Declare locals final where not reassigned (flutter_tools) (#8570)

packages/flutter_tools/bin/fuchsia_builder.dart

@@ -35,7 +35,7 @@ const List<String> _kRequiredOptions = const <String>[
 ];
 
 Future<Null> main(List<String> args) async {
-  AppContext executableContext = new AppContext();
+  final AppContext executableContext = new AppContext();
   executableContext.setVariable(Logger, new StdoutLogger());
   executableContext.runInZone(() {
     // Initialize the context with some defaults.
@@ -66,7 +66,7 @@ Future<Null> run(List<String> args) async {
     exit(1);
   }
   Cache.flutterRoot = platform.environment['FLUTTER_ROOT'];
-  String outputPath = argResults[_kOptionOutput];
+  final String outputPath = argResults[_kOptionOutput];
   try {
     await assemble(
       outputPath: outputPath,

packages/flutter_tools/lib/executable.dart

@@ -60,10 +60,10 @@ import 'src/usage.dart';
 ///
 /// This function is intended to be used from the `flutter` command line tool.
 Future<Null> main(List<String> args) async {
-  bool verbose = args.contains('-v') || args.contains('--verbose');
-  bool help = args.contains('-h') || args.contains('--help') ||
+  final bool verbose = args.contains('-v') || args.contains('--verbose');
+  final bool help = args.contains('-h') || args.contains('--help') ||
       (args.isNotEmpty && args.first == 'help') || (args.length == 1 && verbose);
-  bool verboseHelp = help && verbose;
+  final bool verboseHelp = help && verbose;
 
   await run(args, <FlutterCommand>[
     new AnalyzeCommand(verboseHelp: verboseHelp),
@@ -104,11 +104,11 @@ Future<int> run(List<String> args, List<FlutterCommand> subCommands, {
     args.removeWhere((String option) => option == '-v' || option == '--verbose');
   }
 
-  FlutterCommandRunner runner = new FlutterCommandRunner(verboseHelp: verboseHelp);
+  final FlutterCommandRunner runner = new FlutterCommandRunner(verboseHelp: verboseHelp);
   subCommands.forEach(runner.addCommand);
 
   // Construct a context.
-  AppContext _executableContext = new AppContext();
+  final AppContext _executableContext = new AppContext();
 
   // Make the context current.
   return await _executableContext.runInZone(() async {
@@ -140,7 +140,7 @@ Future<int> run(List<String> args, List<FlutterCommand> subCommands, {
     // Initialize the system locale.
     await intl.findSystemLocale();
 
-    Completer<int> runCompleter = new Completer<int>();
+    final Completer<int> runCompleter = new Completer<int>();
     Chain.capture<Future<Null>>(() async {
       await runner.run(args);
       await _exit(0);
@@ -206,7 +206,7 @@ Future<int> _handleToolError(
         flutterVersion: flutterVersion,
       );
       try {
-        File file = await _createLocalCrashReport(args, error, chain);
+        final File file = await _createLocalCrashReport(args, error, chain);
         stderr.writeln(
             'Crash report written to ${file.path};\n'
                 'please let us know at https://github.com/flutter/flutter/issues.',
@@ -235,7 +235,7 @@ FileSystem crashFileSystem = new LocalFileSystem();
 Future<File> _createLocalCrashReport(List<String> args, dynamic error, Chain chain) async {
   File crashFile = getUniqueFile(crashFileSystem.currentDirectory, 'flutter', 'log');
 
-  StringBuffer buffer = new StringBuffer();
+  final StringBuffer buffer = new StringBuffer();
 
   buffer.writeln('Flutter crash report; please file at https://github.com/flutter/flutter/issues.\n');
 
@@ -267,8 +267,8 @@ Future<File> _createLocalCrashReport(List<String> args, dynamic error, Chain cha
 
 Future<String> _doctorText() async {
   try {
-    BufferLogger logger = new BufferLogger();
-    AppContext appContext = new AppContext();
+    final BufferLogger logger = new BufferLogger();
+    final AppContext appContext = new AppContext();
 
     appContext.setVariable(Logger, logger);
 
@@ -287,7 +287,7 @@ Future<int> _exit(int code) async {
   // Send any last analytics calls that are in progress without overly delaying
   // the tool's exit (we wait a maximum of 250ms).
   if (flutterUsage.enabled) {
-    Stopwatch stopwatch = new Stopwatch()..start();
+    final Stopwatch stopwatch = new Stopwatch()..start();
     await flutterUsage.ensureAnalyticsSent();
     printTrace('ensureAnalyticsSent: ${stopwatch.elapsedMilliseconds}ms');
   }
@@ -295,7 +295,7 @@ Future<int> _exit(int code) async {
   // Run shutdown hooks before flushing logs
   await runShutdownHooks();
 
-  Completer<Null> completer = new Completer<Null>();
+  final Completer<Null> completer = new Completer<Null>();
 
   // Give the task / timer queue one cycle through before we hard exit.
   Timer.run(() {

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

@@ -51,7 +51,7 @@ class Adb {
   /// Ask the ADB server for its internal version number.
   Future<String> getServerVersion() {
     return _sendAdbServerCommand('host:version').then((String response) {
-      _AdbServerResponse adbResponse = new _AdbServerResponse(response);
+      final _AdbServerResponse adbResponse = new _AdbServerResponse(response);
       if (adbResponse.isOkay)
         return adbResponse.message;
       throw adbResponse.message;
@@ -60,11 +60,11 @@ class Adb {
 
   /// Queries the adb server for the list of connected adb devices.
   Future<List<AdbDevice>> listDevices() async {
-    String stringResponse = await _sendAdbServerCommand('host:devices-l');
-    _AdbServerResponse response = new _AdbServerResponse(stringResponse);
+    final String stringResponse = await _sendAdbServerCommand('host:devices-l');
+    final _AdbServerResponse response = new _AdbServerResponse(stringResponse);
     if (response.isFail)
       throw response.message;
-    String message = response.message.trim();
+    final String message = response.message.trim();
     if (message.isEmpty)
       return <AdbDevice>[];
     return message.split('\n').map(
@@ -73,16 +73,16 @@ class Adb {
   }
 
   Future<String> _sendAdbServerCommand(String command) async {
-    Socket socket = await Socket.connect(InternetAddress.LOOPBACK_IP_V4, adbServerPort);
+    final Socket socket = await Socket.connect(InternetAddress.LOOPBACK_IP_V4, adbServerPort);
 
     try {
       printTrace('--> $command');
       socket.add(_createAdbRequest(command));
-      List<List<int>> result = await socket.toList();
-      List<int> data = result.fold(<int>[], (List<int> previous, List<int> element) {
+      final List<List<int>> result = await socket.toList();
+      final List<int> data = result.fold(<int>[], (List<int> previous, List<int> element) {
         return previous..addAll(element);
       });
-      String stringResult = new String.fromCharCodes(data);
+      final String stringResult = new String.fromCharCodes(data);
       printTrace('<-- ${stringResult.trim()}');
       return stringResult;
     } finally {
@@ -97,7 +97,7 @@ class AdbDevice {
     // 'TA95000FQA             device usb:340787200X product:peregrine_retus model:XT1045 device:peregrine'
     // '015d172c98400a03       device usb:340787200X product:nakasi model:Nexus_7 device:grouper'
 
-    Match match = kDeviceRegex.firstMatch(deviceInfo);
+    final Match match = kDeviceRegex.firstMatch(deviceInfo);
     id = match[1];
     status = match[2];
 
@@ -106,7 +106,7 @@ class AdbDevice {
       rest = rest.trim();
       for (String data in rest.split(' ')) {
         if (data.contains(':')) {
-          List<String> fields = data.split(':');
+          final List<String> fields = data.split(':');
           _info[fields[0]] = fields[1];
         }
       }
@@ -183,11 +183,11 @@ String cleanAdbDeviceName(String name) {
 }
 
 List<int> _createAdbRequest(String payload) {
-  List<int> data = payload.codeUnits;
+  final List<int> data = payload.codeUnits;
 
   // A 4-byte hexadecimal string giving the length of the payload.
-  String prefix = data.length.toRadixString(16).padLeft(4, '0');
-  List<int> result = <int>[];
+  final String prefix = data.length.toRadixString(16).padLeft(4, '0');
+  final List<int> result = <int>[];
   result.addAll(prefix.codeUnits);
   result.addAll(data);
   return result;

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

@@ -44,7 +44,7 @@ String getAdbPath([AndroidSdk existingSdk]) {
   if (existingSdk?.adbPath != null)
     return existingSdk.adbPath;
 
-  AndroidSdk sdk = AndroidSdk.locateAndroidSdk();
+  final AndroidSdk sdk = AndroidSdk.locateAndroidSdk();
 
   if (sdk?.latestVersion == null) {
     return os.which('adb')?.path;
@@ -89,7 +89,7 @@ class AndroidSdk {
     if (aaptBin != null) {
       // Make sure we're using the aapt from the SDK.
       aaptBin = fs.file(aaptBin.resolveSymbolicLinksSync());
-      String dir = aaptBin.parent.parent.parent.path;
+      final String dir = aaptBin.parent.parent.parent.path;
       if (validSdkDirectory(dir))
         return new AndroidSdk(dir);
     }
@@ -98,7 +98,7 @@ class AndroidSdk {
     if (adbBin != null) {
       // Make sure we're using the adb from the SDK.
       adbBin = fs.file(adbBin.resolveSymbolicLinksSync());
-      String dir = adbBin.parent.parent.path;
+      final String dir = adbBin.parent.parent.path;
       if (validSdkDirectory(dir))
         return new AndroidSdk(dir);
     }
@@ -137,7 +137,7 @@ class AndroidSdk {
   void _init() {
     List<String> platforms = <String>[]; // android-22, ...
 
-    Directory platformsDir = fs.directory(fs.path.join(directory, 'platforms'));
+    final Directory platformsDir = fs.directory(fs.path.join(directory, 'platforms'));
     if (platformsDir.existsSync()) {
       platforms = platformsDir
         .listSync()
@@ -148,7 +148,7 @@ class AndroidSdk {
 
     List<Version> buildTools = <Version>[]; // 19.1.0, 22.0.1, ...
 
