[flutter_tools] migrate some files to null safety (#110354)

packages/flutter_tools/lib/src/commands/drive.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.
 
-
-
 import 'dart:async';
 
 import 'package:meta/meta.dart';

packages/flutter_tools/lib/src/drive/drive_service.dart

@@ -290,9 +290,9 @@ class FlutterDriverService extends DriverService {
   }) async {
     if (writeSkslOnExit != null) {
       final FlutterView flutterView = (await _vmService.getFlutterViews()).first;
-      final Map<String, Object> result = await (_vmService.getSkSLs(
+      final Map<String, Object?>? result = await _vmService.getSkSLs(
         viewId: flutterView.id
-      ) as FutureOr<Map<String, Object>>);
+      );
       await sharedSkSlWriter(_device!, result, outputFile: writeSkslOnExit, logger: _logger);
     }
     // If the application package is available, stop and uninstall.

packages/flutter_tools/lib/src/resident_runner.dart

@@ -934,7 +934,7 @@ abstract class ResidentHandlers {
       viewId: views.first.id,
     );
     final Device device = flutterDevice.device!;
-    return sharedSkSlWriter(device, data!);
+    return sharedSkSlWriter(device, data);
   }
 
   /// Take a screenshot on the provided [device].

packages/flutter_tools/lib/src/sksl_writer.dart

@@ -13,12 +13,12 @@ import 'convert.dart';
 import 'device.dart';
 import 'globals.dart' as globals;
 
-Future<String?> sharedSkSlWriter(Device device, Map<String, Object?> data, {
+Future<String?> sharedSkSlWriter(Device device, Map<String, Object?>? data, {
   File? outputFile,
   Logger? logger,
 }) async {
   logger ??= globals.logger;
-  if (data.isEmpty) {
+  if (data == null || data.isEmpty) {
     logger.printStatus(
       'No data was received. To ensure SkSL data can be generated use a '
       'physical device then:\n'

packages/flutter_tools/lib/src/test/flutter_web_goldens.dart

@@ -56,7 +56,7 @@ class TestGoldenComparator {
   /// to reduce the overhead of starting `flutter_tester`.
   Future<TestGoldenComparatorProcess?> _processForTestFile(Uri testUri) async {
     if (testUri == _previousTestUri) {
-      return _previousComparator;
+      return _previousComparator!;
     }
 
     final String bootstrap = TestGoldenComparatorProcess.generateBootstrap(_fileSystem.file(testUri), testUri, logger: _logger);
@@ -68,7 +68,7 @@ class TestGoldenComparator {
     _previousComparator = TestGoldenComparatorProcess(process, logger: _logger);
     _previousTestUri = testUri;
 
-    return _previousComparator;
+    return _previousComparator!;
   }
 
   Future<Process?> _startProcess(String testBootstrap) async {
@@ -100,7 +100,11 @@ class TestGoldenComparator {
 
   Future<String?> compareGoldens(Uri testUri, Uint8List bytes, Uri goldenKey, bool? updateGoldens) async {
     final File imageFile = await (await tempDir.createTemp('image')).childFile('image').writeAsBytes(bytes);
-    final TestGoldenComparatorProcess process = await (_processForTestFile(testUri) as FutureOr<TestGoldenComparatorProcess>);
+    final TestGoldenComparatorProcess? process = await _processForTestFile(testUri);
+    if (process == null) {
+      return 'process was null';
+    }
+
     process.sendCommand(imageFile, goldenKey, updateGoldens);
 
     final Map<String, dynamic> result = await process.getResponse();

