Implement dartPluginClass support for plugins (#74469)

dev/devicelab/bin/tasks/dart_plugin_registry_test.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 'package:flutter_devicelab/tasks/dart_plugin_registry_tests.dart';
+import 'package:flutter_devicelab/framework/framework.dart';
+
+Future<void> main() async {
+  await task(dartPluginRegistryTest());
+}

dev/devicelab/lib/tasks/dart_plugin_registry_tests.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:async';
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:path/path.dart' as path;
+import 'package:flutter_devicelab/framework/framework.dart';
+import 'package:flutter_devicelab/framework/task_result.dart';
+import 'package:flutter_devicelab/framework/utils.dart';
+
+TaskFunction dartPluginRegistryTest({
+  String deviceIdOverride,
+  Map<String, String> environment,
+}) {
+  final Directory tempDir = Directory.systemTemp
+      .createTempSync('flutter_devicelab_dart_plugin_test.');
+  return () async {
+    try {
+      section('Create implementation plugin');
+      await inDirectory(tempDir, () async {
+        await flutter(
+          'create',
+          options: <String>[
+            '--template=plugin',
+            '--org',
+            'io.flutter.devicelab',
+            '--platforms',
+            'macos',
+            'plugin_platform_implementation',
+          ],
+          environment: environment,
+        );
+      });
+
+      final File pluginMain = File(path.join(
+        tempDir.absolute.path,
+        'plugin_platform_implementation',
+        'lib',
+        'plugin_platform_implementation.dart',
+      ));
+      if (!pluginMain.existsSync()) {
+        return TaskResult.failure('${pluginMain.path} does not exist');
+      }
+
+      // Patch plugin main dart file.
+      await pluginMain.writeAsString('''
+class PluginPlatformInterfaceMacOS {
+  static void registerWith() {
+    print('PluginPlatformInterfaceMacOS.registerWith() was called');
+  }
+}
+''', flush: true);
+
+      // Patch plugin main pubspec file.
+      final File pluginImplPubspec = File(path.join(
+        tempDir.absolute.path,
+        'plugin_platform_implementation',
+        'pubspec.yaml',
+      ));
+      String pluginImplPubspecContent = await pluginImplPubspec.readAsString();
+      pluginImplPubspecContent = pluginImplPubspecContent.replaceFirst(
+        '        pluginClass: PluginPlatformImplementationPlugin',
+        '        pluginClass: PluginPlatformImplementationPlugin\n'
+            '        dartPluginClass: PluginPlatformInterfaceMacOS\n',
+      );
+      pluginImplPubspecContent = pluginImplPubspecContent.replaceFirst(
+          '    platforms:\n',
+          '    implements: plugin_platform_interface\n'
+              '    platforms:\n');
+      await pluginImplPubspec.writeAsString(pluginImplPubspecContent,
+          flush: true);
+
+      section('Create interface plugin');
+      await inDirectory(tempDir, () async {
+        await flutter(
+          'create',
+          options: <String>[
+            '--template=plugin',
+            '--org',
+            'io.flutter.devicelab',
+            '--platforms',
+            'macos',
+            'plugin_platform_interface',
+          ],
+          environment: environment,
+        );
+      });
+      final File pluginInterfacePubspec = File(path.join(
+        tempDir.absolute.path,
+        'plugin_platform_interface',
+        'pubspec.yaml',
+      ));
+      String pluginInterfacePubspecContent =
+          await pluginInterfacePubspec.readAsString();
+      pluginInterfacePubspecContent =
+          pluginInterfacePubspecContent.replaceFirst(
+              '        pluginClass: PluginPlatformInterfacePlugin',
+              '        default_package: plugin_platform_implementation\n');
+      pluginInterfacePubspecContent =
+          pluginInterfacePubspecContent.replaceFirst(
+              'dependencies:',
+              'dependencies:\n'
+                  '  plugin_platform_implementation:\n'
+                  '    path: ../plugin_platform_implementation\n');
+      await pluginInterfacePubspec.writeAsString(pluginInterfacePubspecContent,
+          flush: true);
+
+      section('Create app');
+
+      await inDirectory(tempDir, () async {
+        await flutter(
+          'create',
+          options: <String>[
+            '--template=app',
+            '--org',
+            'io.flutter.devicelab',
+            '--platforms',
+            'macos',
+            'app',
+          ],
+          environment: environment,
+        );
+      });
+
+      final File appPubspec = File(path.join(
+        tempDir.absolute.path,
+        'app',
+        'pubspec.yaml',
+      ));
+      String appPubspecContent = await appPubspec.readAsString();
+      appPubspecContent = appPubspecContent.replaceFirst(
+          'dependencies:',
+          'dependencies:\n'
+              '  plugin_platform_interface:\n'
+              '    path: ../plugin_platform_interface\n');
+      await appPubspec.writeAsString(appPubspecContent, flush: true);
+
+      section('Flutter run for macos');
+
+      await inDirectory(path.join(tempDir.path, 'app'), () async {
+        final Process run = await startProcess(
+          path.join(flutterDirectory.path, 'bin', 'flutter'),
+          flutterCommandArgs('run', <String>['-d', 'macos', '-v']),
+          environment: null,
+        );
+        Completer<void> registryExecutedCompleter = Completer<void>();
+        final StreamSubscription<void> subscription = run.stdout
+            .transform<String>(utf8.decoder)
+            .transform<String>(const LineSplitter())
+            .listen((String line) {
+          if (line.contains(
+              'PluginPlatformInterfaceMacOS.registerWith() was called')) {
+            registryExecutedCompleter.complete();
+          }
+          print('stdout: $line');
+        });
+
+        section('Wait for registry execution');
+        await registryExecutedCompleter.future
+            .timeout(const Duration(minutes: 1));
+
+        // Hot restart.
+        run.stdin.write('R');
+        registryExecutedCompleter = Completer<void>();
+
+        section('Wait for registry execution after hot restart');
+        await registryExecutedCompleter.future
+            .timeout(const Duration(minutes: 1));
+
+        subscription.cancel();
+        run.kill();
+      });
+      return TaskResult.success(null);
+    } finally {
+      rmTree(tempDir);
+    }
+  };
+}