-    Directory buildToolsDir = fs.directory(fs.path.join(directory, 'build-tools'));
+    final Directory buildToolsDir = fs.directory(fs.path.join(directory, 'build-tools'));
     if (buildToolsDir.existsSync()) {
       buildTools = buildToolsDir
         .listSync()

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

@@ -34,7 +34,7 @@ final RegExp _dotHomeStudioVersionMatcher =
 /// Locate Gradle.
 String get gradleExecutable {
   // See if the user has explicitly configured gradle-dir.
-  String gradleDir = config.getValue('gradle-dir');
+  final String gradleDir = config.getValue('gradle-dir');
   if (gradleDir != null) {
     if (fs.isFileSync(gradleDir))
       return gradleDir;
@@ -58,9 +58,9 @@ class AndroidStudio implements Comparable<AndroidStudio> {
   List<String> _validationMessages = <String>[];
 
   factory AndroidStudio.fromMacOSBundle(String bundlePath) {
-    String studioPath = fs.path.join(bundlePath, 'Contents');
-    String plistFile = fs.path.join(studioPath, 'Info.plist');
-    String versionString =
+    final String studioPath = fs.path.join(bundlePath, 'Contents');
+    final String plistFile = fs.path.join(studioPath, 'Info.plist');
+    final String versionString =
         getValueFromFile(plistFile, kCFBundleShortVersionStringKey);
     Version version;
     if (versionString != null)
@@ -69,12 +69,12 @@ class AndroidStudio implements Comparable<AndroidStudio> {
   }
 
   factory AndroidStudio.fromHomeDot(Directory homeDotDir) {
-    Match versionMatch =
+    final Match versionMatch =
         _dotHomeStudioVersionMatcher.firstMatch(homeDotDir.basename);
     if (versionMatch?.groupCount != 2) {
       return null;
     }
-    Version version = new Version.parse(versionMatch[2]);
+    final Version version = new Version.parse(versionMatch[2]);
     if (version == null) {
       return null;
     }
@@ -103,7 +103,7 @@ class AndroidStudio implements Comparable<AndroidStudio> {
 
   @override
   int compareTo(AndroidStudio other) {
-    int result = version.compareTo(other.version);
+    final int result = version.compareTo(other.version);
     if (result == 0)
       return directory.compareTo(other.directory);
     return result;
@@ -111,7 +111,7 @@ class AndroidStudio implements Comparable<AndroidStudio> {
 
   /// Locates the newest, valid version of Android Studio.
   static AndroidStudio latestValid() {
-    String configuredStudio = config.getValue('android-studio-dir');
+    final String configuredStudio = config.getValue('android-studio-dir');
     if (configuredStudio != null) {
       String configuredStudioPath = configuredStudio;
       if (platform.isMacOS && !configuredStudioPath.endsWith('Contents'))
@@ -121,7 +121,7 @@ class AndroidStudio implements Comparable<AndroidStudio> {
     }
 
     // Find all available Studio installations.
-    List<AndroidStudio> studios = allInstalled();
+    final List<AndroidStudio> studios = allInstalled();
     if (studios.isEmpty) {
       return null;
     }
@@ -134,13 +134,13 @@ class AndroidStudio implements Comparable<AndroidStudio> {
       platform.isMacOS ? _allMacOS() : _allLinuxOrWindows();
 
   static List<AndroidStudio> _allMacOS() {
-    List<FileSystemEntity> candidatePaths = <FileSystemEntity>[];
+    final List<FileSystemEntity> candidatePaths = <FileSystemEntity>[];
 
     void _checkForStudio(String path) {
       if (!fs.isDirectorySync(path))
         return;
       try {
-        Iterable<Directory> directories = fs
+        final Iterable<Directory> directories = fs
             .directory(path)
             .listSync()
             .where((FileSystemEntity e) => e is Directory);
@@ -159,7 +159,7 @@ class AndroidStudio implements Comparable<AndroidStudio> {
     _checkForStudio('/Applications');
     _checkForStudio(fs.path.join(homeDirPath, 'Applications'));
 
-    String configuredStudioDir = config.getValue('android-studio-dir');
+    final String configuredStudioDir = config.getValue('android-studio-dir');
     if (configuredStudioDir != null) {
       FileSystemEntity configuredStudio = fs.file(configuredStudioDir);
       if (configuredStudio.basename == 'Contents') {
@@ -178,7 +178,7 @@ class AndroidStudio implements Comparable<AndroidStudio> {
   }
 
   static List<AndroidStudio> _allLinuxOrWindows() {
-    List<AndroidStudio> studios = <AndroidStudio>[];
+    final List<AndroidStudio> studios = <AndroidStudio>[];
 
     bool _hasStudioAt(String path, {Version newerThan}) {
       return studios.any((AndroidStudio studio) {
@@ -194,7 +194,7 @@ class AndroidStudio implements Comparable<AndroidStudio> {
     // pointing to the same installation, so we grab only the latest one.
     for (FileSystemEntity entity in fs.directory(homeDirPath).listSync()) {
       if (entity is Directory && entity.basename.startsWith('.AndroidStudio')) {
-        AndroidStudio studio = new AndroidStudio.fromHomeDot(entity);
+        final AndroidStudio studio = new AndroidStudio.fromHomeDot(entity);
         if (studio != null &&
             !_hasStudioAt(studio.directory, newerThan: studio.version)) {
           studios.removeWhere(
@@ -204,7 +204,7 @@ class AndroidStudio implements Comparable<AndroidStudio> {
       }
     }
 
-    String configuredStudioDir = config.getValue('android-studio-dir');
+    final String configuredStudioDir = config.getValue('android-studio-dir');
     if (configuredStudioDir != null && !_hasStudioAt(configuredStudioDir)) {
       studios.add(new AndroidStudio(configuredStudioDir,
           configured: configuredStudioDir));
@@ -244,7 +244,7 @@ class AndroidStudio implements Comparable<AndroidStudio> {
       gradlePaths = fs.directory(fs.path.join(directory, 'gradle')).listSync();
       for (FileSystemEntity entry in gradlePaths.where((FileSystemEntity e) =>
           e.basename.startsWith('gradle-') && e is Directory)) {
-        Version version =
+        final Version version =
             new Version.parse(entry.basename.substring('gradle-'.length)) ??
                 Version.unknown;
         if (latestGradleVersion == null || version > latestGradleVersion) {

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

@@ -19,15 +19,15 @@ class AndroidStudioValidator extends DoctorValidator {
   AndroidStudioValidator(this._studio) : super('Android Studio');
 
   static List<DoctorValidator> get allValidators {
-    List<DoctorValidator> validators = <DoctorValidator>[];
-    List<AndroidStudio> studios = AndroidStudio.allInstalled();
+    final List<DoctorValidator> validators = <DoctorValidator>[];
+    final List<AndroidStudio> studios = AndroidStudio.allInstalled();
     if (studios.isEmpty) {
       validators.add(new NoAndroidStudioValidator());
     } else {
       validators.addAll(studios
           .map((AndroidStudio studio) => new AndroidStudioValidator(studio)));
     }
-    String cfgGradleDir = config.getValue('gradle-dir');
+    final String cfgGradleDir = config.getValue('gradle-dir');
     if (cfgGradleDir != null) {
       validators.add(new ConfiguredGradleValidator(cfgGradleDir));
     }
@@ -36,9 +36,9 @@ class AndroidStudioValidator extends DoctorValidator {
 
   @override
   Future<ValidationResult> validate() async {
-    List<ValidationMessage> messages = <ValidationMessage>[];
+    final List<ValidationMessage> messages = <ValidationMessage>[];
     ValidationType type = ValidationType.missing;
-    String studioVersionText = 'version ${_studio.version}';
+    final String studioVersionText = 'version ${_studio.version}';
     messages
         .add(new ValidationMessage('Android Studio at ${_studio.directory}'));
     if (_studio.isValid) {
@@ -66,9 +66,9 @@ class NoAndroidStudioValidator extends DoctorValidator {
 
   @override
   Future<ValidationResult> validate() async {
-    List<ValidationMessage> messages = <ValidationMessage>[];
+    final List<ValidationMessage> messages = <ValidationMessage>[];
 
-    String cfgAndroidStudio = config.getValue('android-studio-dir');
+    final String cfgAndroidStudio = config.getValue('android-studio-dir');
     if (cfgAndroidStudio != null) {
       messages.add(
           new ValidationMessage.error('android-studio-dir = $cfgAndroidStudio\n'
@@ -91,7 +91,7 @@ class ConfiguredGradleValidator extends DoctorValidator {
   @override
   Future<ValidationResult> validate() async {
     ValidationType type = ValidationType.missing;
-    List<ValidationMessage> messages = <ValidationMessage>[];
+    final List<ValidationMessage> messages = <ValidationMessage>[];
 
     messages.add(new ValidationMessage('gradle-dir = $cfgGradleDir'));
 
@@ -103,7 +103,7 @@ class ConfiguredGradleValidator extends DoctorValidator {
     String versionString;
     if (processManager.canRun(gradleExecutable)) {
       type = ValidationType.partial;
-      ProcessResult result =
+      final ProcessResult result =
           processManager.runSync(<String>[gradleExecutable, '--version']);
       if (result.exitCode == 0) {
         versionString = result.stdout
@@ -111,7 +111,7 @@ class ConfiguredGradleValidator extends DoctorValidator {
             .split('\n')
             .firstWhere((String s) => s.startsWith('Gradle '))
             .substring('Gradle '.length);
-        Version version = new Version.parse(versionString) ?? Version.unknown;
+        final Version version = new Version.parse(versionString) ?? Version.unknown;
         if (version >= minGradleVersion) {
           type = ValidationType.installed;
         } else {

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

@@ -25,13 +25,13 @@ class AndroidWorkflow extends DoctorValidator implements Workflow {
 
   @override
   Future<ValidationResult> validate() async {
-    List<ValidationMessage> messages = <ValidationMessage>[];
+    final List<ValidationMessage> messages = <ValidationMessage>[];
     ValidationType type = ValidationType.missing;
     String sdkVersionText;
 
     if (androidSdk == null) {
       if (platform.environment.containsKey(kAndroidHome)) {
-        String androidHomeDir = platform.environment[kAndroidHome];
+        final String androidHomeDir = platform.environment[kAndroidHome];
         messages.add(new ValidationMessage.error(
           '$kAndroidHome = $androidHomeDir\n'
           'but Android SDK not found at this location.'
@@ -57,11 +57,11 @@ class AndroidWorkflow extends DoctorValidator implements Workflow {
       }
 
       if (platform.environment.containsKey(kAndroidHome)) {
-        String androidHomeDir = platform.environment[kAndroidHome];
+        final String androidHomeDir = platform.environment[kAndroidHome];
         messages.add(new ValidationMessage('$kAndroidHome = $androidHomeDir'));
       }
 
-      List<String> validationResult = androidSdk.validateSdkWellFormed();
+      final List<String> validationResult = androidSdk.validateSdkWellFormed();
 
       if (validationResult.isEmpty) {
         // Empty result means SDK is well formed.
@@ -72,10 +72,10 @@ class AndroidWorkflow extends DoctorValidator implements Workflow {
         try {
           printTrace('java -version');
 
-          ProcessResult result = processManager.runSync(<String>['java', '-version']);
+          final ProcessResult result = processManager.runSync(<String>['java', '-version']);
           if (result.exitCode == 0) {
             javaVersion = result.stderr;
-            List<String> versionLines = javaVersion.split('\n');
+            final List<String> versionLines = javaVersion.split('\n');
             javaVersion = versionLines.length >= 2 ? versionLines[1] : versionLines[0];
            }
         } catch (error) {

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

@@ -35,15 +35,15 @@ bool isProjectUsingGradle() {
 }
 
 FlutterPluginVersion get flutterPluginVersion {
-  File plugin = fs.file('android/buildSrc/src/main/groovy/FlutterPlugin.groovy');
+  final File plugin = fs.file('android/buildSrc/src/main/groovy/FlutterPlugin.groovy');
   if (plugin.existsSync()) {
-    String packageLine = plugin.readAsLinesSync().skip(4).first;
+    final String packageLine = plugin.readAsLinesSync().skip(4).first;
     if (packageLine == "package io.flutter.gradle") {
       return FlutterPluginVersion.v2;
     }
     return FlutterPluginVersion.v1;
   }
-  File appGradle = fs.file('android/app/build.gradle');
+  final File appGradle = fs.file('android/app/build.gradle');
   if (appGradle.existsSync()) {
     for (String line in appGradle.readAsLinesSync()) {
       if (line.contains(new RegExp(r"apply from: .*/flutter.gradle"))) {
@@ -69,9 +69,9 @@ String get gradleAppOut {
 }
 
 String locateSystemGradle({ bool ensureExecutable: true }) {
-  String gradle = gradleExecutable;
+  final String gradle = gradleExecutable;
   if (ensureExecutable && gradle != null) {
-    File file = fs.file(gradle);
+    final File file = fs.file(gradle);
     if (file.existsSync())
       os.makeExecutable(file);
   }
@@ -104,7 +104,7 @@ Future<String> ensureGradle() async {
 
