Migrate desktop_device to null safety (#92055)

packages/flutter_tools/lib/src/bundle_builder.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'package:meta/meta.dart';
 import 'package:pool/pool.dart';
 
@@ -29,15 +27,15 @@ class BundleBuilder {
   /// The default `mainPath` is `lib/main.dart`.
   /// The default  `manifestPath` is `pubspec.yaml`
   Future<void> build({
-    @required TargetPlatform platform,
-    @required BuildInfo buildInfo,
-    FlutterProject project,
-    String mainPath,
+    required TargetPlatform platform,
+    required BuildInfo buildInfo,
+    FlutterProject? project,
+    String? mainPath,
     String manifestPath = defaultManifestPath,
-    String applicationKernelFilePath,
-    String depfilePath,
-    String assetDirPath,
-    @visibleForTesting BuildSystem buildSystem
+    String? applicationKernelFilePath,
+    String? depfilePath,
+    String? assetDirPath,
+    @visibleForTesting BuildSystem? buildSystem,
   }) async {
     project ??= FlutterProject.current();
     mainPath ??= defaultMainPath;
@@ -52,7 +50,7 @@ class BundleBuilder {
       buildDir: project.dartTool.childDirectory('flutter_build'),
       cacheDir: globals.cache.getRoot(),
       flutterRootDir: globals.fs.directory(Cache.flutterRoot),
-      engineVersion: globals.artifacts.isLocalEngine
+      engineVersion: globals.artifacts!.isLocalEngine
           ? null
           : globals.flutterVersion.engineRevision,
       defines: <String, String>{
@@ -62,7 +60,7 @@ class BundleBuilder {
         kDeferredComponents: 'false',
         ...buildInfo.toBuildSystemEnvironment(),
       },
-      artifacts: globals.artifacts,
+      artifacts: globals.artifacts!,
       fileSystem: globals.fs,
       logger: globals.logger,
       processManager: globals.processManager,
@@ -72,7 +70,7 @@ class BundleBuilder {
     final Target target = buildInfo.mode == BuildMode.debug
         ? const CopyFlutterBundle()
         : const ReleaseCopyFlutterBundle();
-    final BuildResult result = await buildSystem.build(target, environment);
+    final BuildResult result = await buildSystem!.build(target, environment);
 
     if (!result.success) {
       for (final ExceptionMeasurement measurement in result.exceptions.values) {
@@ -108,14 +106,14 @@ class BundleBuilder {
   }
 }
 
-Future<AssetBundle> buildAssets({
-  String manifestPath,
-  String assetDirPath,
-  @required String packagesPath,
-  TargetPlatform targetPlatform,
+Future<AssetBundle?> buildAssets({
+  required String manifestPath,
+  String? assetDirPath,
+  String? packagesPath,
+  TargetPlatform? targetPlatform,
 }) async {
   assetDirPath ??= getAssetBuildDirectory();
-  packagesPath ??= globals.fs.path.absolute(packagesPath);
+  packagesPath ??= globals.fs.path.absolute('.packages');
 
   // Build the asset bundle.
   final AssetBundle assetBundle = AssetBundleFactory.instance.createBundle();
@@ -135,7 +133,7 @@ Future<AssetBundle> buildAssets({
 Future<void> writeBundle(
   Directory bundleDir,
   Map<String, DevFSContent> assetEntries,
-  { Logger loggerOverride }
+  { Logger? loggerOverride }
 ) async {
   loggerOverride ??= globals.logger;
   if (bundleDir.existsSync()) {

packages/flutter_tools/lib/src/desktop_device.dart

@@ -2,11 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'dart:async';
 
