import '../base/logger.dart';
-import '../features.dart';
 import '../localizations/gen_l10n.dart';
 import '../localizations/localizations_utils.dart';
 import '../runner/flutter_command.dart';
@@ -36,16 +35,16 @@ class GenerateLocalizationsCommand extends FlutterCommand {
     argParser.addOption(
       'output-dir',
       help:
-          'The directory where the generated localization classes will be written '
-          'if the synthetic-package flag is set to false.\n'
-          '\n'
-          'If output-dir is specified and the synthetic-package flag is enabled, '
-          'this option will be ignored by the tool.\n'
+          'The directory where the generated localization classes will be written.'
           '\n'
           'The app must import the file specified in the "--output-localization-file" '
           'option from this directory. If unspecified, this defaults to the same '
           'directory as the input directory specified in "--arb-dir".',
     );
+    argParser.addFlag(
+      'synthetic-package',
+      help: 'DEPRECATED. This flag cannot be enabled and should be removed.',
+    );
     argParser.addOption(
       'template-arb-file',
       help:
@@ -149,19 +148,6 @@ class GenerateLocalizationsCommand extends FlutterCommand {
           '\n'
           'When null, the JSON file will not be generated.',
     );
-    argParser.addFlag(
-      'synthetic-package',
-      defaultsTo: !featureFlags.isExplicitPackageDependenciesEnabled,
-      help:
-          'Determines whether or not the generated output files will be '
-          'generated as a synthetic package or at a specified directory in '
-          'the Flutter project.\n'
-          '\n'
-          'DEPRECATED: https://flutter.dev/to/flutter-gen-deprecation.\n'
-          '\n'
-          'When synthetic-package is set to false, it will generate the '
-          'localizations files in the directory specified by arb-dir by default.\n',
-    );
     argParser.addOption(
       'project-dir',
       valueHelp: 'absolute/path/to/flutter/project',

packages/flutter_tools/lib/src/features.dart

@@ -53,9 +53,6 @@ abstract class FeatureFlags {
   /// Whether Swift Package Manager dependency management is enabled.
   bool get isSwiftPackageManagerEnabled => false;
 
-  /// Whether explicit package dependency management is enabled.
-  bool get isExplicitPackageDependenciesEnabled => false;
-
   /// Whether a particular feature is enabled for the current channel.
   ///
   /// Prefer using one of the specific getters above instead of this API.

packages/flutter_tools/lib/src/flutter_features.dart

@@ -51,14 +51,6 @@ mixin FlutterFeatureFlagsIsEnabled implements FeatureFlags {
 
   @override
   bool get isSwiftPackageManagerEnabled => isEnabled(swiftPackageManager);
-
-  // TODO(matanlurey): Remove this when the flag is no longer in use.
-  //
-  // Setting this always to true prevents `false` from ever being returned in
-  // production code, but still allows tests to override it so that they can be
-  // migrated (or deleted) one at a time instead of a single large PR.
-  @override
-  bool get isExplicitPackageDependenciesEnabled => true;
 }
 
 interface class FlutterFeatureFlags extends FeatureFlags with FlutterFeatureFlagsIsEnabled {

packages/flutter_tools/lib/src/flutter_plugins.dart

@@ -130,8 +130,7 @@ Future<List<Plugin>> findPlugins(FlutterProject project, {bool throwOnError = tr
       packageName,
       dependency.rootUri,
       project.manifest.dependencies,
-      isDevDependency:
-          featureFlags.isExplicitPackageDependenciesEnabled && dependency.isExclusiveDevDependency,
+      isDevDependency: dependency.isExclusiveDevDependency,
       fileSystem: fs,
     );
     if (plugin != null) {
@@ -1160,8 +1159,7 @@ void _createPlatformPluginSymlinks(
 ///
 /// Assumes `pub get` has been executed since last change to `pubspec.yaml`.
 ///
-/// If [FeatureFlags.isExplicitPackageDependenciesEnabled] is `true`,
-/// plugins that are development-only dependencies might be labeled or,
+/// Plugins that are development-only dependencies might be labeled or,
 /// depending on the platform, omitted from metadata or platform-specific artifacts.
 Future<void> refreshPluginsList(
   FlutterProject project, {

