Migrate android_console to null safety (#78923)

packages/flutter_tools/lib/src/android/android_console.dart

@@ -2,9 +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 'package:async/async.dart';
+
 import '../base/io.dart';
 import '../convert.dart';
 
@@ -28,20 +27,20 @@ typedef AndroidConsoleSocketFactory = Future<Socket> Function(String host, int p
 class AndroidConsole {
   AndroidConsole(this._socket);
 
-  Socket _socket;
-  StreamQueue<String> _queue;
+  Socket? _socket;
+  StreamQueue<String>? _queue;
 
   Future<void> connect() async {
     assert(_socket != null);
     assert(_queue == null);
 
-    _queue = StreamQueue<String>(_socket.asyncMap(ascii.decode));
+    _queue = StreamQueue<String>(_socket!.asyncMap(ascii.decode));
 
     // Discard any initial connection text.
     await _readResponse();
   }
 
-  Future<String> getAvdName() async {
+  Future<String?> getAvdName() async {
     if (_queue == null) {
       return null;
     }
@@ -55,17 +54,17 @@ class AndroidConsole {
     _queue = null;
   }
 
-  Future<String> _readResponse() async {
+  Future<String?> _readResponse() async {
     if (_queue == null) {
       return null;
     }
     final StringBuffer output = StringBuffer();
     while (true) {
-      if (!await _queue.hasNext) {
+      if (!await _queue!.hasNext) {
         destroy();
         return null;
       }
-      final String text = await _queue.next;
+      final String text = await _queue!.next;
       final String trimmedText = text.trim();
       if (trimmedText == 'OK') {
         break;

packages/flutter_tools/lib/src/base/project_migrator.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 'file_system.dart';

packages/flutter_tools/lib/src/base/utils.dart

@@ -2,7 +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 'dart:math' as math;
 

packages/flutter_tools/lib/src/ios/iproxy.dart

@@ -2,9 +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:process/process.dart';
 
 import '../base/io.dart';
@@ -16,10 +13,10 @@ import '../base/process.dart';
 /// See https://github.com/libimobiledevice/libusbmuxd.
 class IProxy {
   IProxy({
-    @required String iproxyPath,
-    @required Logger logger,
-    @required ProcessManager processManager,
-    @required MapEntry<String, String> dyLdLibEntry,
+    required String iproxyPath,
+    required Logger logger,
+    required ProcessManager processManager,
+    required MapEntry<String, String> dyLdLibEntry,
   }) : _dyLdLibEntry = dyLdLibEntry,
         _processUtils = ProcessUtils(processManager: processManager, logger: logger),
         _iproxyPath = iproxyPath;
@@ -29,8 +26,8 @@ class IProxy {
   /// This specifies the path to iproxy as 'iproxy` and the dyLdLibEntry as
   /// 'DYLD_LIBRARY_PATH: /path/to/libs'.
   factory IProxy.test({
-    @required Logger logger,
-    @required ProcessManager processManager,
+    required Logger logger,
+    required ProcessManager processManager,
   }) {
     return IProxy(
       iproxyPath: 'iproxy',

packages/flutter_tools/lib/src/ios/plist_parser.dart

@@ -2,9 +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:process/process.dart';
 
 import '../base/file_system.dart';
@@ -16,9 +13,9 @@ import '../convert.dart';
 
 class PlistParser {
   PlistParser({
-    @required FileSystem fileSystem,
-    @required Logger logger,
-    @required ProcessManager processManager,
+    required FileSystem fileSystem,
+    required Logger logger,
+    required ProcessManager processManager,
   }) : _fileSystem = fileSystem,
        _logger = logger,
        _processUtils = ProcessUtils(logger: logger, processManager: processManager);
@@ -58,7 +55,7 @@ class PlistParser {
         args,
         throwOnError: true,
       ).stdout.trim();
-      return castStringKeyedMap(json.decode(jsonContent));
+      return castStringKeyedMap(json.decode(jsonContent)) ?? const <String, dynamic>{};
     } on ProcessException catch (error) {
       _logger.printTrace('$error');
       return const <String, dynamic>{};
@@ -74,7 +71,7 @@ class PlistParser {
   /// If [key] is not found in the property list, this will return null.
   ///
   /// The [plistFilePath] and [key] arguments must not be null.
-  String getValueFromFile(String plistFilePath, String key) {
+  String? getValueFromFile(String plistFilePath, String key) {
     assert(key != null);
     final Map<String, dynamic> parsed = parseFile(plistFilePath);
     return parsed[key] as String;

packages/flutter_tools/test/src/io.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:io' as io show IOOverrides, Directory, File, Link;
 
 import 'package:flutter_tools/src/base/file_system.dart';
@@ -19,17 +17,17 @@ import 'package:flutter_tools/src/base/file_system.dart';
 /// The only safe delegate types are those that do not call out to `dart:io`,
 /// like the [MemoryFileSystem].
 class FlutterIOOverrides extends io.IOOverrides {
-  FlutterIOOverrides({ FileSystem fileSystem })
+  FlutterIOOverrides({ FileSystem? fileSystem })
     : _fileSystemDelegate = fileSystem;
 