-import 'package:meta/meta.dart';
 import 'package:process/process.dart';
 
 import 'application_package.dart';
@@ -26,12 +23,12 @@ import 'protocol_discovery.dart';
 /// from, containing implementations that are common to all desktop devices.
 abstract class DesktopDevice extends Device {
   DesktopDevice(String identifier, {
-      @required PlatformType platformType,
-      @required bool ephemeral,
-      @required Logger logger,
-      @required ProcessManager processManager,
-      @required FileSystem fileSystem,
-      @required OperatingSystemUtils operatingSystemUtils,
+      required PlatformType platformType,
+      required bool ephemeral,
+      required Logger logger,
+      required ProcessManager processManager,
+      required FileSystem fileSystem,
+      required OperatingSystemUtils operatingSystemUtils,
     }) : _logger = logger,
          _processManager = processManager,
          _fileSystem = fileSystem,
@@ -60,7 +57,7 @@ abstract class DesktopDevice extends Device {
   @override
   Future<bool> isAppInstalled(
     ApplicationPackage app, {
-    String userIdentifier,
+    String? userIdentifier,
   }) async => true;
 
   // Since the host and target devices are the same, no work needs to be done
@@ -73,7 +70,7 @@ abstract class DesktopDevice extends Device {
   @override
   Future<bool> installApp(
     ApplicationPackage app, {
-    String userIdentifier,
+    String? userIdentifier,
   }) async => true;
 
   // Since the host and target devices are the same, no work needs to be done
@@ -81,14 +78,14 @@ abstract class DesktopDevice extends Device {
   @override
   Future<bool> uninstallApp(
     ApplicationPackage app, {
-    String userIdentifier,
+    String? userIdentifier,
   }) async => true;
 
   @override
   Future<bool> get isLocalEmulator async => false;
 
   @override
-  Future<String> get emulatorId async => null;
+  Future<String?> get emulatorId async => null;
 
   @override
   DevicePortForwarder get portForwarder => const NoOpDevicePortForwarder();
@@ -101,7 +98,7 @@ abstract class DesktopDevice extends Device {
 
   @override
   DeviceLogReader getLogReader({
-    ApplicationPackage app,
+    ApplicationPackage? app,
     bool includePastLogs = false,
   }) {
     assert(!includePastLogs, 'Past log reading not supported on desktop.');
@@ -114,13 +111,13 @@ abstract class DesktopDevice extends Device {
   @override
   Future<LaunchResult> startApp(
     ApplicationPackage package, {
-    String mainPath,
-    String route,
-    @required DebuggingOptions debuggingOptions,
+    String? mainPath,
+    String? route,
+    required DebuggingOptions debuggingOptions,
     Map<String, dynamic> platformArgs = const <String, dynamic>{},
     bool prebuiltApplication = false,
     bool ipv6 = false,
-    String userIdentifier,
+    String? userIdentifier,
   }) async {
     if (!prebuiltApplication) {
       await buildForDevice(
@@ -131,9 +128,9 @@ abstract class DesktopDevice extends Device {
     }
 
     // Ensure that the executable is locatable.
-    final BuildMode buildMode = debuggingOptions?.buildInfo?.mode;
-    final bool traceStartup = platformArgs['trace-startup'] as bool ?? false;
-    final String executable = executablePathForDevice(package, buildMode);
+    final BuildMode buildMode = debuggingOptions.buildInfo.mode;
+    final bool traceStartup = platformArgs['trace-startup'] as bool? ?? false;
+    final String? executable = executablePathForDevice(package, buildMode);
     if (executable == null) {
       _logger.printError('Unable to find executable to run');
       return LaunchResult.failed();
@@ -142,7 +139,7 @@ abstract class DesktopDevice extends Device {
     Process process;
     final List<String> command = <String>[
       executable,
-      ...?debuggingOptions?.dartEntrypointArgs,
+      ...debuggingOptions.dartEntrypointArgs,
     ];
     try {
       process = await _processManager.start(
@@ -157,17 +154,17 @@ abstract class DesktopDevice extends Device {
     unawaited(process.exitCode.then((_) => _runningProcesses.remove(process)));
 