packages/flutter_tools/lib/src/build_system/build_system.dart

@@ -308,6 +308,7 @@ class Environment {
     @required Artifacts artifacts,
     @required ProcessManager processManager,
     @required String engineVersion,
+    @required bool generateDartPluginRegistry,
     Directory buildDir,
     Map<String, String> defines = const <String, String>{},
     Map<String, String> inputs = const <String, String>{},
@@ -347,6 +348,7 @@ class Environment {
       processManager: processManager,
       engineVersion: engineVersion,
       inputs: inputs,
+      generateDartPluginRegistry: generateDartPluginRegistry,
     );
   }
 
@@ -363,6 +365,7 @@ class Environment {
     Map<String, String> defines = const <String, String>{},
     Map<String, String> inputs = const <String, String>{},
     String engineVersion,
+    bool generateDartPluginRegistry = false,
     @required FileSystem fileSystem,
     @required Logger logger,
     @required Artifacts artifacts,
@@ -381,6 +384,7 @@ class Environment {
       artifacts: artifacts,
       processManager: processManager,
       engineVersion: engineVersion,
+      generateDartPluginRegistry: generateDartPluginRegistry,
     );
   }
 
@@ -398,6 +402,7 @@ class Environment {
     @required this.artifacts,
     @required this.engineVersion,
     @required this.inputs,
+    @required this.generateDartPluginRegistry,
   });
 
   /// The [Source] value which is substituted with the path to [projectDir].
@@ -475,6 +480,11 @@ class Environment {
 
   /// The version of the current engine, or `null` if built with a local engine.
   final String engineVersion;
+
+  /// Whether to generate the Dart plugin registry.
+  /// When [true], the main entrypoint is wrapped and the wrapper becomes
+  /// the new entrypoint.
+  final bool generateDartPluginRegistry;
 }
 
 /// The result information from the build system.

packages/flutter_tools/lib/src/build_system/targets/common.dart

@@ -279,6 +279,8 @@ class KernelSnapshot extends Target {
       fileSystemScheme: fileSystemScheme,
       dartDefines: decodeDartDefines(environment.defines, kDartDefines),
       packageConfig: packageConfig,
+      buildDir: environment.buildDir,
+      generateDartPluginRegistry: environment.generateDartPluginRegistry,
     );
     if (output == null || output.errorCount != 0) {
       throw Exception();

packages/flutter_tools/lib/src/bundle.dart

@@ -160,6 +160,7 @@ Future<void> buildWithAssemble({
     fileSystem: globals.fs,
     logger: globals.logger,
     processManager: globals.processManager,
+    generateDartPluginRegistry: true,
   );
   final Target target = buildMode == BuildMode.debug
     ? const CopyFlutterBundle()