 Future<Null> buildGradleProject(BuildMode buildMode, String target) async {
   // Create android/local.properties.
-  File localProperties = fs.file('android/local.properties');
+  final File localProperties = fs.file('android/local.properties');
   if (!localProperties.existsSync()) {
     localProperties.writeAsStringSync(
         'sdk.dir=${_escapePath(androidSdk.directory)}\n'
@@ -115,12 +115,12 @@ Future<Null> buildGradleProject(BuildMode buildMode, String target) async {
   // FlutterPlugin v1 reads local.properties to determine build mode. Plugin v2
   // uses the standard Android way to determine what to build, but we still
   // update local.properties, in case we want to use it in the future.
-  String buildModeName = getModeName(buildMode);
-  SettingsFile settings = new SettingsFile.parseFromFile(localProperties);
+  final String buildModeName = getModeName(buildMode);
+  final SettingsFile settings = new SettingsFile.parseFromFile(localProperties);
   settings.values['flutter.buildMode'] = buildModeName;
   settings.writeContents(localProperties);
 
-  String gradle = await ensureGradle();
+  final String gradle = await ensureGradle();
 
   switch (flutterPluginVersion) {
     case FlutterPluginVersion.none:
@@ -138,8 +138,8 @@ String _escapePath(String path) => platform.isWindows ? path.replaceAll('\\', '\
 
 Future<Null> buildGradleProjectV1(String gradle) async {
   // Run 'gradle build'.
-  Status status = logger.startProgress('Running \'gradle build\'...', expectSlowOperation: true);
-  int exitcode = await runCommandAndStreamOutput(
+  final Status status = logger.startProgress('Running \'gradle build\'...', expectSlowOperation: true);
+  final int exitcode = await runCommandAndStreamOutput(
     <String>[fs.file(gradle).absolute.path, 'build'],
     workingDirectory: 'android',
     allowReentrantFlutter: true
@@ -149,22 +149,22 @@ Future<Null> buildGradleProjectV1(String gradle) async {
   if (exitcode != 0)
     throwToolExit('Gradle build failed: $exitcode', exitCode: exitcode);
 
-  File apkFile = fs.file(gradleAppOutV1);
+  final File apkFile = fs.file(gradleAppOutV1);
   printStatus('Built $gradleAppOutV1 (${getSizeAsMB(apkFile.lengthSync())}).');
 }
 
 Future<Null> buildGradleProjectV2(String gradle, String buildModeName, String target) async {
-  String assembleTask = "assemble${toTitleCase(buildModeName)}";
+  final String assembleTask = "assemble${toTitleCase(buildModeName)}";
 
   // Run 'gradle assemble<BuildMode>'.
-  Status status = logger.startProgress('Running \'gradle $assembleTask\'...', expectSlowOperation: true);
-  String gradlePath = fs.file(gradle).absolute.path;
-  List<String> command = <String>[gradlePath];
+  final Status status = logger.startProgress('Running \'gradle $assembleTask\'...', expectSlowOperation: true);
+  final String gradlePath = fs.file(gradle).absolute.path;
+  final List<String> command = <String>[gradlePath];
   if (!logger.isVerbose) {
     command.add('-q');
   }
   if (artifacts is LocalEngineArtifacts) {
-    LocalEngineArtifacts localEngineArtifacts = artifacts;
+    final LocalEngineArtifacts localEngineArtifacts = artifacts;
     printTrace('Using local engine: ${localEngineArtifacts.engineOutPath}');
     command.add('-PlocalEngineOut=${localEngineArtifacts.engineOutPath}');
   }
@@ -172,7 +172,7 @@ Future<Null> buildGradleProjectV2(String gradle, String buildModeName, String ta
     command.add('-Ptarget=$target');
   }
   command.add(assembleTask);
-  int exitcode = await runCommandAndStreamOutput(
+  final int exitcode = await runCommandAndStreamOutput(
       command,
       workingDirectory: 'android',
       allowReentrantFlutter: true
@@ -182,13 +182,13 @@ Future<Null> buildGradleProjectV2(String gradle, String buildModeName, String ta
   if (exitcode != 0)
     throwToolExit('Gradle build failed: $exitcode', exitCode: exitcode);
 
-  String apkFilename = 'app-$buildModeName.apk';
-  File apkFile = fs.file('$gradleAppOutDir/$apkFilename');
+  final String apkFilename = 'app-$buildModeName.apk';
+  final File apkFile = fs.file('$gradleAppOutDir/$apkFilename');
   // Copy the APK to app.apk, so `flutter run`, `flutter install`, etc. can find it.
   apkFile.copySync('$gradleAppOutDir/app.apk');
 
   printTrace('calculateSha: $gradleAppOutDir/app.apk');
-  File apkShaFile = fs.file('$gradleAppOutDir/app.apk.sha1');
+  final File apkShaFile = fs.file('$gradleAppOutDir/app.apk.sha1');
   apkShaFile.writeAsStringSync(calculateSha(apkFile));
 
   printStatus('Built $apkFilename (${getSizeAsMB(apkFile.lengthSync())}).');

packages/flutter_tools/lib/src/application_package.dart

@@ -50,14 +50,14 @@ class AndroidApk extends ApplicationPackage {
 
   /// Creates a new AndroidApk from an existing APK.
   factory AndroidApk.fromApk(String applicationBinary) {
-    String aaptPath = androidSdk?.latestVersion?.aaptPath;
+    final String aaptPath = androidSdk?.latestVersion?.aaptPath;
     if (aaptPath == null) {
       printError('Unable to locate the Android SDK; please run \'flutter doctor\'.');
       return null;
     }
 
-    List<String> aaptArgs = <String>[aaptPath, 'dump', 'badging', applicationBinary];
-    ApkManifestData data = ApkManifestData.parseFromAaptBadging(runCheckedSync(aaptArgs));
+    final List<String> aaptArgs = <String>[aaptPath, 'dump', 'badging', applicationBinary];
+    final ApkManifestData data = ApkManifestData.parseFromAaptBadging(runCheckedSync(aaptArgs));
 
     if (data == null) {
       printError('Unable to read manifest info from $applicationBinary.');
@@ -100,19 +100,19 @@ class AndroidApk extends ApplicationPackage {
     if (!fs.isFileSync(manifestPath))
       return null;
 
-    String manifestString = fs.file(manifestPath).readAsStringSync();
-    xml.XmlDocument document = xml.parse(manifestString);
+    final String manifestString = fs.file(manifestPath).readAsStringSync();
+    final xml.XmlDocument document = xml.parse(manifestString);
 
-    Iterable<xml.XmlElement> manifests = document.findElements('manifest');
+    final Iterable<xml.XmlElement> manifests = document.findElements('manifest');
     if (manifests.isEmpty)
       return null;
-    String packageId = manifests.first.getAttribute('package');
+    final String packageId = manifests.first.getAttribute('package');
 
     String launchActivity;
     for (xml.XmlElement category in document.findAllElements('category')) {
       if (category.getAttribute('android:name') == 'android.intent.category.LAUNCHER') {
-        xml.XmlElement activity = category.parent.parent;
-        String activityName = activity.getAttribute('android:name');
+        final xml.XmlElement activity = category.parent.parent;
+        final String activityName = activity.getAttribute('android:name');
         launchActivity = "$packageId/$activityName";
         break;
       }
@@ -146,18 +146,18 @@ abstract class IOSApp extends ApplicationPackage {
   factory IOSApp.fromIpa(String applicationBinary) {
     Directory bundleDir;
     try {
-      Directory tempDir = fs.systemTempDirectory.createTempSync('flutter_app_');
+      final Directory tempDir = fs.systemTempDirectory.createTempSync('flutter_app_');
       addShutdownHook(() async => await tempDir.delete(recursive: true));
       os.unzip(fs.file(applicationBinary), tempDir);
-      Directory payloadDir = fs.directory(fs.path.join(tempDir.path, 'Payload'));
+      final Directory payloadDir = fs.directory(fs.path.join(tempDir.path, 'Payload'));
       bundleDir = payloadDir.listSync().singleWhere(_isBundleDirectory);
     } on StateError catch (e, stackTrace) {
       printError('Invalid prebuilt iOS binary: ${e.toString()}', stackTrace);
       return null;
     }
 
-    String plistPath = fs.path.join(bundleDir.path, 'Info.plist');
-    String id = plist.getValueFromFile(plistPath, plist.kCFBundleIdentifierKey);
+    final String plistPath = fs.path.join(bundleDir.path, 'Info.plist');
+    final String id = plist.getValueFromFile(plistPath, plist.kCFBundleIdentifierKey);
     if (id == null)
       return null;
 
@@ -173,11 +173,11 @@ abstract class IOSApp extends ApplicationPackage {
     if (getCurrentHostPlatform() != HostPlatform.darwin_x64)
       return null;
 
-    String plistPath = fs.path.join('ios', 'Runner', 'Info.plist');
+    final String plistPath = fs.path.join('ios', 'Runner', 'Info.plist');
     String id = plist.getValueFromFile(plistPath, plist.kCFBundleIdentifierKey);
     if (id == null)
       return null;
-    String projectPath = fs.path.join('ios', 'Runner.xcodeproj');
+    final String projectPath = fs.path.join('ios', 'Runner.xcodeproj');
     id = substituteXcodeVariables(id, projectPath, 'Runner');
 
     return new BuildableIOSApp(
@@ -299,22 +299,22 @@ class ApkManifestData {
 
     // package: name='io.flutter.gallery' versionCode='1' versionName='0.0.1' platformBuildVersionName='NMR1'
     // launchable-activity: name='io.flutter.app.FlutterActivity'  label='' icon=''
-    Map<String, Map<String, String>> map = <String, Map<String, String>>{};
+    final Map<String, Map<String, String>> map = <String, Map<String, String>>{};
 
     for (String line in data.split('\n')) {
-      int index = line.indexOf(':');
+      final int index = line.indexOf(':');
       if (index != -1) {
-        String name = line.substring(0, index);
+        final String name = line.substring(0, index);
         line = line.substring(index + 1).trim();
 
-        Map<String, String> entries = <String, String>{};
+        final Map<String, String> entries = <String, String>{};
         map[name] = entries;
 
         for (String entry in line.split(' ')) {
           entry = entry.trim();
           if (entry.isNotEmpty && entry.contains('=')) {
-            int split = entry.indexOf('=');
-            String key = entry.substring(0, split);
+            final int split = entry.indexOf('=');
+            final String key = entry.substring(0, split);
             String value = entry.substring(split + 1);
             if (value.startsWith("'") && value.endsWith("'"))
               value = value.substring(1, value.length - 1);

packages/flutter_tools/lib/src/artifacts.dart

@@ -105,7 +105,7 @@ class CachedArtifacts extends Artifacts {
   }
 
   String _getAndroidArtifactPath(Artifact artifact, TargetPlatform platform, BuildMode mode) {
-    String engineDir = _getEngineArtifactsPath(platform, mode);
+    final String engineDir = _getEngineArtifactsPath(platform, mode);
     switch (artifact) {
       case Artifact.chromiumDebugKeyStore:
       case Artifact.classesDexJar:
@@ -119,7 +119,7 @@ class CachedArtifacts extends Artifacts {
         return fs.path.join(engineDir, _artifactToFileName(artifact));
       case Artifact.genSnapshot:
         assert(mode != BuildMode.debug, 'Artifact $artifact only available in non-debug mode.');
-        String hostPlatform = getNameForHostPlatform(getCurrentHostPlatform());
+        final String hostPlatform = getNameForHostPlatform(getCurrentHostPlatform());
         return fs.path.join(engineDir, hostPlatform, _artifactToFileName(artifact));
       default:
         assert(false, 'Artifact $artifact not available for platform $platform.');
@@ -128,7 +128,7 @@ class CachedArtifacts extends Artifacts {
   }
 
   String _getIosArtifactPath(Artifact artifact, TargetPlatform platform, BuildMode mode) {
-    String engineDir = _getEngineArtifactsPath(platform, mode);
+    final String engineDir = _getEngineArtifactsPath(platform, mode);
     switch (artifact) {
       case Artifact.dartIoEntriesTxt:
       case Artifact.dartVmEntryPointsTxt:
@@ -157,8 +157,8 @@ class CachedArtifacts extends Artifacts {
         continue returnResourcePath;
       returnResourcePath:
       case Artifact.icudtlDat:
-        String engineArtifactsPath = cache.getArtifactDirectory('engine').path;
-        String platformDirName = getNameForTargetPlatform(platform);
+        final String engineArtifactsPath = cache.getArtifactDirectory('engine').path;
+        final String platformDirName = getNameForTargetPlatform(platform);
         return fs.path.join(engineArtifactsPath, platformDirName, _artifactToFileName(artifact));
       default:
         assert(false, 'Artifact $artifact not available for platform $platform.');
@@ -169,8 +169,8 @@ class CachedArtifacts extends Artifacts {
   }
 
   String _getEngineArtifactsPath(TargetPlatform platform, [BuildMode mode]) {
-    String engineDir = cache.getArtifactDirectory('engine').path;
-    String platformName = getNameForTargetPlatform(platform);
+    final String engineDir = cache.getArtifactDirectory('engine').path;
+    final String platformName = getNameForTargetPlatform(platform);
     switch (platform) {
       case TargetPlatform.linux_x64:
       case TargetPlatform.darwin_x64:
@@ -182,7 +182,7 @@ class CachedArtifacts extends Artifacts {
       case TargetPlatform.android_x64:
       case TargetPlatform.android_x86:
         assert(mode != null, 'Need to specify a build mode for platform $platform.');
-        String suffix = mode != BuildMode.debug ? '-${getModeName(mode)}' : '';
+        final String suffix = mode != BuildMode.debug ? '-${getModeName(mode)}' : '';
         return fs.path.join(engineDir, platformName + suffix);
     }
     assert(false, 'Invalid platform $platform.');
@@ -222,7 +222,7 @@ class LocalEngineArtifacts extends Artifacts {
       case Artifact.classesDexJar:
         return fs.path.join(engineOutPath, 'gen', 'flutter', 'shell', 'platform', 'android', 'android', _artifactToFileName(artifact));
       case Artifact.libskyShellSo:
-        String abi = _getAbiDirectory(platform);
+        final String abi = _getAbiDirectory(platform);
         return fs.path.join(engineOutPath, 'gen', 'flutter', 'shell', 'platform', 'android', 'android', fs.path.join('android', 'libs', abi, _artifactToFileName(artifact)));
       case Artifact.genSnapshot:
         return _genSnapshotPath(platform);
@@ -257,7 +257,7 @@ class LocalEngineArtifacts extends Artifacts {
   }
 
   String _skySnapshotPath() {
-    String clangPath = fs.path.join(engineOutPath, 'clang_x64', _artifactToFileName(Artifact.skySnapshot));
+    final String clangPath = fs.path.join(engineOutPath, 'clang_x64', _artifactToFileName(Artifact.skySnapshot));
     if (fs.isFileSync(clangPath))
       return clangPath;
     return fs.path.join(engineOutPath, _artifactToFileName(Artifact.skySnapshot));

packages/flutter_tools/lib/src/asset.dart

@@ -41,7 +41,7 @@ class AssetBundle {
     if ((projectRoot == null) || (projectAssets == null))
       return;
 
-    List<String> assets = projectAssets.split(',');
+    final List<String> assets = projectAssets.split(',');
     for (String asset in assets) {
       if (asset == '')
         continue;
@@ -57,7 +57,7 @@ class AssetBundle {
     if (_lastBuildTimestamp == null)
       return true;
 
-    FileStat stat = fs.file(manifestPath).statSync();
+    final FileStat stat = fs.file(manifestPath).statSync();
     if (stat.type == FileSystemEntityType.NOT_FOUND)
       return true;
 
@@ -88,19 +88,19 @@ class AssetBundle {
       return 0;
     }
     if (manifest != null) {
-     int result = await _validateFlutterManifest(manifest);
+     final int result = await _validateFlutterManifest(manifest);
      if (result != 0)
        return result;
     }
     Map<String, dynamic> manifestDescriptor = manifest;
     manifestDescriptor = manifestDescriptor['flutter'] ?? <String, dynamic>{};
-    String assetBasePath = fs.path.dirname(fs.path.absolute(manifestPath));
+    final String assetBasePath = fs.path.dirname(fs.path.absolute(manifestPath));
 
     _lastBuildTimestamp = new DateTime.now();
 
     final PackageMap packageMap = new PackageMap(packagesPath);
 
-    Map<_Asset, List<_Asset>> assetVariants = _parseAssets(
+    final Map<_Asset, List<_Asset>> assetVariants = _parseAssets(
       packageMap,
       manifestDescriptor,
       assetBasePath,
@@ -123,7 +123,7 @@ class AssetBundle {
       }
     }
 
-    List<_Asset> materialAssets = <_Asset>[];
+    final List<_Asset> materialAssets = <_Asset>[];
     if (usesMaterialDesign && includeDefaultFonts) {
       materialAssets.addAll(_getMaterialAssets(_kFontSetMaterial));
       if (includeRobotoFonts)
@@ -136,7 +136,7 @@ class AssetBundle {
 
     entries[_kAssetManifestJson] = _createAssetManifest(assetVariants);
 
-    DevFSContent fontManifest =
+    final DevFSContent fontManifest =
         _createFontManifest(manifestDescriptor, usesMaterialDesign, includeDefaultFonts, includeRobotoFonts);
     if (fontManifest != null)
       entries[_kFontManifestJson] = fontManifest;
@@ -183,7 +183,7 @@ class _Asset {
   String get symbolicPrefix {
     if (_assetEntry == null || _assetEntry == relativePath)
       return null;
-    int index = _assetEntry.indexOf(relativePath);
+    final int index = _assetEntry.indexOf(relativePath);
     return index == -1 ? null : _assetEntry.substring(0, index);
   }
 
@@ -192,7 +192,7 @@ class _Asset {
 }
 
 Map<String, dynamic> _readMaterialFontsManifest() {
-  String fontsPath = fs.path.join(fs.path.absolute(Cache.flutterRoot),
+  final String fontsPath = fs.path.join(fs.path.absolute(Cache.flutterRoot),
       'packages', 'flutter_tools', 'schema', 'material_fonts.yaml');
 
   return loadYaml(fs.file(fontsPath).readAsStringSync());
@@ -205,11 +205,11 @@ List<Map<String, dynamic>> _getMaterialFonts(String fontSet) {
 }
 
 List<_Asset> _getMaterialAssets(String fontSet) {
-  List<_Asset> result = <_Asset>[];
+  final List<_Asset> result = <_Asset>[];
 
   for (Map<String, dynamic> family in _getMaterialFonts(fontSet)) {
     for (Map<String, dynamic> font in family['fonts']) {
-      String assetKey = font['asset'];
+      final String assetKey = font['asset'];
       result.add(new _Asset(
         base: fs.path.join(Cache.flutterRoot, 'bin', 'cache', 'artifacts', 'material_fonts'),
         source: fs.path.basename(assetKey),
@@ -281,7 +281,7 @@ Future<DevFSContent> _obtainLicenses(
 
   final List<String> combinedLicensesList = packageLicenses.keys.map(
     (String license) {
-      List<String> packageNames = packageLicenses[license].toList()
+      final List<String> packageNames = packageLicenses[license].toList()
        ..sort();
       return packageNames.join('\n') + '\n\n' + license;
     }
@@ -294,9 +294,9 @@ Future<DevFSContent> _obtainLicenses(
 }
 
 DevFSContent _createAssetManifest(Map<_Asset, List<_Asset>> assetVariants) {
-  Map<String, List<String>> json = <String, List<String>>{};
+  final Map<String, List<String>> json = <String, List<String>>{};
   for (_Asset main in assetVariants.keys) {
-    List<String> variants = <String>[];
+    final List<String> variants = <String>[];
     for (_Asset variant in assetVariants[main])
       variants.add(variant.relativePath);
     json[main.relativePath] = variants;
@@ -308,7 +308,7 @@ DevFSContent _createFontManifest(Map<String, dynamic> manifestDescriptor,
                              bool usesMaterialDesign,
                              bool includeDefaultFonts,
                              bool includeRobotoFonts) {
-  List<Map<String, dynamic>> fonts = <Map<String, dynamic>>[];
+  final List<Map<String, dynamic>> fonts = <Map<String, dynamic>>[];
   if (usesMaterialDesign && includeDefaultFonts) {
     fonts.addAll(_getMaterialFonts(AssetBundle._kFontSetMaterial));
     if (includeRobotoFonts)
@@ -331,7 +331,7 @@ Map<_Asset, List<_Asset>> _parseAssets(
   String assetBase, {
   List<String> excludeDirs: const <String>[]
 }) {
-  Map<_Asset, List<_Asset>> result = <_Asset, List<_Asset>>{};
+  final Map<_Asset, List<_Asset>> result = <_Asset, List<_Asset>>{};
 
   if (manifestDescriptor == null)
     return result;
@@ -342,22 +342,22 @@ Map<_Asset, List<_Asset>> _parseAssets(
 
   if (manifestDescriptor.containsKey('assets')) {
     for (String asset in manifestDescriptor['assets']) {
-      _Asset baseAsset = _resolveAsset(packageMap, assetBase, asset);
+      final _Asset baseAsset = _resolveAsset(packageMap, assetBase, asset);
 
       if (!baseAsset.assetFileExists) {
         printError('Error: unable to locate asset entry in pubspec.yaml: "$asset".');
         return null;
       }
 
-      List<_Asset> variants = <_Asset>[];
+      final List<_Asset> variants = <_Asset>[];
       result[baseAsset] = variants;
 
       // Find asset variants
-      String assetPath = baseAsset.assetFile.path;
-      String assetFilename = fs.path.basename(assetPath);
-      Directory assetDir = fs.directory(fs.path.dirname(assetPath));
+      final String assetPath = baseAsset.assetFile.path;
+      final String assetFilename = fs.path.basename(assetPath);
+      final Directory assetDir = fs.directory(fs.path.dirname(assetPath));
 
-      List<FileSystemEntity> files = assetDir.listSync(recursive: true);
+      final List<FileSystemEntity> files = assetDir.listSync(recursive: true);
 
       for (FileSystemEntity entity in files) {
         if (!fs.isFileSync(entity.path))
@@ -368,7 +368,7 @@ Map<_Asset, List<_Asset>> _parseAssets(
           continue;
 
         if (fs.path.basename(entity.path) == assetFilename && entity.path != assetPath) {
-          String key = fs.path.relative(entity.path, from: baseAsset.base);
+          final String key = fs.path.relative(entity.path, from: baseAsset.base);
           String assetEntry;
           if (baseAsset.symbolicPrefix != null)
             assetEntry = fs.path.join(baseAsset.symbolicPrefix, key);
@@ -381,14 +381,14 @@ Map<_Asset, List<_Asset>> _parseAssets(
   // Add assets referenced in the fonts section of the manifest.
   if (manifestDescriptor.containsKey('fonts')) {
     for (Map<String, dynamic> family in manifestDescriptor['fonts']) {
-      List<Map<String, dynamic>> fonts = family['fonts'];
+      final List<Map<String, dynamic>> fonts = family['fonts'];
       if (fonts == null) continue;
 
       for (Map<String, dynamic> font in fonts) {
-        String asset = font['asset'];
+        final String asset = font['asset'];
         if (asset == null) continue;
 