     _deviceLogReader.initializeProcess(process);
-    if (debuggingOptions?.buildInfo?.isRelease == true) {
+    if (debuggingOptions.buildInfo.isRelease == true) {
       return LaunchResult.succeeded();
     }
     final ProtocolDiscovery observatoryDiscovery = ProtocolDiscovery.observatory(_deviceLogReader,
-      devicePort: debuggingOptions?.deviceVmServicePort,
-      hostPort: debuggingOptions?.hostVmServicePort,
+      devicePort: debuggingOptions.deviceVmServicePort,
+      hostPort: debuggingOptions.hostVmServicePort,
       ipv6: ipv6,
       logger: _logger,
     );
     try {
-      final Uri observatoryUri = await observatoryDiscovery.uri;
+      final Uri? observatoryUri = await observatoryDiscovery.uri;
       if (observatoryUri != null) {
         onAttached(package, buildMode, process);
         return LaunchResult.succeeded(observatoryUri: observatoryUri);
@@ -187,7 +184,7 @@ abstract class DesktopDevice extends Device {
   @override
   Future<bool> stopApp(
     ApplicationPackage app, {
-    String userIdentifier,
+    String? userIdentifier,
   }) async {
     bool succeeded = true;
     // Walk a copy of _runningProcesses, since the exit handler removes from the
@@ -200,19 +197,19 @@ abstract class DesktopDevice extends Device {
 
   @override
   Future<void> dispose() async {
-    await portForwarder?.dispose();
+    await portForwarder.dispose();
   }
 
   /// Builds the current project for this device, with the given options.
   Future<void> buildForDevice(
     ApplicationPackage package, {
-    String mainPath,
+    String? mainPath,
     BuildInfo buildInfo,
   });
 
   /// Returns the path to the executable to run for [package] on this device for
   /// the given [buildMode].
-  String executablePathForDevice(ApplicationPackage package, BuildMode buildMode);
+  String? executablePathForDevice(ApplicationPackage package, BuildMode buildMode);
 
   /// Called after a process is attached, allowing any device-specific extra
   /// steps to be run.
@@ -225,7 +222,7 @@ abstract class DesktopDevice extends Device {
   /// The format of the environment variables is:
   ///   * FLUTTER_ENGINE_SWITCHES to the number of switches.
   ///   * FLUTTER_ENGINE_SWITCH_<N> (indexing from 1) to the individual switches.
-  Map<String, String> _computeEnvironment(DebuggingOptions debuggingOptions, bool traceStartup, String route) {
+  Map<String, String> _computeEnvironment(DebuggingOptions debuggingOptions, bool traceStartup, String? route) {
     int flags = 0;
     final Map<String, String> environment = <String, String>{};
 

packages/flutter_tools/lib/src/preview_device.dart

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'dart:async';
 
 import 'package:meta/meta.dart';
@@ -37,10 +35,10 @@ BundleBuilder _defaultBundleBuilder() {
 /// device is not currently discoverable.
 class PreviewDevice extends Device {
   PreviewDevice({
-    @required Platform platform,
-    @required ProcessManager processManager,
-    @required Logger logger,
-    @required FileSystem fileSystem,
+    required Platform platform,
+    required ProcessManager processManager,
+    required Logger logger,
+    required FileSystem fileSystem,
     @visibleForTesting BundleBuilderFactory builderFactory = _defaultBundleBuilder,
   }) : _platform = platform,
        _processManager = processManager,
@@ -62,18 +60,18 @@ class PreviewDevice extends Device {
   Future<void> dispose() async { }
 
   @override
-  Future<String> get emulatorId async => null;
+  Future<String?> get emulatorId async => null;
 
   final DesktopLogReader _logReader = DesktopLogReader();
 
   @override
-  FutureOr<DeviceLogReader> getLogReader({covariant ApplicationPackage app, bool includePastLogs = false}) => _logReader;
+  FutureOr<DeviceLogReader> getLogReader({covariant ApplicationPackage? app, bool includePastLogs = false}) => _logReader;
 
   @override
-  Future<bool> installApp(covariant ApplicationPackage app, {String userIdentifier}) async => true;
+  Future<bool> installApp(covariant ApplicationPackage? app, {String? userIdentifier}) async => true;
 
   @override
-  Future<bool> isAppInstalled(covariant ApplicationPackage app, {String userIdentifier}) async => false;
+  Future<bool> isAppInstalled(covariant ApplicationPackage app, {String? userIdentifier}) async => false;
 