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

@@ -195,7 +195,8 @@ class AssembleCommand extends FlutterCommand {
       processManager: globals.processManager,
       engineVersion: globals.artifacts.isLocalEngine
         ? null
-        : globals.flutterVersion.engineRevision
+        : globals.flutterVersion.engineRevision,
+      generateDartPluginRegistry: true,
     );
     return result;
   }

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

@@ -385,6 +385,7 @@ end
           engineVersion: globals.artifacts.isLocalEngine
               ? null
               : globals.flutterVersion.engineRevision,
+          generateDartPluginRegistry: true,
         );
         Target target;
         // Always build debug for simulator.

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

@@ -119,6 +119,7 @@ class PackagesGetCommand extends FlutterCommand {
         outputDir: globals.fs.directory(getBuildDirectory()),
         processManager: globals.processManager,
         projectDir: flutterProject.directory,
+        generateDartPluginRegistry: true,
       );
 
       await generateLocalizationsSyntheticPackage(
@@ -324,6 +325,7 @@ class PackagesInteractiveGetCommand extends FlutterCommand {
         outputDir: globals.fs.directory(getBuildDirectory()),
         processManager: globals.processManager,
         projectDir: flutterProject.directory,
+        generateDartPluginRegistry: true,
       );
 
       await generateLocalizationsSyntheticPackage(

packages/flutter_tools/lib/src/compile.dart

@@ -19,6 +19,8 @@ import 'base/logger.dart';
 import 'base/platform.dart';
 import 'build_info.dart';
 import 'convert.dart';
+import 'plugins.dart';
+import 'project.dart';
 
 /// The target model describes the set of core libraries that are available within
 /// the SDK.
@@ -209,6 +211,8 @@ class KernelCompiler {
     String fileSystemScheme,
     String initializeFromDill,
     String platformDill,
+    Directory buildDir,
+    bool generateDartPluginRegistry = false,
     @required String packagesPath,
     @required BuildMode buildMode,
     @required bool trackWidgetCreation,
@@ -227,7 +231,8 @@ class KernelCompiler {
       throwToolExit('Unable to find Dart binary at $engineDartPath');
     }
     String mainUri;
-    final Uri mainFileUri = _fileSystem.file(mainPath).uri;
+    final File mainFile = _fileSystem.file(mainPath);
+    final Uri mainFileUri = mainFile.uri;
     if (packagesPath != null) {
       mainUri = packageConfig.toPackageUri(mainFileUri)?.toString();
     }
@@ -235,6 +240,21 @@ class KernelCompiler {
     if (outputFilePath != null && !_fileSystem.isFileSync(outputFilePath)) {
       _fileSystem.file(outputFilePath).createSync(recursive: true);
     }
+    if (buildDir != null && generateDartPluginRegistry) {
+      // `generated_main.dart` is under `.dart_tools/flutter_build/`,
+      // so the resident compiler can find it.
+      final File newMainDart = buildDir.parent.childFile('generated_main.dart');
+      if (await generateMainDartWithPluginRegistrant(
+        FlutterProject.current(),
+        packageConfig,
+        mainUri,
+        newMainDart,
+        mainFile,
+      )) {
+        mainUri = newMainDart.path;
+      }
+    }
+
     final List<String> command = <String>[
       engineDartPath,
       '--disable-dart-dev',
@@ -579,7 +599,6 @@ class DefaultResidentCompiler implements ResidentCompiler {
     if (!_controller.hasListener) {
       _controller.stream.listen(_handleCompilationRequest);
     }
-
     final Completer<CompilerOutput> completer = Completer<CompilerOutput>();
     _controller.add(
       _RecompileRequest(completer, mainUri, invalidatedFiles, outputPath, packageConfig, suppressErrors)

packages/flutter_tools/lib/src/devfs.dart

@@ -518,6 +518,20 @@ class DevFS {
     // dill files that depend on the invalidated files.
     _logger.printTrace('Compiling dart to kernel with ${invalidatedFiles.length} updated files');
 
