flutter create . on plugins also regenerates files for platforms supported in pubspec.yaml (#60159)

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

@@ -41,7 +41,7 @@ const List<String> _kAvailablePlatforms = <String>[
       ];
 
 const String _kNoPlatformsErrorMessage = '''
-The plugin project was generated without specifying the `--platforms` flag, no platforms are currently supported.
+The plugin project was generated without specifying the `--platforms` flag, no new platforms are added.
 To add platforms, run `flutter create -t plugin --platforms <platforms> .` under the same
 directory. You can also find detailed instructions on how to add platforms in the `pubspec.yaml` at https://flutter.dev/docs/development/packages-and-plugins/developing-packages#plugin-platforms.
 ''';
@@ -562,8 +562,20 @@ To edit platform code in an IDE see https://flutter.dev/developing-packages/#edi
       templateContext['windows'] = false;
       globals.printError(_kNoPlatformsErrorMessage);
     }
-    final List<String> platforms = _getSupportedPlatformsFromTemplateContext(templateContext);
-    final bool willAddPlatforms = platforms.isNotEmpty;
+    final List<String> platformsToAdd = _getSupportedPlatformsFromTemplateContext(templateContext);
+
+    final String pubspecPath = globals.fs.path.join(directory.absolute.path, 'pubspec.yaml');
+    final FlutterManifest manifest = FlutterManifest.createFromPath(pubspecPath, fileSystem: globals.fs, logger: globals.logger);
+    List<String> existingPlatforms = <String>[];
+    if (manifest.supportedPlatforms != null) {
+      existingPlatforms = manifest.supportedPlatforms.keys.toList();
+      for (final String existingPlatform in existingPlatforms) {
+        // re-generate files for existing platforms
+        templateContext[existingPlatform] = true;
+      }
+    }
+
+    final bool willAddPlatforms = platformsToAdd.isNotEmpty;
     templateContext['no_platforms'] = !willAddPlatforms;
     int generatedCount = 0;
     final String description = argResults.wasParsed('description')
@@ -583,10 +595,6 @@ To edit platform code in an IDE see https://flutter.dev/developing-packages/#edi
     if (willAddPlatforms) {
       // If adding new platforms to an existing plugin project, prints
       // a help message containing the platforms maps need to be added to the `platforms` key in the pubspec.
-      final String pubspecPath = globals.fs.path.join(directory.absolute.path, 'pubspec.yaml');
-      final List<String> platformsToAdd = List<String>.from(platforms);
-      final FlutterManifest manifest = FlutterManifest.createFromPath(pubspecPath, fileSystem: globals.fs, logger: globals.logger);
-      final List<String> existingPlatforms = manifest.supportedPlatforms.keys.toList();
       platformsToAdd.removeWhere(existingPlatforms.contains);
       final YamlMap platformsMapToPrint = Plugin.createPlatformsYamlMap(platformsToAdd, templateContext['pluginClass'] as String, templateContext['androidIdentifier'] as String);
       if (platformsMapToPrint.isNotEmpty) {

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

@@ -1820,6 +1820,131 @@ void main() {
       , throwsToolExit(message: 'The "--platforms" argument is not supported', exitCode: 2));
   });
 