-  final FileSystem _fileSystemDelegate;
+  final FileSystem? _fileSystemDelegate;
 
   @override
   io.Directory createDirectory(String path) {
     if (_fileSystemDelegate == null) {
       return super.createDirectory(path);
     }
-    return _fileSystemDelegate.directory(path);
+    return _fileSystemDelegate!.directory(path);
   }
 
   @override
@@ -37,7 +35,7 @@ class FlutterIOOverrides extends io.IOOverrides {
     if (_fileSystemDelegate == null) {
       return super.createFile(path);
     }
-    return _fileSystemDelegate.file(path);
+    return _fileSystemDelegate!.file(path);
   }
 
   @override
@@ -45,7 +43,7 @@ class FlutterIOOverrides extends io.IOOverrides {
     if (_fileSystemDelegate == null) {
       return super.createLink(path);
     }
-    return _fileSystemDelegate.link(path);
+    return _fileSystemDelegate!.link(path);
   }
 
   @override
@@ -53,7 +51,7 @@ class FlutterIOOverrides extends io.IOOverrides {
     if (_fileSystemDelegate == null) {
       return super.fsWatch(path, events, recursive);
     }
-    return _fileSystemDelegate.file(path).watch(events: events, recursive: recursive);
+    return _fileSystemDelegate!.file(path).watch(events: events, recursive: recursive);
   }
 
   @override
@@ -61,7 +59,7 @@ class FlutterIOOverrides extends io.IOOverrides {
     if (_fileSystemDelegate == null) {
       return super.fsWatchIsSupported();
     }
-    return _fileSystemDelegate.isWatchSupported;
+    return _fileSystemDelegate!.isWatchSupported;
   }
 
   @override
@@ -69,7 +67,7 @@ class FlutterIOOverrides extends io.IOOverrides {
     if (_fileSystemDelegate == null) {
       return super.fseGetType(path, followLinks);
     }
-    return _fileSystemDelegate.type(path, followLinks: followLinks ?? true);
+    return _fileSystemDelegate!.type(path, followLinks: followLinks);
   }
 
   @override
@@ -77,7 +75,7 @@ class FlutterIOOverrides extends io.IOOverrides {
     if (_fileSystemDelegate == null) {
       return super.fseGetTypeSync(path, followLinks);
     }
-    return _fileSystemDelegate.typeSync(path, followLinks: followLinks ?? true);
+    return _fileSystemDelegate!.typeSync(path, followLinks: followLinks);
   }
 
   @override
@@ -85,7 +83,7 @@ class FlutterIOOverrides extends io.IOOverrides {
     if (_fileSystemDelegate == null) {
       return super.fseIdentical(path1, path2);
     }
-    return _fileSystemDelegate.identical(path1, path2);
+    return _fileSystemDelegate!.identical(path1, path2);
   }
 
   @override
@@ -93,7 +91,7 @@ class FlutterIOOverrides extends io.IOOverrides {
     if (_fileSystemDelegate == null) {
       return super.fseIdenticalSync(path1, path2);
     }
-    return _fileSystemDelegate.identicalSync(path1, path2);
+    return _fileSystemDelegate!.identicalSync(path1, path2);
   }
 
   @override
@@ -101,7 +99,7 @@ class FlutterIOOverrides extends io.IOOverrides {
     if (_fileSystemDelegate == null) {
       return super.getCurrentDirectory();
     }
-    return _fileSystemDelegate.currentDirectory;
+    return _fileSystemDelegate!.currentDirectory;
   }
 
   @override
@@ -109,7 +107,7 @@ class FlutterIOOverrides extends io.IOOverrides {
     if (_fileSystemDelegate == null) {
       return super.getSystemTempDirectory();
     }
-    return _fileSystemDelegate.systemTempDirectory;
+    return _fileSystemDelegate!.systemTempDirectory;
   }
 
   @override
@@ -117,7 +115,7 @@ class FlutterIOOverrides extends io.IOOverrides {
     if (_fileSystemDelegate == null) {
       return super.setCurrentDirectory(path);
     }
-    _fileSystemDelegate.currentDirectory = path;
+    _fileSystemDelegate!.currentDirectory = path;
   }
 
   @override
@@ -125,7 +123,7 @@ class FlutterIOOverrides extends io.IOOverrides {
     if (_fileSystemDelegate == null) {
       return super.stat(path);
     }
-    return _fileSystemDelegate.stat(path);
+    return _fileSystemDelegate!.stat(path);
   }
 
   @override
@@ -133,6 +131,6 @@ class FlutterIOOverrides extends io.IOOverrides {
     if (_fileSystemDelegate == null) {
       return super.statSync(path);
     }
-    return _fileSystemDelegate.statSync(path);
+    return _fileSystemDelegate!.statSync(path);
   }
 }

packages/flutter_tools/test/src/test_wrapper.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:test/test.dart' hide isInstanceOf;
 
 export 'package:test/test.dart' hide isInstanceOf;