+    // `generated_main.dart` contains the Dart plugin registry.
+    if (projectRootPath != null) {
+      final File generatedMainDart = _fileSystem.file(
+        _fileSystem.path.join(
+          projectRootPath,
+          '.dart_tool',
+          'flutter_build',
+          'generated_main.dart',
+        ),
+      );
+      if (generatedMainDart != null && generatedMainDart.existsSync()) {
+        mainUri = generatedMainDart.uri;
+      }
+    }
     // Await the compiler response after checking if the bundle is updated. This allows the file
     // stating to be done while waiting for the frontend_server response.
     final Future<CompilerOutput> pendingCompilerOutput = generator.recompile(

packages/flutter_tools/lib/src/flutter_manifest.dart

@@ -86,6 +86,13 @@ class FlutterManifest {
   /// The string value of the top-level `name` property in the `pubspec.yaml` file.
   String get appName => _descriptor['name'] as String ?? '';
 
+  /// Contains the name of the dependencies.
+  /// These are the keys specified in the `dependency` map.
+  Set<String> get dependencies {
+    final YamlMap dependencies = _descriptor['dependencies'] as YamlMap;
+    return dependencies != null ? <String>{...dependencies.keys.cast<String>()} : <String>{};
+  }
+
   // Flag to avoid printing multiple invalid version messages.
   bool _hasShowInvalidVersionMsg = false;
 

packages/flutter_tools/lib/src/platform_plugins.dart

@@ -16,6 +16,9 @@ const String kPluginClass = 'pluginClass';
 /// Constant for 'pluginClass' key in plugin maps.
 const String kDartPluginClass = 'dartPluginClass';
 
+// Constant for 'defaultPackage' key in plugin maps.
+const String kDefaultPackage = 'default_package';
+
 /// Marker interface for all platform specific plugin config implementations.
 abstract class PluginPlatform {
   const PluginPlatform();
@@ -207,6 +210,7 @@ class MacOSPlugin extends PluginPlatform implements NativeOrDartPlugin {
     @required this.name,
     this.pluginClass,
     this.dartPluginClass,
+    this.defaultPackage,
   });
 
   factory MacOSPlugin.fromYaml(String name, YamlMap yaml) {
@@ -220,6 +224,7 @@ class MacOSPlugin extends PluginPlatform implements NativeOrDartPlugin {
       name: name,
       pluginClass: pluginClass,
       dartPluginClass: yaml[kDartPluginClass] as String,
+      defaultPackage: yaml[kDefaultPackage] as String,
     );
   }
 
@@ -227,7 +232,9 @@ class MacOSPlugin extends PluginPlatform implements NativeOrDartPlugin {
     if (yaml == null) {
       return false;
     }
-    return yaml[kPluginClass] is String || yaml[kDartPluginClass] is String;
+    return yaml[kPluginClass] is String ||
+           yaml[kDartPluginClass] is String ||
+           yaml[kDefaultPackage] is String;
   }
 
   static const String kConfigKey = 'macos';
@@ -235,6 +242,7 @@ class MacOSPlugin extends PluginPlatform implements NativeOrDartPlugin {
   final String name;
   final String pluginClass;
   final String dartPluginClass;
+  final String defaultPackage;
 
   @override
   bool isNative() => pluginClass != null;
@@ -244,7 +252,8 @@ class MacOSPlugin extends PluginPlatform implements NativeOrDartPlugin {
     return <String, dynamic>{
       'name': name,
       if (pluginClass != null) 'class': pluginClass,
-      if (dartPluginClass != null) 'dartPluginClass': dartPluginClass,
+      if (dartPluginClass != null) kDartPluginClass : dartPluginClass,
+      if (defaultPackage != null) kDefaultPackage : defaultPackage,
     };
   }
 }
@@ -258,7 +267,8 @@ class WindowsPlugin extends PluginPlatform implements NativeOrDartPlugin{
     @required this.name,
     this.pluginClass,
     this.dartPluginClass,
-  }) : assert(pluginClass != null || dartPluginClass != null);
+    this.defaultPackage,
+  }) : assert(pluginClass != null || dartPluginClass != null || defaultPackage != null);
 
   factory WindowsPlugin.fromYaml(String name, YamlMap yaml) {
     assert(validate(yaml));
@@ -271,6 +281,7 @@ class WindowsPlugin extends PluginPlatform implements NativeOrDartPlugin{
       name: name,
       pluginClass: pluginClass,
       dartPluginClass: yaml[kDartPluginClass] as String,
+      defaultPackage: yaml[kDefaultPackage] as String,
     );
   }
 