+  testUsingContext('create a plugin with android, delete then re-create folders', () async {
+    Cache.flutterRoot = '../..';
+    when(mockFlutterVersion.frameworkRevision).thenReturn(frameworkRevision);
+    when(mockFlutterVersion.channel).thenReturn(frameworkChannel);
+
+    final CreateCommand command = CreateCommand();
+    final CommandRunner<void> runner = createTestCommandRunner(command);
+    await runner.run(<String>['create', '--no-pub', '--template=plugin', '--platforms=android', projectDir.path]);
+    expect(projectDir.childDirectory('android').existsSync(), true);
+    expect(projectDir.childDirectory('example').childDirectory('android').existsSync(), true);
+
+    globals.fs.file(globals.fs.path.join(projectDir.path, 'android')).deleteSync(recursive: true);
+    globals.fs.file(globals.fs.path.join(projectDir.path, 'example/android')).deleteSync(recursive: true);
+    expect(projectDir.childDirectory('android').existsSync(), false);
+    expect(projectDir.childDirectory('example').childDirectory('android').existsSync(), false);
+
+    await runner.run(<String>['create', '--no-pub', projectDir.path]);
+
+    expect(projectDir.childDirectory('android').existsSync(), true);
+    expect(projectDir.childDirectory('example').childDirectory('android').existsSync(), true);
+  });
+
+  testUsingContext('create a plugin with android, delete then re-create folders while also adding windows', () async {
+    Cache.flutterRoot = '../..';
+    when(mockFlutterVersion.frameworkRevision).thenReturn(frameworkRevision);
+    when(mockFlutterVersion.channel).thenReturn(frameworkChannel);
+
+    final CreateCommand command = CreateCommand();
+    final CommandRunner<void> runner = createTestCommandRunner(command);
+    await runner.run(<String>['create', '--no-pub', '--template=plugin', '--platforms=android', projectDir.path]);
+    expect(projectDir.childDirectory('android').existsSync(), true);
+    expect(projectDir.childDirectory('example').childDirectory('android').existsSync(), true);
+
+    globals.fs.file(globals.fs.path.join(projectDir.path, 'android')).deleteSync(recursive: true);
+    globals.fs.file(globals.fs.path.join(projectDir.path, 'example/android')).deleteSync(recursive: true);
+    expect(projectDir.childDirectory('android').existsSync(), false);
+    expect(projectDir.childDirectory('example').childDirectory('android').existsSync(), false);
+
+    await runner.run(<String>['create', '--no-pub', '--template=plugin', '--platforms=windows', projectDir.path]);
+
+    expect(projectDir.childDirectory('android').existsSync(), true);
+    expect(projectDir.childDirectory('example').childDirectory('android').existsSync(), true);
+    expect(projectDir.childDirectory('windows').existsSync(), true);
+    expect(projectDir.childDirectory('example').childDirectory('windows').existsSync(), true);
+  }, overrides: <Type, Generator>{
+    FeatureFlags: () => TestFeatureFlags(isWindowsEnabled: true),
+  });
+
+  testUsingContext('flutter create . on and existing plugin does not add android folders if android is not supported in pubspec', () async {
+    Cache.flutterRoot = '../..';
+    when(mockFlutterVersion.frameworkRevision).thenReturn(frameworkRevision);
+    when(mockFlutterVersion.channel).thenReturn(frameworkChannel);
+
+    final CreateCommand command = CreateCommand();
+    final CommandRunner<void> runner = createTestCommandRunner(command);
+    await runner.run(<String>['create', '--no-pub', '--template=plugin', '--platforms=ios', projectDir.path]);
+
+    await runner.run(<String>['create', '--no-pub', projectDir.path]);
+    expect(projectDir.childDirectory('android').existsSync(), false);
+    expect(projectDir.childDirectory('example').childDirectory('android').existsSync(), false);
+  });
+
+  testUsingContext('flutter create . on and existing plugin does not add windows folder even feature is enabled', () async {
+    Cache.flutterRoot = '../..';
+    when(mockFlutterVersion.frameworkRevision).thenReturn(frameworkRevision);
+    when(mockFlutterVersion.channel).thenReturn(frameworkChannel);
+
+    final CreateCommand command = CreateCommand();
+    final CommandRunner<void> runner = createTestCommandRunner(command);
+    await runner.run(<String>['create', '--no-pub', '--template=plugin', '--platforms=android', projectDir.path]);
+
+    await runner.run(<String>['create', '--no-pub', projectDir.path]);
+    expect(projectDir.childDirectory('windows').existsSync(), false);
+    expect(projectDir.childDirectory('example').childDirectory('windows').existsSync(), false);
+  }, overrides: <Type, Generator>{
+    FeatureFlags: () => TestFeatureFlags(isWindowsEnabled: true),
+  });
+
+  testUsingContext('flutter create . on and existing plugin does not add linux folder even feature is enabled', () async {
+    Cache.flutterRoot = '../..';
+    when(mockFlutterVersion.frameworkRevision).thenReturn(frameworkRevision);
+    when(mockFlutterVersion.channel).thenReturn(frameworkChannel);
+
+    final CreateCommand command = CreateCommand();
+    final CommandRunner<void> runner = createTestCommandRunner(command);
+    await runner.run(<String>['create', '--no-pub', '--template=plugin', '--platforms=android', projectDir.path]);
+
+    await runner.run(<String>['create', '--no-pub', projectDir.path]);
+    expect(projectDir.childDirectory('linux').existsSync(), false);
+    expect(projectDir.childDirectory('example').childDirectory('linux').existsSync(), false);
+  }, overrides: <Type, Generator>{
+    FeatureFlags: () => TestFeatureFlags(isLinuxEnabled: true),
+  });
+
+  testUsingContext('flutter create . on and existing plugin does not add web files even feature is enabled', () async {
+    Cache.flutterRoot = '../..';
+    when(mockFlutterVersion.frameworkRevision).thenReturn(frameworkRevision);
+    when(mockFlutterVersion.channel).thenReturn(frameworkChannel);
+
+    final CreateCommand command = CreateCommand();
+    final CommandRunner<void> runner = createTestCommandRunner(command);
+    await runner.run(<String>['create', '--no-pub', '--template=plugin', '--platforms=android', projectDir.path]);
+
+    await runner.run(<String>['create', '--no-pub', projectDir.path]);
+    expect(projectDir.childDirectory('lib').childFile('flutter_project_web.dart').existsSync(), false);
+  }, overrides: <Type, Generator>{
+    FeatureFlags: () => TestFeatureFlags(isWebEnabled: true),
+  });
+
+  testUsingContext('flutter create . on and existing plugin does not add macos folder even feature is enabled', () async {
+    Cache.flutterRoot = '../..';
+    when(mockFlutterVersion.frameworkRevision).thenReturn(frameworkRevision);
+    when(mockFlutterVersion.channel).thenReturn(frameworkChannel);
+
+    final CreateCommand command = CreateCommand();
+    final CommandRunner<void> runner = createTestCommandRunner(command);
+    await runner.run(<String>['create', '--no-pub', '--template=plugin', '--platforms=android', projectDir.path]);
+
+    await runner.run(<String>['create', '--no-pub', projectDir.path]);
+    expect(projectDir.childDirectory('macos').existsSync(), false);
+    expect(projectDir.childDirectory('example').childDirectory('macos').existsSync(), false);
+  }, overrides: <Type, Generator>{
+    FeatureFlags: () => TestFeatureFlags(isMacOSEnabled: true),
+  });
+
 }
 
 Future<void> _createProject(