   @override
   Future<bool> isLatestBuildInstalled(covariant ApplicationPackage app) async => false;
@@ -96,24 +94,23 @@ class PreviewDevice extends Device {
   @override
   Future<String> get sdkNameAndVersion async => 'preview';
 
-  Process _process;
-  Directory _assetDirectory;
+  Process? _process;
 
   @override
   Future<LaunchResult> startApp(covariant ApplicationPackage package, {
-    String mainPath,
-    String route,
-    @required DebuggingOptions debuggingOptions,
-    Map<String, dynamic> platformArgs,
+    String? mainPath,
+    String? route,
+    required DebuggingOptions debuggingOptions,
+    Map<String, dynamic> platformArgs = const <String, dynamic>{},
     bool prebuiltApplication = false,
     bool ipv6 = false,
-    String userIdentifier,
+    String? userIdentifier,
   }) async {
-    _assetDirectory = _fileSystem.systemTempDirectory
+    final Directory assetDirectory = _fileSystem.systemTempDirectory
       .createTempSync('flutter_preview.');
 
     // Build assets and perform initial compilation.
-    Status status;
+    Status? status;
     try {
       status = _logger.startProgress('Compiling application for preview...');
       await _bundleBuilderFactory().build(
@@ -124,32 +121,32 @@ class PreviewDevice extends Device {
       );
       copyDirectory(_fileSystem.directory(
         getAssetBuildDirectory()),
-        _assetDirectory.childDirectory('data').childDirectory('flutter_assets'),
+        assetDirectory.childDirectory('data').childDirectory('flutter_assets'),
       );
     } finally {
-      status.stop();
+      status?.stop();
     }
 
     // Merge with precompiled executable.
-    final Directory precompiledDirectory = _fileSystem.directory(_fileSystem.path.join(Cache.flutterRoot, 'artifacts_temp', 'Debug'));
-    copyDirectory(precompiledDirectory, _assetDirectory);
+    final Directory precompiledDirectory = _fileSystem.directory(_fileSystem.path.join(Cache.flutterRoot!, 'artifacts_temp', 'Debug'));
+    copyDirectory(precompiledDirectory, assetDirectory);
 
     final Process process = await _processManager.start(
       <String>[
-        _assetDirectory.childFile('splash').path,
+        assetDirectory.childFile('splash').path,
       ],
     );
     _process = process;
     _logReader.initializeProcess(process);
 
     final ProtocolDiscovery observatoryDiscovery = ProtocolDiscovery.observatory(_logReader,
-      devicePort: debuggingOptions?.deviceVmServicePort,
-      hostPort: debuggingOptions?.hostVmServicePort,
+      devicePort: debuggingOptions.deviceVmServicePort,
+      hostPort: debuggingOptions.hostVmServicePort,
       ipv6: ipv6,
       logger: _logger,
     );
     try {
-      final Uri observatoryUri = await observatoryDiscovery.uri;
+      final Uri? observatoryUri = await observatoryDiscovery.uri;
       if (observatoryUri != null) {
         return LaunchResult.succeeded(observatoryUri: observatoryUri);
       }
@@ -166,8 +163,8 @@ class PreviewDevice extends Device {
   }
 
   @override
-  Future<bool> stopApp(covariant ApplicationPackage app, {String userIdentifier}) async {
-    return _process?.kill();
+  Future<bool> stopApp(covariant ApplicationPackage app, {String? userIdentifier}) async {
+    return _process?.kill() == true;
   }
 
   @override
@@ -179,7 +176,7 @@ class PreviewDevice extends Device {
   }
 
   @override
-  Future<bool> uninstallApp(covariant ApplicationPackage app, {String userIdentifier}) async {
+  Future<bool> uninstallApp(covariant ApplicationPackage app, {String? userIdentifier}) async {
     return true;
   }
 

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

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
-
 import 'dart:async';
 
 import 'package:file/memory.dart';
@@ -18,7 +16,6 @@ import 'package:flutter_tools/src/device.dart';
 import 'package:flutter_tools/src/device_port_forwarder.dart';
 import 'package:flutter_tools/src/project.dart';
 