packages/flutter_tools/test/general.shard/drive/drive_service_test.dart

@@ -2,14 +2,13 @@
 // 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/file.dart';
 import 'package:file/memory.dart';
 import 'package:flutter_tools/src/application_package.dart';
 import 'package:flutter_tools/src/base/dds.dart';
+import 'package:flutter_tools/src/base/io.dart' as io;
 import 'package:flutter_tools/src/base/logger.dart';
 import 'package:flutter_tools/src/base/process.dart';
 import 'package:flutter_tools/src/build_info.dart';
@@ -19,7 +18,6 @@ import 'package:flutter_tools/src/drive/drive_service.dart';
 import 'package:flutter_tools/src/resident_runner.dart';
 import 'package:flutter_tools/src/version.dart';
 import 'package:flutter_tools/src/vmservice.dart';
-import 'package:meta/meta.dart';
 import 'package:package_config/package_config_types.dart';
 import 'package:test/fake.dart';
 import 'package:vm_service/vm_service.dart' as vm_service;
@@ -425,10 +423,10 @@ void main() {
 }
 
 FlutterDriverService setUpDriverService({
-  Logger logger,
-  ProcessManager processManager,
-  FlutterVmService vmService,
-  DevtoolsLauncher devtoolsLauncher,
+  Logger? logger,
+  ProcessManager? processManager,
+  FlutterVmService? vmService,
+  DevtoolsLauncher? devtoolsLauncher,
 }) {
   logger ??= BufferLogger.test();
   return FlutterDriverService(
@@ -441,14 +439,14 @@ FlutterDriverService setUpDriverService({
     dartSdkPath: 'dart',
     devtoolsLauncher: devtoolsLauncher ?? FakeDevtoolsLauncher(),
     vmServiceConnector: (Uri httpUri, {
-      ReloadSources reloadSources,
-      Restart restart,
-      CompileExpression compileExpression,
-      GetSkSLMethod getSkSLMethod,
-      PrintStructuredErrorLogMethod printStructuredErrorLogMethod,
-      Object compression,
-      Device device,
-      @required Logger logger,
+      ReloadSources? reloadSources,
+      Restart? restart,
+      CompileExpression? compileExpression,
+      GetSkSLMethod? getSkSLMethod,
+      PrintStructuredErrorLogMethod? printStructuredErrorLogMethod,
+      io.CompressionOptions compression = io.CompressionOptions.compressionDefault,
+      Device? device,
+      required Logger logger,
     }) async {
       assert(logger != null);
       if (httpUri.scheme != 'http') {
@@ -457,7 +455,7 @@ FlutterDriverService setUpDriverService({
       if (httpUri.path.endsWith('/ws')) {
         fail('Expected HTTP uri to not contain `/ws`, found $httpUri');
       }
-      return vmService;
+      return vmService!;
     }
   );
 }
@@ -470,8 +468,8 @@ class FakeApplicationPackageFactory extends Fake implements ApplicationPackageFa
   @override
   Future<ApplicationPackage> getPackageForPlatform(
     TargetPlatform platform, {
-    BuildInfo buildInfo,
-    File applicationBinary,
+    BuildInfo? buildInfo,
+    File? applicationBinary,
   }) async => applicationPackage;
 }
 
@@ -505,20 +503,20 @@ class FakeDevice extends Fake implements Device {
 
   @override
   Future<DeviceLogReader> getLogReader({
-    covariant ApplicationPackage app,
+    covariant ApplicationPackage? app,
     bool includePastLogs = false,
   }) async => NoOpDeviceLogReader('test');
 
   @override
   Future<LaunchResult> startApp(
     covariant ApplicationPackage package, {
-    String mainPath,
-    String route,
-    DebuggingOptions debuggingOptions,
-    Map<String, dynamic> platformArgs,
+    String? mainPath,
+    String? route,
+    required DebuggingOptions debuggingOptions,
+    Map<String, Object?> platformArgs = const <String, Object?>{},
     bool prebuiltApplication = false,
     bool ipv6 = false,
-    String userIdentifier,
+    String? userIdentifier,
     }) async {
     if (failOnce) {
       failOnce = false;
@@ -528,13 +526,13 @@ class FakeDevice extends Fake implements Device {
   }
 
   @override
-  Future<bool> stopApp(covariant ApplicationPackage app, {String userIdentifier}) async {
+  Future<bool> stopApp(covariant ApplicationPackage app, {String? userIdentifier}) async {
     didStopApp = true;
     return true;
   }
 