packages/flutter_tools/lib/src/localizations/localizations_utils.dart

@@ -8,6 +8,7 @@ import 'package:yaml/yaml.dart';
 import '../base/common.dart';
 import '../base/file_system.dart';
 import '../base/logger.dart';
+import '../globals.dart' as globals;
 import '../runner/flutter_command.dart';
 import 'gen_l10n_types.dart';
 import 'language_subtag_registry.dart';
@@ -487,6 +488,22 @@ LocalizationOptions parseLocalizationsOptionsFromYAML({
     logger.printError('Expected ${file.path} to contain a map, instead was $yamlNode');
     throw Exception();
   }
+  const String kSyntheticPackage = 'synthetic-package';
+  const String kFlutterGenNotice = 'http://flutter.dev/to/flutter-gen-deprecation';
+  final bool? syntheticPackage = _tryReadBool(yamlNode, kSyntheticPackage, logger);
+  if (syntheticPackage != null) {
+    if (syntheticPackage) {
+      throwToolExit(
+        '${file.path}: Cannot enable "$kSyntheticPackage", this feature has '
+        'been removed. See $kFlutterGenNotice.',
+      );
+    } else {
+      logger.printWarning(
+        '${file.path}: The argument "$kSyntheticPackage" no longer has any '
+        'effect and should be removed. See $kFlutterGenNotice',
+      );
+    }
+  }
   return LocalizationOptions(
     arbDir: _tryReadFilePath(yamlNode, 'arb-dir', logger, fileSystem) ?? defaultArbDir,
     outputDir: _tryReadFilePath(yamlNode, 'output-dir', logger, fileSystem),
@@ -523,6 +540,21 @@ LocalizationOptions parseLocalizationsOptionsFromCommand({
   required FlutterCommand command,
   required String defaultArbDir,
 }) {
+  const String kSyntheticPackage = 'synthetic-package';
+  const String kFlutterGenNotice = 'http://flutter.dev/to/flutter-gen-deprecation';
+  if (command.argResults!.wasParsed(kSyntheticPackage)) {
+    if (command.boolArg(kSyntheticPackage)) {
+      throwToolExit(
+        'Cannot enable "$kSyntheticPackage", this feature has been removed. '
+        'See $kFlutterGenNotice.',
+      );
+    } else {
+      globals.logger.printWarning(
+        'The argument "$kSyntheticPackage" no longer has any effect and should '
+        'be removed. See $kFlutterGenNotice',
+      );
+    }
+  }
   return LocalizationOptions(
     arbDir: command.stringArg('arb-dir') ?? defaultArbDir,
     outputDir: command.stringArg('output-dir'),

packages/flutter_tools/lib/src/runner/flutter_command.dart

@@ -1888,9 +1888,7 @@ abstract class FlutterCommand extends Command<void> {
     if (!shouldRunPub) {
       return;
     }
-    await project.regeneratePlatformSpecificTooling(
-      releaseMode: featureFlags.isExplicitPackageDependenciesEnabled && releaseMode,
-    );
+    await project.regeneratePlatformSpecificTooling(releaseMode: releaseMode);
   }
 
   /// The set of development artifacts required for this command.

packages/flutter_tools/test/commands.shard/hermetic/generate_localizations_test.dart

@@ -69,76 +69,6 @@ void main() {
     },
   );
 
-  testUsingContext(
-    'not using synthetic packages (explicitly)',
-    () async {
-      final Directory l10nDirectory = fileSystem.directory(fileSystem.path.join('lib', 'l10n'));
-      final File arbFile = l10nDirectory.childFile('app_en.arb')..createSync(recursive: true);
-
-      arbFile.writeAsStringSync('''
-{
-  "helloWorld": "Hello, World!",
-  "@helloWorld": {
-    "description": "Sample description"
-  }
-}''');
-      fileSystem.file('pubspec.yaml').writeAsStringSync('''
-flutter:
-  generate: true''');
-
-      final GenerateLocalizationsCommand command = GenerateLocalizationsCommand(
-        fileSystem: fileSystem,
-        logger: logger,
-        artifacts: artifacts,
-        processManager: processManager,
-      );
-      await createTestCommandRunner(command).run(<String>['gen-l10n', '--no-synthetic-package']);
-
-      expect(l10nDirectory.existsSync(), true);
-      expect(l10nDirectory.childFile('app_localizations_en.dart').existsSync(), true);
-      expect(l10nDirectory.childFile('app_localizations.dart').existsSync(), true);
-    },
-    overrides: <Type, Generator>{
-      FileSystem: () => fileSystem,
-      ProcessManager: () => FakeProcessManager.any(),
-    },
-  );
-
-  testUsingContext(
-    'not using synthetic packages (due to --explicit-package-dependencies)',
-    () async {
-      final Directory l10nDirectory = fileSystem.directory(fileSystem.path.join('lib', 'l10n'));
-      final File arbFile = l10nDirectory.childFile('app_en.arb')..createSync(recursive: true);
-
-      arbFile.writeAsStringSync('''
-{
-  "helloWorld": "Hello, World!",
-  "@helloWorld": {
-    "description": "Sample description"
-  }
-}''');
-      fileSystem.file('pubspec.yaml').writeAsStringSync('''
-flutter:
-  generate: true''');
-
-      final GenerateLocalizationsCommand command = GenerateLocalizationsCommand(
-        fileSystem: fileSystem,
-        logger: logger,
-        artifacts: artifacts,
-        processManager: processManager,
-      );
-      await createTestCommandRunner(command).run(<String>['gen-l10n']);
-
-      expect(l10nDirectory.existsSync(), true);
-      expect(l10nDirectory.childFile('app_localizations_en.dart').existsSync(), true);
-      expect(l10nDirectory.childFile('app_localizations.dart').existsSync(), true);
-    },
-    overrides: <Type, Generator>{
-      FileSystem: () => fileSystem,
-      ProcessManager: () => FakeProcessManager.any(),
-    },
-  );
-
   testUsingContext(
     'throws error when arguments are invalid',
     () async {
@@ -590,7 +520,7 @@ format: false
   );
 