-import 'package:meta/meta.dart';
 import 'package:test/fake.dart';
 
 import '../src/common.dart';
@@ -50,8 +47,8 @@ void main() {
     testWithoutContext('Install checks always return true', () async {
       final FakeDesktopDevice device = setUpDesktopDevice();
 
-      expect(await device.isAppInstalled(null), true);
-      expect(await device.isLatestBuildInstalled(null), true);
+      expect(await device.isAppInstalled(FakeApplicationPackage()), true);
+      expect(await device.isLatestBuildInstalled(FakeApplicationPackage()), true);
       expect(device.category, Category.desktop);
     });
 
@@ -89,7 +86,7 @@ void main() {
         ),
       ]);
       final FakeDesktopDevice device = setUpDesktopDevice(processManager: processManager, fileSystem: fileSystem);
-      final String executableName = device.executablePathForDevice(null, BuildMode.debug);
+      final String? executableName = device.executablePathForDevice(FakeApplicationPackage(), BuildMode.debug);
       fileSystem.file(executableName).writeAsStringSync('\n');
       final FakeApplicationPackage package = FakeApplicationPackage();
       final LaunchResult result = await device.startApp(
@@ -248,7 +245,7 @@ void main() {
   testWithoutContext('createDevFSWriter returns a LocalDevFSWriter', () {
     final FakeDesktopDevice device = setUpDesktopDevice();
 
-    expect(device.createDevFSWriter(null, ''), isA<LocalDevFSWriter>());
+    expect(device.createDevFSWriter(FakeApplicationPackage(), ''), isA<LocalDevFSWriter>());
   });
 
   testWithoutContext('startApp supports dartEntrypointArgs', () async {
@@ -308,10 +305,10 @@ void main() {
 }
 
 FakeDesktopDevice setUpDesktopDevice({
-  FileSystem fileSystem,
-  Logger logger,
-  ProcessManager processManager,
-  OperatingSystemUtils operatingSystemUtils,
+  FileSystem? fileSystem,
+  Logger? logger,
+  ProcessManager? processManager,
+  OperatingSystemUtils? operatingSystemUtils,
   bool nullExecutablePathForDevice = false,
 }) {
   return FakeDesktopDevice(
@@ -326,11 +323,11 @@ FakeDesktopDevice setUpDesktopDevice({
 /// A trivial subclass of DesktopDevice for testing the shared functionality.
 class FakeDesktopDevice extends DesktopDevice {
   FakeDesktopDevice({
-    @required ProcessManager processManager,
-    @required Logger logger,
-    @required FileSystem fileSystem,
-    @required OperatingSystemUtils operatingSystemUtils,
-    this.nullExecutablePathForDevice,
+    required ProcessManager processManager,
+    required Logger logger,
+    required FileSystem fileSystem,
+    required OperatingSystemUtils operatingSystemUtils,
+    this.nullExecutablePathForDevice = false,
   }) : super(
       'dummy',
       platformType: PlatformType.linux,
@@ -342,10 +339,10 @@ class FakeDesktopDevice extends DesktopDevice {
   );
 
   /// The [mainPath] last passed to [buildForDevice].
-  String lastBuiltMainPath;
+  String? lastBuiltMainPath;
 
   /// The [buildInfo] last passed to [buildForDevice].
-  BuildInfo lastBuildInfo;
+  BuildInfo? lastBuildInfo;
 
   final bool nullExecutablePathForDevice;
 
@@ -364,8 +361,8 @@ class FakeDesktopDevice extends DesktopDevice {
   @override
   Future<void> buildForDevice(
     ApplicationPackage package, {
-    String mainPath,
-    BuildInfo buildInfo,
+    String? mainPath,
+    BuildInfo? buildInfo,
   }) async {
     lastBuiltMainPath = mainPath;
     lastBuildInfo = buildInfo;
@@ -373,7 +370,7 @@ class FakeDesktopDevice extends DesktopDevice {
 
   // Dummy implementation that just returns the build mode name.
   @override
-  String executablePathForDevice(ApplicationPackage package, BuildMode buildMode) {
+  String? executablePathForDevice(ApplicationPackage package, BuildMode buildMode) {
     if (nullExecutablePathForDevice) {
       return null;
     }