   @override
-  Future<bool> uninstallApp(covariant ApplicationPackage app, {String userIdentifier}) async {
+  Future<bool> uninstallApp(covariant ApplicationPackage app, {String? userIdentifier}) async {
     didUninstallApp = true;
     return true;
   }
@@ -555,10 +553,10 @@ class FakeDartDevelopmentService extends Fake implements DartDevelopmentService
   @override
   Future<void> startDartDevelopmentService(
     Uri observatoryUri, {
-    @required Logger logger,
-    int hostPort,
-    bool ipv6,
-    bool disableServiceAuthCodes,
+    required Logger logger,
+    int? hostPort,
+    bool? ipv6,
+    bool? disableServiceAuthCodes,
     bool cacheStartupProfile = false,
   }) async {
     started = true;
@@ -575,7 +573,7 @@ class FakeDevtoolsLauncher extends Fake implements DevtoolsLauncher {
   final Completer<void> _processStarted = Completer<void>();
 
   @override
-  Future<void> launch(Uri vmServiceUri, {List<String> additionalArguments}) {
+  Future<void> launch(Uri vmServiceUri, {List<String>? additionalArguments}) {
     _processStarted.complete();
     return Completer<void>().future;
   }

packages/flutter_tools/test/general.shard/web/golden_comparator_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 'dart:convert';
 import 'dart:typed_data';
@@ -28,7 +26,7 @@ final Uint8List imageBytes = Uint8List.fromList(<int>[1, 2, 3, 4, 5]);
 void main() {
 
   group('Test that TestGoldenComparator', () {
-    FakeProcessManager processManager;
+    late FakeProcessManager processManager;
 
     setUp(() {
       processManager = FakeProcessManager.empty();
@@ -63,7 +61,7 @@ void main() {
         webRenderer: WebRendererMode.html,
       );
 
-      final String result = await comparator.compareGoldens(testUri, imageBytes, goldenKey, false);
+      final String? result = await comparator.compareGoldens(testUri, imageBytes, goldenKey, false);
       expect(result, null);
     });
 
@@ -92,7 +90,7 @@ void main() {
         webRenderer: WebRendererMode.canvaskit,
       );
 
-      final String result = await comparator.compareGoldens(testUri, imageBytes, goldenKey, false);
+      final String? result = await comparator.compareGoldens(testUri, imageBytes, goldenKey, false);
       expect(result, 'some message');
     });
 
@@ -125,10 +123,10 @@ void main() {
         webRenderer: WebRendererMode.html,
       );
 
-      final String result1 = await comparator.compareGoldens(testUri, imageBytes, goldenKey, false);
+      final String? result1 = await comparator.compareGoldens(testUri, imageBytes, goldenKey, false);
       expect(result1, 'some message');
 
-      final String result2 = await comparator.compareGoldens(testUri, imageBytes, goldenKey2, false);
+      final String? result2 = await comparator.compareGoldens(testUri, imageBytes, goldenKey2, false);
       expect(result2, 'some other message');
     });
 
@@ -170,10 +168,10 @@ void main() {
         webRenderer: WebRendererMode.canvaskit,
       );
 
-      final String result1 = await comparator.compareGoldens(testUri, imageBytes, goldenKey, false);
+      final String? result1 = await comparator.compareGoldens(testUri, imageBytes, goldenKey, false);
       expect(result1, 'some message');
 
-      final String result2 = await comparator.compareGoldens(testUri2, imageBytes, goldenKey2, false);
+      final String? result2 = await comparator.compareGoldens(testUri2, imageBytes, goldenKey2, false);
       expect(result2, 'some other message');
     });
 
@@ -205,7 +203,7 @@ void main() {
         webRenderer: WebRendererMode.html,
       );
 
-      final String result = await comparator.compareGoldens(testUri, imageBytes, goldenKey, false);
+      final String? result = await comparator.compareGoldens(testUri, imageBytes, goldenKey, false);
       expect(result, null);
 
       await comparator.close();