@@ -278,7 +289,9 @@ class WindowsPlugin extends PluginPlatform implements NativeOrDartPlugin{
     if (yaml == null) {
       return false;
     }
-    return yaml[kDartPluginClass] is String || yaml[kPluginClass] is String;
+    return yaml[kPluginClass] is String ||
+           yaml[kDartPluginClass] is String ||
+           yaml[kDefaultPackage] is String;
   }
 
   static const String kConfigKey = 'windows';
@@ -286,6 +299,7 @@ class WindowsPlugin extends PluginPlatform implements NativeOrDartPlugin{
   final String name;
   final String pluginClass;
   final String dartPluginClass;
+  final String defaultPackage;
 
   @override
   bool isNative() => pluginClass != null;
@@ -296,7 +310,8 @@ class WindowsPlugin extends PluginPlatform implements NativeOrDartPlugin{
       'name': name,
       if (pluginClass != null) 'class': pluginClass,
       if (pluginClass != null) 'filename': _filenameForCppClass(pluginClass),
-      if (dartPluginClass != null) 'dartPluginClass': dartPluginClass,
+      if (dartPluginClass != null) kDartPluginClass: dartPluginClass,
+      if (defaultPackage != null) kDefaultPackage: defaultPackage,
     };
   }
 }
@@ -310,7 +325,8 @@ class LinuxPlugin extends PluginPlatform implements NativeOrDartPlugin {
     @required this.name,
     this.pluginClass,
     this.dartPluginClass,
-  }) : assert(pluginClass != null || dartPluginClass != null);
+    this.defaultPackage,
+  }) : assert(pluginClass != null || dartPluginClass != null || defaultPackage != null);
 
   factory LinuxPlugin.fromYaml(String name, YamlMap yaml) {
     assert(validate(yaml));
@@ -323,6 +339,7 @@ class LinuxPlugin extends PluginPlatform implements NativeOrDartPlugin {
       name: name,
       pluginClass: pluginClass,
       dartPluginClass: yaml[kDartPluginClass] as String,
+      defaultPackage: yaml[kDefaultPackage] as String,
     );
   }
 
@@ -330,7 +347,9 @@ class LinuxPlugin extends PluginPlatform implements NativeOrDartPlugin {
     if (yaml == null) {
       return false;
     }
-    return yaml[kPluginClass] is String || yaml[kDartPluginClass] is String;
+    return yaml[kPluginClass] is String ||
+           yaml[kDartPluginClass] is String ||
+           yaml[kDefaultPackage] is String;
   }
 
   static const String kConfigKey = 'linux';
@@ -338,6 +357,7 @@ class LinuxPlugin extends PluginPlatform implements NativeOrDartPlugin {
   final String name;
   final String pluginClass;
   final String dartPluginClass;
+  final String defaultPackage;
 
   @override
   bool isNative() => pluginClass != null;
@@ -348,7 +368,8 @@ class LinuxPlugin extends PluginPlatform implements NativeOrDartPlugin {
       'name': name,
       if (pluginClass != null) 'class': pluginClass,
       if (pluginClass != null) 'filename': _filenameForCppClass(pluginClass),
-      if (dartPluginClass != null) 'dartPluginClass': dartPluginClass,
+      if (dartPluginClass != null) kDartPluginClass: dartPluginClass,
+      if (defaultPackage != null) kDefaultPackage: defaultPackage,
     };
   }
 }

packages/flutter_tools/lib/src/resident_runner.dart

@@ -920,6 +920,7 @@ abstract class ResidentRunner {
       outputDir: globals.fs.directory(getBuildDirectory()),
       processManager: globals.processManager,
       projectDir: globals.fs.currentDirectory,
+      generateDartPluginRegistry: true,
     );
     _lastBuild = await globals.buildSystem.buildIncremental(
       const GenerateLocalizationsTarget(),

packages/flutter_tools/lib/src/run_hot.dart

@@ -26,6 +26,7 @@ import 'devfs.dart';
 import 'device.dart';
 import 'features.dart';
 import 'globals.dart' as globals;
+import 'project.dart';
 import 'reporting/reporting.dart';
 import 'resident_devtools_handler.dart';
 import 'resident_runner.dart';
@@ -314,6 +315,15 @@ class HotRunner extends ResidentRunner {
     bool enableDevTools = false,
     String route,
   }) async {
+    File mainFile = globals.fs.file(mainPath);
+    // `generated_main.dart` contains the Dart plugin registry.
+    final Directory buildDir = FlutterProject.current()
+        .directory
+        .childDirectory(globals.fs.path.join('.dart_tool', 'flutter_build'));
+    final File newMainDart = buildDir?.childFile('generated_main.dart');
+    if (newMainDart != null && newMainDart.existsSync()) {
+      mainFile = newMainDart;
+    }
     firstBuildTime = DateTime.now();
 