-        _Asset baseAsset = _resolveAsset(packageMap, assetBase, asset);
+        final _Asset baseAsset = _resolveAsset(packageMap, assetBase, asset);
         if (!baseAsset.assetFileExists) {
           printError('Error: unable to locate asset entry in pubspec.yaml: "$asset".');
           return null;
@@ -412,15 +412,15 @@ _Asset _resolveAsset(
     String packageKey = asset.substring(9);
     String relativeAsset = asset;
 
-    int index = packageKey.indexOf('/');
+    final int index = packageKey.indexOf('/');
     if (index != -1) {
       relativeAsset = packageKey.substring(index + 1);
       packageKey = packageKey.substring(0, index);
     }
 
-    Uri uri = packageMap.map[packageKey];
+    final Uri uri = packageMap.map[packageKey];
     if (uri != null && uri.scheme == 'file') {
-      File file = fs.file(uri);
+      final File file = fs.file(uri);
       return new _Asset(base: file.path, assetEntry: asset, relativePath: relativeAsset);
     }
   }
@@ -431,16 +431,16 @@ _Asset _resolveAsset(
 dynamic _loadFlutterManifest(String manifestPath) {
   if (manifestPath == null || !fs.isFileSync(manifestPath))
     return null;
-  String manifestDescriptor = fs.file(manifestPath).readAsStringSync();
+  final String manifestDescriptor = fs.file(manifestPath).readAsStringSync();
   return loadYaml(manifestDescriptor);
 }
 
 Future<int> _validateFlutterManifest(Object manifest) async {
-  String schemaPath = fs.path.join(fs.path.absolute(Cache.flutterRoot),
+  final String schemaPath = fs.path.join(fs.path.absolute(Cache.flutterRoot),
       'packages', 'flutter_tools', 'schema', 'pubspec_yaml.json');
-  Schema schema = await Schema.createSchemaFromUrl(fs.path.toUri(schemaPath).toString());
+  final Schema schema = await Schema.createSchemaFromUrl(fs.path.toUri(schemaPath).toString());
 
-  Validator validator = new Validator(schema);
+  final Validator validator = new Validator(schema);
   if (validator.validate(manifest)) {
     return 0;
   } else {

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

@@ -44,7 +44,7 @@ class Config {
 }
 
 String _userHomeDir() {
-  String envKey = platform.operatingSystem == 'windows' ? 'APPDATA' : 'HOME';
-  String value = platform.environment[envKey];
+  final String envKey = platform.operatingSystem == 'windows' ? 'APPDATA' : 'HOME';
+  final String value = platform.environment[envKey];
   return value == null ? '.' : value;
 }

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

@@ -20,7 +20,7 @@ class AppContext {
     if (_instances.containsKey(type))
       return true;
 
-    AppContext parent = _calcParent(_zone);
+    final AppContext parent = _calcParent(_zone);
     return parent != null ? parent.isSet(type) : false;
   }
 
@@ -28,7 +28,7 @@ class AppContext {
     if (_instances.containsKey(type))
       return _instances[type];
 
-    AppContext parent = _calcParent(_zone);
+    final AppContext parent = _calcParent(_zone);
     return parent?.getVariable(type);
   }
 
@@ -49,11 +49,11 @@ class AppContext {
   }
 
   AppContext _calcParent(Zone zone) {
-    Zone parentZone = zone.parent;
+    final Zone parentZone = zone.parent;
     if (parentZone == null)
       return null;
 
-    AppContext parentContext = parentZone['context'];
+    final AppContext parentContext = parentZone['context'];
     return parentContext == this
         ? _calcParent(parentZone)
         : parentContext;
@@ -70,7 +70,7 @@ class AppContext {
   }
 
   Future<dynamic> _run(dynamic method()) async {
-    Zone previousZone = _zone;
+    final Zone previousZone = _zone;
     try {
       _zone = Zone.current;
       return await method();

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

@@ -34,9 +34,9 @@ FileSystem get fs => context == null ? _kLocalFs : context[FileSystem];
 /// It is permissible for [location] to represent an existing non-empty
 /// directory as long as there is no collision with the `"file"` subdirectory.
 void enableRecordingFileSystem(String location) {
-  FileSystem originalFileSystem = fs;
-  Directory dir = getRecordingSink(location, _kRecordingType);
-  RecordingFileSystem fileSystem = new RecordingFileSystem(
+  final FileSystem originalFileSystem = fs;
+  final Directory dir = getRecordingSink(location, _kRecordingType);
+  final RecordingFileSystem fileSystem = new RecordingFileSystem(
       delegate: _kLocalFs, destination: dir);
   addShutdownHook(() async {
     await fileSystem.recording.flush();
@@ -54,13 +54,13 @@ void enableRecordingFileSystem(String location) {
 /// been recorded (i.e. the result of having been previously passed to
 /// [enableRecordingFileSystem]), or a [ToolExit] will be thrown.
 void enableReplayFileSystem(String location) {
-  Directory dir = getReplaySource(location, _kRecordingType);
+  final Directory dir = getReplaySource(location, _kRecordingType);
   context.setVariable(FileSystem, new ReplayFileSystem(recording: dir));
 }
 
 /// Create the ancestor directories of a file path if they do not already exist.
 void ensureDirectoryExists(String filePath) {
-  String dirPath = fs.path.dirname(filePath);
+  final String dirPath = fs.path.dirname(filePath);
   if (fs.isDirectorySync(dirPath))
     return;
   try {
@@ -81,9 +81,9 @@ void copyDirectorySync(Directory srcDir, Directory destDir) {
     destDir.createSync(recursive: true);
 
   srcDir.listSync().forEach((FileSystemEntity entity) {
-    String newPath = destDir.fileSystem.path.join(destDir.path, entity.basename);
+    final String newPath = destDir.fileSystem.path.join(destDir.path, entity.basename);
     if (entity is File) {
-      File newFile = destDir.fileSystem.file(newPath);
+      final File newFile = destDir.fileSystem.file(newPath);
       newFile.writeAsBytesSync(entity.readAsBytesSync());
     } else if (entity is Directory) {
       copyDirectorySync(
@@ -105,7 +105,7 @@ void copyDirectorySync(Directory srcDir, Directory destDir) {
 /// directory exists as an entity other than a directory, a [ToolExit] will
 /// also be thrown.
 Directory getRecordingSink(String dirname, String basename) {
-  String location = _kLocalFs.path.join(dirname, basename);
+  final String location = _kLocalFs.path.join(dirname, basename);
   switch (_kLocalFs.typeSync(location, followLinks: false)) {
     case FileSystemEntityType.FILE:
     case FileSystemEntityType.LINK:
@@ -129,7 +129,7 @@ Directory getRecordingSink(String dirname, String basename) {
 ///
 /// If the target directory does not exist, a [ToolExit] will be thrown.
 Directory getReplaySource(String dirname, String basename) {
-  Directory dir = _kLocalFs.directory(_kLocalFs.path.join(dirname, basename));
+  final Directory dir = _kLocalFs.directory(_kLocalFs.path.join(dirname, basename));
   if (!dir.existsSync())
     throwToolExit('Invalid replay-from location: $dirname ("$basename" does not exist)');
   return dir;

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

@@ -206,7 +206,7 @@ class VerboseLogger extends Logger {
     if (message.trim().isEmpty)
       return;
 
-    int millis = stopwatch.elapsedMilliseconds;
+    final int millis = stopwatch.elapsedMilliseconds;
     stopwatch.reset();
 
     String prefix;
@@ -220,8 +220,8 @@ class VerboseLogger extends Logger {
     }
     prefix = '[$prefix] ';
 
-    String indent = ''.padLeft(prefix.length);
-    String indentMessage = message.replaceAll('\n', '\n$indent');
+    final String indent = ''.padLeft(prefix.length);
+    final String indentMessage = message.replaceAll('\n', '\n$indent');
 
     if (type == _LogType.error) {
       stderr.writeln(prefix + terminal.bolden(indentMessage));
@@ -243,9 +243,9 @@ enum _LogType {
 
 class AnsiTerminal {
   AnsiTerminal() {
-    String term = platform.environment['TERM'];
+    final String term = platform.environment['TERM'];
     // FLUTTER_ANSI_TERMINAL is a work-around for https://github.com/dart-lang/sdk/issues/28614
-    bool flutterAnsiTerm = platform.environment.containsKey('FLUTTER_ANSI_TERMINAL');
+    final bool flutterAnsiTerm = platform.environment.containsKey('FLUTTER_ANSI_TERMINAL');
     supportsColor = (term != null && term != 'dumb') || flutterAnsiTerm;
   }
 
@@ -326,7 +326,7 @@ class _AnsiStatus extends Status {
     live = false;
 
     if (expectSlowOperation) {
-      double seconds = stopwatch.elapsedMilliseconds / Duration.MILLISECONDS_PER_SECOND;
+      final double seconds = stopwatch.elapsedMilliseconds / Duration.MILLISECONDS_PER_SECOND;
       print('\b\b\b\b\b${secondsFormat.format(seconds).padLeft(4)}s');
     } else {
       print('\b\b\b\b\b${millisecondsFormat.format(stopwatch.elapsedMilliseconds).padLeft(3)}ms');

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

@@ -14,9 +14,9 @@ const int kNetworkProblemExitCode = 50;
 Future<List<int>> fetchUrl(Uri url) async {
   printTrace('Downloading $url.');
 
-  HttpClient httpClient = new HttpClient();
-  HttpClientRequest request = await httpClient.getUrl(url);
-  HttpClientResponse response = await request.close();
+  final HttpClient httpClient = new HttpClient();
+  final HttpClientRequest request = await httpClient.getUrl(url);
+  final HttpClientResponse response = await request.close();
 
   printTrace('Received response statusCode=${response.statusCode}');
   if (response.statusCode != 200) {
@@ -28,7 +28,7 @@ Future<List<int>> fetchUrl(Uri url) async {
   }
 
   try {
-    BytesBuilder responseBody = new BytesBuilder(copy: false);
+    final BytesBuilder responseBody = new BytesBuilder(copy: false);
     await for (List<int> chunk in response)
         responseBody.add(chunk);
 

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

@@ -54,10 +54,10 @@ class _PosixUtils extends OperatingSystemUtils {
   /// to locate the binary.
   @override
   File which(String execName) {
-    ProcessResult result = processManager.runSync(<String>['which', execName]);
+    final ProcessResult result = processManager.runSync(<String>['which', execName]);
     if (result.exitCode != 0)
       return null;
-    String path = result.stdout.trim().split('\n').first.trim();
+    final String path = result.stdout.trim().split('\n').first.trim();
     return fs.file(path);
   }
 
@@ -90,7 +90,7 @@ class _WindowsUtils extends OperatingSystemUtils {
 
   @override
   File which(String execName) {
-    ProcessResult result = processManager.runSync(<String>['where', execName]);
+    final ProcessResult result = processManager.runSync(<String>['where', execName]);
     if (result.exitCode != 0)
       return null;
     return fs.file(result.stdout.trim().split('\n').first.trim());
@@ -98,14 +98,14 @@ class _WindowsUtils extends OperatingSystemUtils {
 
   @override
   void zip(Directory data, File zipFile) {
-    Archive archive = new Archive();
+    final Archive archive = new Archive();
     for (FileSystemEntity entity in data.listSync(recursive: true)) {
       if (entity is! File) {
         continue;
       }
-      File file = entity;
-      String path = file.fileSystem.path.relative(file.path, from: data.path);
-      List<int> bytes = file.readAsBytesSync();
+      final File file = entity;
+      final String path = file.fileSystem.path.relative(file.path, from: data.path);
+      final List<int> bytes = file.readAsBytesSync();
       archive.addFile(new ArchiveFile(path, bytes.length, bytes));
     }
     zipFile.writeAsBytesSync(new ZipEncoder().encode(archive), flush: true);
@@ -113,14 +113,14 @@ class _WindowsUtils extends OperatingSystemUtils {
 
   @override
   void unzip(File file, Directory targetDirectory) {
-    Archive archive = new ZipDecoder().decodeBytes(file.readAsBytesSync());
+    final Archive archive = new ZipDecoder().decodeBytes(file.readAsBytesSync());
 
     for (ArchiveFile archiveFile in archive.files) {
       // The archive package doesn't correctly set isFile.
       if (!archiveFile.isFile || archiveFile.name.endsWith('/'))
         continue;
 
-      File destFile = fs.file(fs.path.join(targetDirectory.path, archiveFile.name));
+      final File destFile = fs.file(fs.path.join(targetDirectory.path, archiveFile.name));
       if (!destFile.parent.existsSync())
         destFile.parent.createSync(recursive: true);
       destFile.writeAsBytesSync(archiveFile.content);
@@ -134,8 +134,8 @@ class _WindowsUtils extends OperatingSystemUtils {
 }
 
 Future<int> findAvailablePort() async {
-  ServerSocket socket = await ServerSocket.bind(InternetAddress.LOOPBACK_IP_V4, 0);
-  int port = socket.port;
+  final ServerSocket socket = await ServerSocket.bind(InternetAddress.LOOPBACK_IP_V4, 0);
+  final int port = socket.port;
   await socket.close();
   return port;
 }
@@ -148,7 +148,7 @@ Future<int> findPreferredPort(int defaultPort, { int searchStep: 2 }) async {
   int iterationCount = 0;
 
   while (iterationCount < _kMaxSearchIterations) {
-    int port = defaultPort + iterationCount * searchStep;
+    final int port = defaultPort + iterationCount * searchStep;
     if (await _isPortAvailable(port))
       return port;
     iterationCount++;
@@ -160,7 +160,7 @@ Future<int> findPreferredPort(int defaultPort, { int searchStep: 2 }) async {
 Future<bool> _isPortAvailable(int port) async {
   try {
     // TODO(ianh): This is super racy.
-    ServerSocket socket = await ServerSocket.bind(InternetAddress.LOOPBACK_IP_V4, port);
+    final ServerSocket socket = await ServerSocket.bind(InternetAddress.LOOPBACK_IP_V4, port);
     await socket.close();
     return true;
   } catch (error) {
@@ -178,7 +178,7 @@ String findProjectRoot([String directory]) {
   while (true) {
     if (fs.isFileSync(fs.path.join(directory, kProjectRootSentinel)))
       return directory;
-    String parent = fs.path.dirname(directory);
+    final String parent = fs.path.dirname(directory);
     if (directory == parent) return null;
     directory = parent;
   }

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

@@ -24,19 +24,19 @@ Platform get platform => context == null ? _kLocalPlatform : context[Platform];
 /// non-empty directory as long as there is no collision with the `"platform"`
 /// subdirectory.
 Future<Null> enableRecordingPlatform(String location) async {
-  Directory dir = getRecordingSink(location, _kRecordingType);
-  File file = _getPlatformManifest(dir);
+  final Directory dir = getRecordingSink(location, _kRecordingType);
+  final File file = _getPlatformManifest(dir);
   await file.writeAsString(platform.toJson(), flush: true);
 }
 
 Future<Null> enableReplayPlatform(String location) async {
-  Directory dir = getReplaySource(location, _kRecordingType);
-  File file = _getPlatformManifest(dir);
-  String json = await file.readAsString();
+  final Directory dir = getReplaySource(location, _kRecordingType);
+  final File file = _getPlatformManifest(dir);
+  final String json = await file.readAsString();
   context.setVariable(Platform, new FakePlatform.fromJson(json));
 }
 
 File _getPlatformManifest(Directory dir) {
-  String path = dir.fileSystem.path.join(dir.path, 'MANIFEST.txt');
+  final String path = dir.fileSystem.path.join(dir.path, 'MANIFEST.txt');
   return dir.fileSystem.file(path);
 }

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

@@ -69,8 +69,8 @@ Future<Null> runShutdownHooks() async {
   _shutdownHooksRunning = true;
   try {
     for (ShutdownStage stage in _shutdownHooks.keys.toList()..sort()) {
-      List<ShutdownHook> hooks = _shutdownHooks.remove(stage);
-      List<Future<dynamic>> futures = <Future<dynamic>>[];
+      final List<ShutdownHook> hooks = _shutdownHooks.remove(stage);
+      final List<Future<dynamic>> futures = <Future<dynamic>>[];
       for (ShutdownHook shutdownHook in hooks)
         futures.add(shutdownHook());
       await Future.wait<dynamic>(futures);
@@ -100,7 +100,7 @@ Future<Process> runCommand(List<String> cmd, {
   Map<String, String> environment
 }) async {
   _traceCommand(cmd, workingDirectory: workingDirectory);
-  Process process = await processManager.start(
+  final Process process = await processManager.start(
     cmd,
     workingDirectory: workingDirectory,
     environment: _environment(allowReentrantFlutter, environment)
@@ -119,13 +119,13 @@ Future<int> runCommandAndStreamOutput(List<String> cmd, {
   StringConverter mapFunction,
   Map<String, String> environment
 }) async {
-  Process process = await runCommand(
+  final Process process = await runCommand(
     cmd,
     workingDirectory: workingDirectory,
     allowReentrantFlutter: allowReentrantFlutter,
     environment: environment
   );
-  StreamSubscription<String> subscription = process.stdout
+  final StreamSubscription<String> subscription = process.stdout
     .transform(UTF8.decoder)
     .transform(const LineSplitter())
     .where((String line) => filter == null ? true : filter.hasMatch(line))
@@ -133,7 +133,7 @@ Future<int> runCommandAndStreamOutput(List<String> cmd, {
       if (mapFunction != null)
         line = mapFunction(line);
       if (line != null) {
-        String message = '$prefix$line';
+        final String message = '$prefix$line';
         if (trace)
           printTrace(message);
         else
@@ -160,7 +160,7 @@ Future<int> runCommandAndStreamOutput(List<String> cmd, {
 }
 
 Future<Null> runAndKill(List<String> cmd, Duration timeout) {
-  Future<Process> proc = runDetached(cmd);
+  final Future<Process> proc = runDetached(cmd);
   return new Future<Null>.delayed(timeout, () async {
     printTrace('Intentionally killing ${cmd[0]}');
     processManager.killPid((await proc).pid);
@@ -169,7 +169,7 @@ Future<Null> runAndKill(List<String> cmd, Duration timeout) {
 
 Future<Process> runDetached(List<String> cmd) {
   _traceCommand(cmd);
-  Future<Process> proc = processManager.start(
+  final Future<Process> proc = processManager.start(
     cmd,
     mode: ProcessStartMode.DETACHED,
   );
@@ -181,12 +181,12 @@ Future<RunResult> runAsync(List<String> cmd, {
   bool allowReentrantFlutter: false
 }) async {
   _traceCommand(cmd, workingDirectory: workingDirectory);
-  ProcessResult results = await processManager.run(
+  final ProcessResult results = await processManager.run(
     cmd,
     workingDirectory: workingDirectory,
     environment: _environment(allowReentrantFlutter),
   );
-  RunResult runResults = new RunResult(results);
+  final RunResult runResults = new RunResult(results);
   printTrace(runResults.toString());
   return runResults;
 }
@@ -241,7 +241,7 @@ String runSync(List<String> cmd, {
 }
 
 void _traceCommand(List<String> args, { String workingDirectory }) {
-  String argsText = args.join(' ');
+  final String argsText = args.join(' ');
   if (workingDirectory == null)
     printTrace(argsText);
   else
@@ -257,7 +257,7 @@ String _runWithLoggingSync(List<String> cmd, {
   bool hideStdout: false,
 }) {
   _traceCommand(cmd, workingDirectory: workingDirectory);
-  ProcessResult results = processManager.runSync(
+  final ProcessResult results = processManager.runSync(
     cmd,
     workingDirectory: workingDirectory,
     environment: _environment(allowReentrantFlutter),
@@ -312,7 +312,7 @@ class RunResult {
 
   @override
   String toString() {
-    StringBuffer out = new StringBuffer();
+    final StringBuffer out = new StringBuffer();
     if (processResult.stdout.isNotEmpty)
       out.writeln(processResult.stdout);
     if (processResult.stderr.isNotEmpty)

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

@@ -28,10 +28,10 @@ ProcessManager get processManager => context[ProcessManager];
 /// directory as long as there is no collision with the `"process"`
 /// subdirectory.
 void enableRecordingProcessManager(String location) {
-  ProcessManager originalProcessManager = processManager;
-  Directory dir = getRecordingSink(location, _kRecordingType);
-  ProcessManager delegate = const LocalProcessManager();
-  RecordingProcessManager manager = new RecordingProcessManager(delegate, dir);
+  final ProcessManager originalProcessManager = processManager;
+  final Directory dir = getRecordingSink(location, _kRecordingType);
+  final ProcessManager delegate = const LocalProcessManager();
+  final RecordingProcessManager manager = new RecordingProcessManager(delegate, dir);
   addShutdownHook(() async {
     await manager.flush(finishRunningProcesses: true);
     context.setVariable(ProcessManager, originalProcessManager);
@@ -48,7 +48,7 @@ void enableRecordingProcessManager(String location) {
 /// recorded (i.e. the result of having been previously passed to
 /// [enableRecordingProcessManager]), or a [ToolExit] will be thrown.
 Future<Null> enableReplayProcessManager(String location) async {
-  Directory dir = getReplaySource(location, _kRecordingType);
+  final Directory dir = getReplaySource(location, _kRecordingType);
 
   ProcessManager manager;
   try {

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

@@ -22,7 +22,7 @@ bool get isRunningOnBot {
 }
 
 String hex(List<int> bytes) {
-  StringBuffer result = new StringBuffer();
+  final StringBuffer result = new StringBuffer();
   for (int part in bytes)
     result.write('${part < 16 ? '0' : ''}${part.toRadixString(16)}');
   return result.toString();
@@ -55,18 +55,18 @@ String pluralize(String word, int count) => count == 1 ? word : word + 's';
 
 /// Return the name of an enum item.
 String getEnumName(dynamic enumItem) {
-  String name = '$enumItem';
-  int index = name.indexOf('.');
+  final String name = '$enumItem';
+  final int index = name.indexOf('.');
   return index == -1 ? name : name.substring(index + 1);
 }
 
 File getUniqueFile(Directory dir, String baseName, String ext) {
-  FileSystem fs = dir.fileSystem;
+  final FileSystem fs = dir.fileSystem;
   int i = 1;
 
   while (true) {
-    String name = '${baseName}_${i.toString().padLeft(2, '0')}.$ext';
-    File file = fs.file(fs.path.join(dir.path, name));
+    final String name = '${baseName}_${i.toString().padLeft(2, '0')}.$ext';
+    final File file = fs.file(fs.path.join(dir.path, name));
     if (!file.existsSync())
       return file;
     i++;
@@ -87,7 +87,7 @@ String getElapsedAsMilliseconds(Duration duration) => '${duration.inMilliseconds
 /// Return a relative path if [fullPath] is contained by the cwd, else return an
 /// absolute path.
 String getDisplayPath(String fullPath) {
-  String cwd = fs.currentDirectory.path + fs.path.separator;
+  final String cwd = fs.currentDirectory.path + fs.path.separator;
   return fullPath.startsWith(cwd) ?  fullPath.substring(cwd.length) : fullPath;
 }
 
@@ -114,10 +114,10 @@ class ItemListNotifier<T> {
   List<T> get items => _items.toList();
 
   void updateWithNewList(List<T> updatedList) {
-    Set<T> updatedSet = new Set<T>.from(updatedList);
+    final Set<T> updatedSet = new Set<T>.from(updatedList);
 
-    Set<T> addedItems = updatedSet.difference(_items);
-    Set<T> removedItems = _items.difference(updatedSet);
+    final Set<T> addedItems = updatedSet.difference(_items);
+    final Set<T> removedItems = _items.difference(updatedSet);
 
     _items = updatedSet;
 
@@ -140,7 +140,7 @@ class SettingsFile {
       line = line.trim();
       if (line.startsWith('#') || line.isEmpty)
         continue;
-      int index = line.indexOf('=');
+      final int index = line.indexOf('=');
       if (index != -1)
         values[line.substring(0, index)] = line.substring(index + 1);
     }
@@ -174,7 +174,7 @@ class Uuid {
   /// random numbers as the source of the generated uuid.
   String generateV4() {
     // Generate xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx / 8-4-4-4-12.
-    int special = 8 + _random.nextInt(4);
+    final int special = 8 + _random.nextInt(4);
 
     return
       '${_bitsDigits(16, 4)}${_bitsDigits(16, 4)}-'

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

@@ -43,15 +43,15 @@ class Version implements Comparable<Version> {
 
   /// Creates a new [Version] by parsing [text].
   factory Version.parse(String text) {
-    Match match = versionPattern.firstMatch(text);
+    final Match match = versionPattern.firstMatch(text);
     if (match == null) {
       return null;
     }
 
     try {
-      int major = int.parse(match[1] ?? '0');
-      int minor = int.parse(match[3] ?? '0');
-      int patch = int.parse(match[5] ?? '0');
+      final int major = int.parse(match[1] ?? '0');
+      final int minor = int.parse(match[3] ?? '0');
+      final int patch = int.parse(match[5] ?? '0');
       return new Version._(major, minor, patch, text);
     } on FormatException {
       return null;

packages/flutter_tools/lib/src/build_info.dart

@@ -130,7 +130,7 @@ String getBuildDirectory() {
   if (context == null || config == null)
     return 'build';
 
-  String buildDir = config.getValue('build-dir') ?? 'build';
+  final String buildDir = config.getValue('build-dir') ?? 'build';
   if (fs.path.isAbsolute(buildDir)) {
     throw new Exception(
         'build-dir config setting in ${config.configPath} must be relative');

packages/flutter_tools/lib/src/cache.dart

@@ -89,7 +89,7 @@ class Cache {
 
   static String get engineRevision {
     if (_engineRevision == null) {
-      File revisionFile = fs.file(fs.path.join(flutterRoot, 'bin', 'internal', 'engine.version'));
+      final File revisionFile = fs.file(fs.path.join(flutterRoot, 'bin', 'internal', 'engine.version'));
       if (revisionFile.existsSync())
         _engineRevision = revisionFile.readAsStringSync().trim();
     }
@@ -108,7 +108,7 @@ class Cache {
 
   /// Return a directory in the cache dir. For `pkg`, this will return `bin/cache/pkg`.
   Directory getCacheDir(String name) {
-    Directory dir = fs.directory(fs.path.join(getRoot().path, name));
+    final Directory dir = fs.directory(fs.path.join(getRoot().path, name));
     if (!dir.existsSync())
       dir.createSync(recursive: true);
     return dir;
@@ -124,12 +124,12 @@ class Cache {
   }
 
   String getVersionFor(String artifactName) {
-    File versionFile = fs.file(fs.path.join(_rootOverride?.path ?? flutterRoot, 'bin', 'internal', '$artifactName.version'));
+    final File versionFile = fs.file(fs.path.join(_rootOverride?.path ?? flutterRoot, 'bin', 'internal', '$artifactName.version'));
     return versionFile.existsSync() ? versionFile.readAsStringSync().trim() : null;
   }
 
   String getStampFor(String artifactName) {
-    File stampFile = getStampFileFor(artifactName);
+    final File stampFile = getStampFileFor(artifactName);
     return stampFile.existsSync() ? stampFile.readAsStringSync().trim() : null;
   }
 
@@ -142,8 +142,8 @@ class Cache {
   }
 
   bool isUpToDate() {
-    MaterialFonts materialFonts = new MaterialFonts(cache);
-    FlutterEngine engine = new FlutterEngine(cache);
+    final MaterialFonts materialFonts = new MaterialFonts(cache);
+    final FlutterEngine engine = new FlutterEngine(cache);
 
     return materialFonts.isUpToDate() && engine.isUpToDate();
   }
@@ -151,14 +151,14 @@ class Cache {
   Future<String> getThirdPartyFile(String urlStr, String serviceName, {
     bool unzip: false
   }) async {
-    Uri url = Uri.parse(urlStr);
-    Directory thirdPartyDir = getArtifactDirectory('third_party');
+    final Uri url = Uri.parse(urlStr);
+    final Directory thirdPartyDir = getArtifactDirectory('third_party');
 
-    Directory serviceDir = fs.directory(fs.path.join(thirdPartyDir.path, serviceName));
+    final Directory serviceDir = fs.directory(fs.path.join(thirdPartyDir.path, serviceName));
     if (!serviceDir.existsSync())
       serviceDir.createSync(recursive: true);
 
-    File cachedFile = fs.file(fs.path.join(serviceDir.path, url.pathSegments.last));
+    final File cachedFile = fs.file(fs.path.join(serviceDir.path, url.pathSegments.last));
     if (!cachedFile.existsSync()) {
       try {
         await _downloadFileToCache(url, cachedFile, unzip);
@@ -174,11 +174,11 @@ class Cache {
   Future<Null> updateAll() async {
     if (!_lockEnabled)
       return null;
-    MaterialFonts materialFonts = new MaterialFonts(cache);
+    final MaterialFonts materialFonts = new MaterialFonts(cache);
     if (!materialFonts.isUpToDate())
       await materialFonts.download();
 
-    FlutterEngine engine = new FlutterEngine(cache);
+    final FlutterEngine engine = new FlutterEngine(cache);
     if (!engine.isUpToDate())
       await engine.download();
   }
@@ -190,17 +190,17 @@ class Cache {
     if (!location.parent.existsSync())
       location.parent.createSync(recursive: true);
 
-    List<int> fileBytes = await fetchUrl(url);
+    final List<int> fileBytes = await fetchUrl(url);
     if (unzip) {
       if (location is Directory && !location.existsSync())
         location.createSync(recursive: true);
 
-      File tempFile = fs.file(fs.path.join(fs.systemTempDirectory.path, '${url.toString().hashCode}.zip'));
+      final File tempFile = fs.file(fs.path.join(fs.systemTempDirectory.path, '${url.toString().hashCode}.zip'));
       tempFile.writeAsBytesSync(fileBytes, flush: true);
       os.unzip(tempFile, location);
       tempFile.deleteSync();
     } else {
-      File file = location;
+      final File file = location;
       file.writeAsBytesSync(fileBytes, flush: true);
     }
   }
@@ -220,9 +220,9 @@ class MaterialFonts {
   }
 
   Future<Null> download() {
-    Status status = logger.startProgress('Downloading Material fonts...', expectSlowOperation: true);
+    final Status status = logger.startProgress('Downloading Material fonts...', expectSlowOperation: true);
 
-    Directory fontsDir = cache.getArtifactDirectory(kName);
+    final Directory fontsDir = cache.getArtifactDirectory(kName);
     if (fontsDir.existsSync())
       fontsDir.deleteSync(recursive: true);
 
@@ -250,7 +250,7 @@ class FlutterEngine {
 
   // Return a list of (cache directory path, download URL path) tuples.
   List<List<String>> _getBinaryDirs() {
-    List<List<String>> binaryDirs = <List<String>>[];
+    final List<List<String>> binaryDirs = <List<String>>[];
 
     if (cache.includeAllPlatforms)
       binaryDirs
@@ -309,16 +309,16 @@ class FlutterEngine {
   ];
 
   bool isUpToDate() {
-    Directory pkgDir = cache.getCacheDir('pkg');
+    final Directory pkgDir = cache.getCacheDir('pkg');
     for (String pkgName in _getPackageDirs()) {
-      String pkgPath = fs.path.join(pkgDir.path, pkgName);
+      final String pkgPath = fs.path.join(pkgDir.path, pkgName);
       if (!fs.directory(pkgPath).existsSync())
         return false;
     }
 
-    Directory engineDir = cache.getArtifactDirectory(kName);
+    final Directory engineDir = cache.getArtifactDirectory(kName);
     for (List<String> toolsDir in _getBinaryDirs()) {
-      Directory dir = fs.directory(fs.path.join(engineDir.path, toolsDir[0]));
+      final Directory dir = fs.directory(fs.path.join(engineDir.path, toolsDir[0]));
       if (!dir.existsSync())
         return false;
     }
@@ -327,33 +327,33 @@ class FlutterEngine {
   }
 
   Future<Null> download() async {
-    String engineVersion = cache.getVersionFor(kName);
-    String url = 'https://storage.googleapis.com/flutter_infra/flutter/$engineVersion/';
+    final String engineVersion = cache.getVersionFor(kName);
+    final String url = 'https://storage.googleapis.com/flutter_infra/flutter/$engineVersion/';
 
-    Directory pkgDir = cache.getCacheDir('pkg');
+    final Directory pkgDir = cache.getCacheDir('pkg');
     for (String pkgName in _getPackageDirs()) {
-      String pkgPath = fs.path.join(pkgDir.path, pkgName);
-      Directory dir = fs.directory(pkgPath);
+      final String pkgPath = fs.path.join(pkgDir.path, pkgName);
+      final Directory dir = fs.directory(pkgPath);
       if (dir.existsSync())
         dir.deleteSync(recursive: true);
       await _downloadItem('Downloading package $pkgName...', url + pkgName + '.zip', pkgDir);
     }
 
-    Directory engineDir = cache.getArtifactDirectory(kName);
+    final Directory engineDir = cache.getArtifactDirectory(kName);
     if (engineDir.existsSync())
       engineDir.deleteSync(recursive: true);
 
     for (List<String> toolsDir in _getBinaryDirs()) {
-      String cacheDir = toolsDir[0];
-      String urlPath = toolsDir[1];
-      Directory dir = fs.directory(fs.path.join(engineDir.path, cacheDir));
+      final String cacheDir = toolsDir[0];
+      final String urlPath = toolsDir[1];
+      final Directory dir = fs.directory(fs.path.join(engineDir.path, cacheDir));
       await _downloadItem('Downloading $cacheDir tools...', url + urlPath, dir);
 