   testUsingContext(
-    'throw when generate: false and uses synthetic package when run with l10n.yaml',
+    'throw when generate: false when run with l10n.yaml',
     () async {
       final File arbFile = fileSystem.file(fileSystem.path.join('lib', 'l10n', 'app_en.arb'))
         ..createSync(recursive: true);
@@ -636,7 +566,7 @@ format: false
   );
 
   testUsingContext(
-    'throw when generate: false and uses synthetic package when run via commandline options',
+    'throw when generate: false when run via commandline options',
     () async {
       final File arbFile = fileSystem.file(fileSystem.path.join('lib', 'l10n', 'app_en.arb'))
         ..createSync(recursive: true);
@@ -667,8 +597,7 @@ format: false
         processManager: processManager,
       );
       expect(
-        () async =>
-            createTestCommandRunner(command).run(<String>['gen-l10n', '--synthetic-package']),
+        () async => createTestCommandRunner(command).run(<String>['gen-l10n']),
         throwsToolExit(
           message:
               'Attempted to generate localizations code without having the flutter: generate flag turned on.',
@@ -689,13 +618,44 @@ format: false
       processManager: processManager,
     );
     expect(
-      () async => createTestCommandRunner(
-        command,
-      ).run(<String>['gen-l10n', '--synthetic-package', 'false']),
+      () async => createTestCommandRunner(command).run(<String>['gen-l10n', 'false']),
       throwsToolExit(message: 'Unexpected positional argument "false".'),
     );
   });
 
+  testUsingContext('throws error when synthetic-package is provided', () async {
+    final GenerateLocalizationsCommand command = GenerateLocalizationsCommand(
+      fileSystem: fileSystem,
+      logger: logger,
+      artifacts: artifacts,
+      processManager: processManager,
+    );
+    await expectLater(
+      () async => createTestCommandRunner(command).run(<String>['gen-l10n', '--synthetic-package']),
+      throwsToolExit(message: 'synthetic-package'),
+    );
+  });
+
+  testUsingContext(
+    'prints warning when --no-synthetic-package is provided',
+    () async {
+      final GenerateLocalizationsCommand command = GenerateLocalizationsCommand(
+        fileSystem: fileSystem,
+        logger: logger,
+        artifacts: artifacts,
+        processManager: processManager,
+      );
+      fileSystem
+          .file(fileSystem.path.join('lib', 'l10n', 'app_en.arb'))
+          .createSync(recursive: true);
+      final File pubspecFile = fileSystem.file('pubspec.yaml')..createSync();
+      pubspecFile.writeAsStringSync(BasicProjectWithFlutterGen().pubspec);
+      await createTestCommandRunner(command).run(<String>['gen-l10n', '--no-synthetic-package']);
+      expect(logger.warningText, contains('synthetic-package'));
+    },
+    overrides: <Type, Generator>{Logger: () => logger},
+  );
+
   group(AppResourceBundle, () {
     testWithoutContext("can be parsed without FormatException when it's content is empty", () {
       final File arbFile = fileSystem.file(fileSystem.path.join('lib', 'l10n', 'app_en.arb'))

packages/flutter_tools/test/commands.shard/permeable/packages_test.dart

@@ -387,7 +387,7 @@ workspace:
     );
 
     testUsingContext(
-      'get generates normal files when l10n.yaml has synthetic-package: false',
+      'get generates files into lib/l10n',
       () async {
         final String projectPath = await createProject(
           tempDir,
@@ -403,7 +403,7 @@ flutter:
   generate: true
 ''');
         projectDir.childFile('pubspec.yaml').writeAsStringSync(pubspecFileContent);
-        projectDir.childFile('l10n.yaml').writeAsStringSync('synthetic-package: false');
+        projectDir.childFile('l10n.yaml').createSync();
         await runCommandIn(projectPath, 'get');
         expect(
           projectDir