     final List<Future<bool>> startupTasks = <Future<bool>>[];
@@ -326,7 +336,7 @@ class HotRunner extends ResidentRunner {
       if (device.generator != null) {
         startupTasks.add(
           device.generator.recompile(
-            globals.fs.file(mainPath).uri,
+            mainFile.uri,
             <Uri>[],
             // When running without a provided applicationBinary, the tool will
             // simultaneously run the initial frontend_server compilation and

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

@@ -1153,6 +1153,7 @@ abstract class FlutterCommand extends Command<void> {
         outputDir: globals.fs.directory(getBuildDirectory()),
         processManager: globals.processManager,
         projectDir: project.directory,
+        generateDartPluginRegistry: true,
       );
 
       await generateLocalizationsSyntheticPackage(

packages/flutter_tools/lib/src/web/compile.dart

@@ -69,6 +69,8 @@ Future<void> buildWeb(
         ? null
         : globals.flutterVersion.engineRevision,
       flutterRootDir: globals.fs.directory(Cache.flutterRoot),
+      // Web uses a different Dart plugin registry.
+      generateDartPluginRegistry: false,
     ));
     if (!result.success) {
       for (final ExceptionMeasurement measurement in result.exceptions.values) {

packages/flutter_tools/test/general.shard/android/deferred_components_setup_validator_test.dart

@@ -36,6 +36,7 @@ void main() {
       logger: logger,
       processManager: globals.processManager,
       engineVersion: 'invalidEngineVersion',
+      generateDartPluginRegistry: false,
     );
     return result;
   }

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

@@ -220,6 +220,39 @@ void main() {
     );
 
     expect(plugin.platforms, <String, PluginPlatform>{});
+    expect(plugin.defaultPackagePlatforms, <String, String>{
+      'linux': 'sample_package_linux',
+      'macos': 'sample_package_macos',
+      'windows': 'sample_package_windows',
+    });
+    expect(plugin.pluginDartClassPlatforms, <String, String>{});
+  });
+
+  testWithoutContext('Desktop plugin parsing allows a dartPluginClass field', () {
+    final FileSystem fileSystem = MemoryFileSystem.test();
+    const String pluginYamlRaw =
+      'platforms:\n'
+      ' linux:\n'
+      '  dartPluginClass: LinuxClass\n'
+      ' macos:\n'
+      '  dartPluginClass: MacOSClass\n'
+      ' windows:\n'
+      '  dartPluginClass: WindowsClass\n';
+
+    final YamlMap pluginYaml = loadYaml(pluginYamlRaw) as YamlMap;
+    final Plugin plugin = Plugin.fromYaml(
+      _kTestPluginName,
+      _kTestPluginPath,
+      pluginYaml,
+      const <String>[],
+      fileSystem: fileSystem,
+    );
+
+    expect(plugin.pluginDartClassPlatforms, <String, String>{
+      'linux': 'LinuxClass',
+      'macos': 'MacOSClass',
+      'windows': 'WindowsClass',
+    });
   });
 
   testWithoutContext('Plugin parsing throws a fatal error on an empty plugin', () {

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

@@ -110,6 +110,17 @@ void main() {
         );
       });
 
+      _testInMemory('reads dependencies from pubspec.yaml', () async {
+        final Directory directory = globals.fs.directory('myproject');
+        directory.childFile('pubspec.yaml')
+          ..createSync(recursive: true)
+          ..writeAsStringSync(validPubspecWithDependencies);
+        expect(
+          FlutterProject.fromDirectory(directory).manifest.dependencies,
+          <String>{'plugin_a', 'plugin_b'},
+        );
+      });
+
       _testInMemory('sets up location', () async {
         final Directory directory = globals.fs.directory('myproject');
         expect(
@@ -905,6 +916,16 @@ name: hello
 flutter:
 ''';
 
+String get validPubspecWithDependencies => '''
+name: hello
+flutter:
+
+dependencies:
+  plugin_a:
+  plugin_b:
+''';
+
+
 String get invalidPubspec => '''
 name: hello
 flutter: