Migrate channel, clean and a few other commands to null safety (#92950)

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

@@ -6,7 +6,7 @@
 /// where the tool should exit with a clear message to the user
 /// and no stack trace unless the --verbose option is specified.
 /// For example: network errors.
-Never throwToolExit(String message, { int? exitCode }) {
+Never throwToolExit(String? message, { int? exitCode }) {
   throw ToolExit(message, exitCode: exitCode);
 }
 

packages/flutter_tools/lib/src/commands/channel.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 '../base/common.dart';
 import '../cache.dart';
 import '../globals.dart' as globals;
@@ -16,7 +14,6 @@ class ChannelCommand extends FlutterCommand {
       'all',
       abbr: 'a',
       help: 'Include all the available branches (including local branches) when listing channels.',
-      defaultsTo: false,
       hide: !verboseHelp,
     );
   }
@@ -31,29 +28,30 @@ class ChannelCommand extends FlutterCommand {
   final String category = FlutterCommandCategory.sdk;
 
   @override
-  String get invocation => '${runner.executableName} $name [<channel-name>]';
+  String get invocation => '${runner?.executableName} $name [<channel-name>]';
 
   @override
   Future<Set<DevelopmentArtifact>> get requiredArtifacts async => const <DevelopmentArtifact>{};
 
   @override
   Future<FlutterCommandResult> runCommand() async {
-    switch (argResults.rest.length) {
+    final List<String> rest = argResults?.rest ?? <String>[];
+    switch (rest.length) {
       case 0:
         await _listChannels(
           showAll: boolArg('all'),
-          verbose: globalResults['verbose'] as bool,
+          verbose: globalResults?['verbose'] == true,
         );
         return FlutterCommandResult.success();
       case 1:
-        await _switchChannel(argResults.rest[0]);
+        await _switchChannel(rest[0]);
         return FlutterCommandResult.success();
       default:
         throw ToolExit('Too many arguments.\n$usage');
     }
   }
 
-  Future<void> _listChannels({ bool showAll, bool verbose }) async {
+  Future<void> _listChannels({ required bool showAll, required bool verbose }) async {
     // Beware: currentBranch could contain PII. See getBranchName().
     final String currentChannel = globals.flutterVersion.channel;
     final String currentBranch = globals.flutterVersion.getBranchName();

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

@@ -2,10 +2,9 @@
 // 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 '../../src/macos/xcode.dart';
 import '../base/file_system.dart';
 import '../base/logger.dart';
 import '../build_info.dart';
@@ -40,7 +39,8 @@ class CleanCommand extends FlutterCommand {
     // Clean Xcode to remove intermediate DerivedData artifacts.
     // Do this before removing ephemeral directory, which would delete the xcworkspace.
     final FlutterProject flutterProject = FlutterProject.current();
-    if (globals.xcode.isInstalledAndMeetsVersionCheck) {
+    final Xcode? xcode = globals.xcode;
+    if (xcode != null && xcode.isInstalledAndMeetsVersionCheck) {
       await _cleanXcode(flutterProject.ios);
       await _cleanXcode(flutterProject.macos);
     }
@@ -78,15 +78,16 @@ class CleanCommand extends FlutterCommand {
       'Cleaning Xcode workspace...',
     );
     try {
+      final XcodeProjectInterpreter xcodeProjectInterpreter = globals.xcodeProjectInterpreter!;
       final Directory xcodeWorkspace = xcodeProject.xcodeWorkspace;
-      final XcodeProjectInfo projectInfo = await globals.xcodeProjectInterpreter.getInfo(xcodeWorkspace.parent.path);
+      final XcodeProjectInfo projectInfo = await xcodeProjectInterpreter.getInfo(xcodeWorkspace.parent.path);
       for (final String scheme in projectInfo.schemes) {
-        await globals.xcodeProjectInterpreter.cleanWorkspace(xcodeWorkspace.path, scheme, verbose: _verbose);
+        await xcodeProjectInterpreter.cleanWorkspace(xcodeWorkspace.path, scheme, verbose: _verbose);
       }
     } on Exception catch (error) {
       globals.printTrace('Could not clean Xcode workspace: $error');
     } finally {
-      xcodeStatus?.stop();
+      xcodeStatus.stop();
     }
   }
 

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

@@ -2,8 +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 '../../src/android/android_sdk.dart';
+import '../../src/android/android_studio.dart';
 import '../base/common.dart';
 import '../convert.dart';
 import '../features.dart';
@@ -14,7 +14,6 @@ import '../runner/flutter_command.dart';
 class ConfigCommand extends FlutterCommand {
   ConfigCommand({ bool verboseHelp = false }) {
     argParser.addFlag('analytics',
-      negatable: true,
       help: 'Enable or disable reporting anonymously tool usage statistics and crash reports.');
     argParser.addFlag('clear-ios-signing-cert',
       negatable: false,
@@ -28,13 +27,13 @@ class ConfigCommand extends FlutterCommand {
       hide: !verboseHelp,
       help: 'Print config values as json.');
     for (final Feature feature in allFeatures) {
-      if (feature.configSetting == null) {
+      final String? configSetting = feature.configSetting;
+      if (configSetting == null) {
         continue;
       }
       argParser.addFlag(
-        feature.configSetting,
+        configSetting,
         help: feature.generateHelpMessage(),
-        negatable: true,
       );
     }
     argParser.addFlag(
@@ -70,15 +69,16 @@ class ConfigCommand extends FlutterCommand {
     final Map<String, Feature> featuresByName = <String, Feature>{};
     final String channel = globals.flutterVersion.channel;
     for (final Feature feature in allFeatures) {
-      if (feature.configSetting != null) {
-        featuresByName[feature.configSetting] = feature;
+      final String? configSetting = feature.configSetting;
+      if (configSetting != null) {
+        featuresByName[configSetting] = feature;
       }
     }
     String values = globals.config.keys
         .map<String>((String key) {
           String configFooter = '';
           if (featuresByName.containsKey(key)) {
-            final FeatureChannelSetting setting = featuresByName[key].getSettingForChannel(channel);
+            final FeatureChannelSetting setting = featuresByName[key]!.getSettingForChannel(channel);
             if (!setting.available) {
               configFooter = '(Unavailable)';
             }
@@ -97,7 +97,7 @@ class ConfigCommand extends FlutterCommand {
 
   /// Return null to disable analytics recording of the `config` command.
   @override
-  Future<String> get usagePath async => null;
+  Future<String?> get usagePath async => null;
 
   @override
   Future<FlutterCommandResult> runCommand() async {
@@ -108,14 +108,15 @@ class ConfigCommand extends FlutterCommand {
 
     if (boolArg('clear-features')) {
       for (final Feature feature in allFeatures) {
-        if (feature.configSetting != null) {
-          globals.config.removeValue(feature.configSetting);
+        final String? configSetting = feature.configSetting;
+        if (configSetting != null) {
+          globals.config.removeValue(configSetting);
         }
       }
       return FlutterCommandResult.success();
     }
 
-    if (argResults.wasParsed('analytics')) {
+    if (argResults?.wasParsed('analytics') == true) {
       final bool value = boolArg('analytics');
       // The tool sends the analytics event *before* toggling the flag
       // intentionally to be sure that opt-out events are sent correctly.
@@ -130,20 +131,20 @@ class ConfigCommand extends FlutterCommand {
       globals.printStatus('Analytics reporting ${value ? 'enabled' : 'disabled'}.');
     }
 
-    if (argResults.wasParsed('android-sdk')) {
-      _updateConfig('android-sdk', stringArg('android-sdk'));
+    if (argResults?.wasParsed('android-sdk') == true) {
+      _updateConfig('android-sdk', stringArg('android-sdk')!);
     }
 
-    if (argResults.wasParsed('android-studio-dir')) {
-      _updateConfig('android-studio-dir', stringArg('android-studio-dir'));
+    if (argResults?.wasParsed('android-studio-dir') == true) {
+      _updateConfig('android-studio-dir', stringArg('android-studio-dir')!);
     }
 
-    if (argResults.wasParsed('clear-ios-signing-cert')) {
+    if (argResults?.wasParsed('clear-ios-signing-cert') == true) {
       _updateConfig('ios-signing-cert', '');
     }
 
-    if (argResults.wasParsed('build-dir')) {
-      final String buildDir = stringArg('build-dir');
+    if (argResults?.wasParsed('build-dir') == true) {
+      final String buildDir = stringArg('build-dir')!;
       if (globals.fs.path.isAbsolute(buildDir)) {
         throwToolExit('build-dir should be a relative path');
       }
@@ -151,17 +152,18 @@ class ConfigCommand extends FlutterCommand {
     }
 
     for (final Feature feature in allFeatures) {
-      if (feature.configSetting == null) {
+      final String? configSetting = feature.configSetting;
+      if (configSetting == null) {
         continue;
       }
-      if (argResults.wasParsed(feature.configSetting)) {
-        final bool keyValue = boolArg(feature.configSetting);
-        globals.config.setValue(feature.configSetting, keyValue);
-        globals.printStatus('Setting "${feature.configSetting}" value to "$keyValue".');
+      if (argResults?.wasParsed(configSetting) == true) {
+        final bool keyValue = boolArg(configSetting);
+        globals.config.setValue(configSetting, keyValue);
+        globals.printStatus('Setting "$configSetting" value to "$keyValue".');
       }
     }
 
-    if (argResults.arguments.isEmpty) {
+    if (argResults == null || argResults!.arguments.isEmpty) {
       globals.printStatus(usage);
     } else {
       globals.printStatus('\nYou may need to restart any open editors for them to read new settings.');
@@ -172,17 +174,19 @@ class ConfigCommand extends FlutterCommand {
 
   Future<void> handleMachine() async {
     // Get all the current values.
-    final Map<String, dynamic> results = <String, dynamic>{};
+    final Map<String, Object?> results = <String, Object?>{};
     for (final String key in globals.config.keys) {
       results[key] = globals.config.getValue(key);
     }
 
     // Ensure we send any calculated ones, if overrides don't exist.
-    if (results['android-studio-dir'] == null && globals.androidStudio != null) {
-      results['android-studio-dir'] = globals.androidStudio.directory;
+    final AndroidStudio? androidStudio = globals.androidStudio;
+    if (results['android-studio-dir'] == null && androidStudio != null) {
+      results['android-studio-dir'] = androidStudio.directory;
     }
-    if (results['android-sdk'] == null && globals.androidSdk != null) {
-      results['android-sdk'] = globals.androidSdk.directory.path;
+    final AndroidSdk? androidSdk = globals.androidSdk;
+    if (results['android-sdk'] == null && androidSdk != null) {
+      results['android-sdk'] = androidSdk.directory.path;
     }
 
     globals.printStatus(const JsonEncoder.withIndent('  ').convert(results));

packages/flutter_tools/lib/src/commands/debug_adapter.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 '../debug_adapters/server.dart';
@@ -31,7 +29,6 @@ class DebugAdapterCommand extends FlutterCommand {
     argParser
       .addFlag(
         'test',
-        defaultsTo: false,
         help: 'Whether to use the "flutter test" debug adapter to run tests'
             ' and emit custom events for test progress/results.',
       );
@@ -59,9 +56,9 @@ class DebugAdapterCommand extends FlutterCommand {
       globals.stdio.stdout.nonBlocking,
       fileSystem: globals.fs,
       platform: globals.platform,
-      ipv6: ipv6,
+      ipv6: ipv6 == true,
       enableDds: enableDds,
-      test: boolArg('test') ?? false,
+      test: boolArg('test'),
     );
 
     await server.channel.closed;

packages/flutter_tools/lib/src/commands/devices.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 '../base/common.dart';
 import '../base/utils.dart';
 import '../convert.dart';
@@ -20,7 +18,6 @@ class DevicesCommand extends FlutterCommand {
     argParser.addOption(
       'timeout',
       abbr: 't',
-      defaultsTo: null,
       help: '(deprecated) This option has been replaced by "--${FlutterOptions.kDeviceTimeout}".',
       hide: !verboseHelp,
     );
@@ -37,9 +34,9 @@ class DevicesCommand extends FlutterCommand {
   final String category = FlutterCommandCategory.tools;
 
   @override
-  Duration get deviceDiscoveryTimeout {
-    if (argResults['timeout'] != null) {
-      final int timeoutSeconds = int.tryParse(stringArg('timeout'));
+  Duration? get deviceDiscoveryTimeout {
+    if (argResults?['timeout'] != null) {
+      final int? timeoutSeconds = int.tryParse(stringArg('timeout')!);
       if (timeoutSeconds == null) {
         throwToolExit('Could not parse -t/--timeout argument. It must be an integer.');
       }
@@ -50,7 +47,7 @@ class DevicesCommand extends FlutterCommand {
 
   @override
   Future<void> validateCommand() {
-    if (argResults['timeout'] != null) {
+    if (argResults?['timeout'] != null) {
       globals.printError('${globals.logger.terminal.warningMark} The "--timeout" argument is deprecated; use "--${FlutterOptions.kDeviceTimeout}" instead.');
     }
     return super.validateCommand();
@@ -58,14 +55,14 @@ class DevicesCommand extends FlutterCommand {
 
   @override
   Future<FlutterCommandResult> runCommand() async {
-    if (!globals.doctor.canListAnything) {
+    if (globals.doctor?.canListAnything != true) {
       throwToolExit(
         "Unable to locate a development device; please run 'flutter doctor' for "
         'information about installing additional components.',
         exitCode: 1);
     }
 
-    final List<Device> devices = await globals.deviceManager.refreshAllConnectedDevices(timeout: deviceDiscoveryTimeout);
+    final List<Device> devices = await globals.deviceManager?.refreshAllConnectedDevices(timeout: deviceDiscoveryTimeout) ?? <Device>[];
 
     if (boolArg('machine')) {
       await printDevicesAsJson(devices);
@@ -93,7 +90,7 @@ class DevicesCommand extends FlutterCommand {
   }
 
   Future<void> _printDiagnostics() async {
-    final List<String> diagnostics = await globals.deviceManager.getDeviceDiagnostics();
+    final List<String> diagnostics = await globals.deviceManager?.getDeviceDiagnostics() ?? <String>[];
     if (diagnostics.isNotEmpty) {
       globals.printStatus('');
       for (final String diagnostic in diagnostics) {

packages/flutter_tools/lib/src/commands/logs.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 '../base/common.dart';
@@ -34,10 +32,10 @@ class LogsCommand extends FlutterCommand {
   @override
   Future<Set<DevelopmentArtifact>> get requiredArtifacts async => const <DevelopmentArtifact>{};
 
-  Device device;
+  Device? device;
 
   @override
-  Future<FlutterCommandResult> verifyThenRunCommand(String commandPath) async {
+  Future<FlutterCommandResult> verifyThenRunCommand(String? commandPath) async {
     device = await findTargetDevice(includeUnsupportedDevices: true);
     if (device == null) {
       throwToolExit(null);
@@ -47,11 +45,12 @@ class LogsCommand extends FlutterCommand {
 
   @override
   Future<FlutterCommandResult> runCommand() async {
+    final Device cachedDevice = device!;
     if (boolArg('clear')) {
-      device.clearLogs();
+      cachedDevice.clearLogs();
     }
 
-    final DeviceLogReader logReader = await device.getLogReader();
+    final DeviceLogReader logReader = await cachedDevice.getLogReader();
 
     globals.printStatus('Showing $logReader logs:');
 

packages/flutter_tools/lib/src/commands/make_host_app_editable.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 '../runner/flutter_command.dart';
 
 class MakeHostAppEditableCommand extends FlutterCommand {