       _makeFilesExecutable(dir);
 
-      File frameworkZip = fs.file(fs.path.join(dir.path, 'Flutter.framework.zip'));
+      final File frameworkZip = fs.file(fs.path.join(dir.path, 'Flutter.framework.zip'));
       if (frameworkZip.existsSync()) {
-        Directory framework = fs.directory(fs.path.join(dir.path, 'Flutter.framework'));
+        final Directory framework = fs.directory(fs.path.join(dir.path, 'Flutter.framework'));
         framework.createSync();
         os.unzip(frameworkZip, framework);
       }
@@ -365,7 +365,7 @@ class FlutterEngine {
   void _makeFilesExecutable(Directory dir) {
     for (FileSystemEntity entity in dir.listSync()) {
       if (entity is File) {
-        String name = fs.path.basename(entity.path);
+        final String name = fs.path.basename(entity.path);
         if (name == 'sky_snapshot' || name == 'sky_shell')
           os.makeExecutable(entity);
       }
@@ -373,7 +373,7 @@ class FlutterEngine {
   }
 
   Future<Null> _downloadItem(String message, String url, Directory dest) {
-    Status status = logger.startProgress(message, expectSlowOperation: true);
+    final Status status = logger.startProgress(message, expectSlowOperation: true);
     return Cache._downloadFileToCache(Uri.parse(url), dest, true).then<Null>((Null value) {
       status.stop();
     }).whenComplete(() {

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

@@ -39,7 +39,7 @@ abstract class AnalyzeBase {
 
   void writeBenchmark(Stopwatch stopwatch, int errorCount, int membersMissingDocumentation) {
     final String benchmarkOut = 'analysis_benchmark.json';
-    Map<String, dynamic> data = <String, dynamic>{
+    final Map<String, dynamic> data = <String, dynamic>{
       'time': (stopwatch.elapsedMilliseconds / 1000.0),
       'issues': errorCount,
       'missingDartDocs': membersMissingDocumentation
@@ -56,8 +56,8 @@ abstract class AnalyzeBase {
 bool inRepo(List<String> fileList) {
   if (fileList == null || fileList.isEmpty)
     fileList = <String>[fs.path.current];
-  String root = fs.path.normalize(fs.path.absolute(Cache.flutterRoot));
-  String prefix = root + fs.path.separator;
+  final String root = fs.path.normalize(fs.path.absolute(Cache.flutterRoot));
+  final String prefix = root + fs.path.separator;
   for (String file in fileList) {
     file = fs.path.normalize(fs.path.absolute(file));
     if (file == root || file.startsWith(prefix))

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

@@ -46,7 +46,7 @@ class AnalyzeContinuously extends AnalyzeBase {
       analysisTarget = fs.currentDirectory.path;
     }
 
-    AnalysisServer server = new AnalysisServer(dartSdkPath, directories);
+    final AnalysisServer server = new AnalysisServer(dartSdkPath, directories);
     server.onAnalyzing.listen((bool isAnalyzing) => _handleAnalysisStatus(server, isAnalyzing));
     server.onErrors.listen(_handleAnalysisErrors);
 
@@ -55,7 +55,7 @@ class AnalyzeContinuously extends AnalyzeBase {
     await server.start();
     final int exitCode = await server.onExit;
 
-    String message = 'Analysis server exited with code $exitCode.';
+    final String message = 'Analysis server exited with code $exitCode.';
     if (exitCode != 0)
       throwToolExit(message, exitCode: exitCode);
     printStatus(message);
@@ -98,8 +98,8 @@ class AnalyzeContinuously extends AnalyzeBase {
       // Print an analysis summary.
       String errorsMessage;
 
-      int issueCount = errors.length;
-      int issueDiff = issueCount - lastErrorCount;
+      final int issueCount = errors.length;
+      final int issueDiff = issueCount - lastErrorCount;
       lastErrorCount = issueCount;
 
       if (firstAnalysis)
@@ -113,8 +113,8 @@ class AnalyzeContinuously extends AnalyzeBase {
       else
         errorsMessage = 'no issues found';
 
-      String files = '${analyzedPaths.length} ${pluralize('file', analyzedPaths.length)}';
-      String seconds = (analysisTimer.elapsedMilliseconds / 1000.0).toStringAsFixed(2);
+      final String files = '${analyzedPaths.length} ${pluralize('file', analyzedPaths.length)}';
+      final String seconds = (analysisTimer.elapsedMilliseconds / 1000.0).toStringAsFixed(2);
       printStatus('$errorsMessage • analyzed $files, $seconds seconds');
 
       if (firstAnalysis && isBenchmarking) {
@@ -156,8 +156,8 @@ class AnalysisServer {
   int _id = 0;
 
   Future<Null> start() async {
-    String snapshot = fs.path.join(sdk, 'bin/snapshots/analysis_server.dart.snapshot');
-    List<String> command = <String>[
+    final String snapshot = fs.path.join(sdk, 'bin/snapshots/analysis_server.dart.snapshot');
+    final List<String> command = <String>[
       fs.path.join(dartSdkPath, 'bin', 'dart'),
       snapshot,
       '--sdk',
@@ -168,10 +168,10 @@ class AnalysisServer {
     _process = await processManager.start(command);
     _process.exitCode.whenComplete(() => _process = null);
 
-    Stream<String> errorStream = _process.stderr.transform(UTF8.decoder).transform(const LineSplitter());
+    final Stream<String> errorStream = _process.stderr.transform(UTF8.decoder).transform(const LineSplitter());
     errorStream.listen((String error) => printError(error));
 
-    Stream<String> inStream = _process.stdout.transform(UTF8.decoder).transform(const LineSplitter());
+    final Stream<String> inStream = _process.stdout.transform(UTF8.decoder).transform(const LineSplitter());
     inStream.listen(_handleServerResponse);
 
     // Available options (many of these are obsolete):
@@ -199,7 +199,7 @@ class AnalysisServer {
   Future<int> get onExit => _process.exitCode;
 
   void _sendCommand(String method, Map<String, dynamic> params) {
-    String message = JSON.encode(<String, dynamic> {
+    final String message = JSON.encode(<String, dynamic> {
       'id': (++_id).toString(),
       'method': method,
       'params': params
@@ -211,12 +211,12 @@ class AnalysisServer {
   void _handleServerResponse(String line) {
     printTrace('<== $line');
 
-    dynamic response = JSON.decode(line);
+    final dynamic response = JSON.decode(line);
 
     if (response is Map<dynamic, dynamic>) {
       if (response['event'] != null) {
-        String event = response['event'];
-        dynamic params = response['params'];
+        final String event = response['event'];
+        final dynamic params = response['params'];
 
         if (params is Map<dynamic, dynamic>) {
           if (event == 'server.status')
@@ -228,7 +228,7 @@ class AnalysisServer {
         }
       } else if (response['error'] != null) {
         // Fields are 'code', 'message', and 'stackTrace'.
-        Map<String, dynamic> error = response['error'];
+        final Map<String, dynamic> error = response['error'];
         printError('Error response from the server: ${error['code']} ${error['message']}');
         if (error['stackTrace'] != null)
           printError(error['stackTrace']);
@@ -239,7 +239,7 @@ class AnalysisServer {
   void _handleStatus(Map<String, dynamic> statusInfo) {
     // {"event":"server.status","params":{"analysis":{"isAnalyzing":true}}}
     if (statusInfo['analysis'] != null) {
-      bool isAnalyzing = statusInfo['analysis']['isAnalyzing'];
+      final bool isAnalyzing = statusInfo['analysis']['isAnalyzing'];
       _analyzingController.add(isAnalyzing);
     }
   }
@@ -253,8 +253,8 @@ class AnalysisServer {
 
   void _handleAnalysisIssues(Map<String, dynamic> issueInfo) {
     // {"event":"analysis.errors","params":{"file":"/Users/.../lib/main.dart","errors":[]}}
-    String file = issueInfo['file'];
-    List<AnalysisError> errors = issueInfo['errors'].map((Map<String, dynamic> json) => new AnalysisError(json)).toList();
+    final String file = issueInfo['file'];
+    final List<AnalysisError> errors = issueInfo['errors'].map((Map<String, dynamic> json) => new AnalysisError(json)).toList();
     _errorsController.add(new FileAnalysisErrors(file, errors));
   }
 
@@ -299,7 +299,7 @@ class AnalysisError implements Comparable<AnalysisError> {
     if (offset != other.offset)
       return offset - other.offset;
 
-    int diff = other.severityLevel - severityLevel;
+    final int diff = other.severityLevel - severityLevel;
     if (diff != 0)
       return diff;
 
@@ -308,7 +308,7 @@ class AnalysisError implements Comparable<AnalysisError> {
 
   @override
   String toString() {
-    String relativePath = fs.path.relative(file);
+    final String relativePath = fs.path.relative(file);
     return '${severity.toLowerCase().padLeft(7)} • $message • $relativePath:$startLine:$startColumn';
   }
 

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

@@ -28,13 +28,13 @@ class AnalyzeOnce extends AnalyzeBase {
 
   @override
   Future<Null> analyze() async {
-    Stopwatch stopwatch = new Stopwatch()..start();
-    Set<Directory> pubSpecDirectories = new HashSet<Directory>();
-    List<File> dartFiles = <File>[];
+    final Stopwatch stopwatch = new Stopwatch()..start();
+    final Set<Directory> pubSpecDirectories = new HashSet<Directory>();
+    final List<File> dartFiles = <File>[];
 
     for (String file in argResults.rest.toList()) {
       file = fs.path.normalize(fs.path.absolute(file));
-      String root = fs.path.rootPrefix(file);
+      final String root = fs.path.rootPrefix(file);
       dartFiles.add(fs.file(file));
       while (file != root) {
         file = fs.path.dirname(file);
@@ -45,15 +45,15 @@ class AnalyzeOnce extends AnalyzeBase {
       }
     }
 
-    bool currentDirectory = argResults['current-directory'] && (argResults.wasParsed('current-directory') || dartFiles.isEmpty);
-    bool currentPackage = argResults['current-package'] && (argResults.wasParsed('current-package') || dartFiles.isEmpty);
-    bool flutterRepo = argResults['flutter-repo'] || inRepo(argResults.rest);
+    final bool currentDirectory = argResults['current-directory'] && (argResults.wasParsed('current-directory') || dartFiles.isEmpty);
+    final bool currentPackage = argResults['current-package'] && (argResults.wasParsed('current-package') || dartFiles.isEmpty);
+    final bool flutterRepo = argResults['flutter-repo'] || inRepo(argResults.rest);
 
     //TODO (pq): revisit package and directory defaults
 
     if (currentDirectory  && !flutterRepo) {
       // ./*.dart
-      Directory currentDirectory = fs.directory('.');
+      final Directory currentDirectory = fs.directory('.');
       bool foundOne = false;
       for (FileSystemEntity entry in currentDirectory.listSync()) {
         if (isDartFile(entry)) {
@@ -67,7 +67,7 @@ class AnalyzeOnce extends AnalyzeBase {
 
     if (currentPackage && !flutterRepo) {
       // **/.*dart
-      Directory currentDirectory = fs.directory('.');
+      final Directory currentDirectory = fs.directory('.');
       _collectDartFiles(currentDirectory, dartFiles);
       pubSpecDirectories.add(currentDirectory);
     }
@@ -80,21 +80,21 @@ class AnalyzeOnce extends AnalyzeBase {
     }
 
     // determine what all the various .packages files depend on
-    PackageDependencyTracker dependencies = new PackageDependencyTracker();
+    final PackageDependencyTracker dependencies = new PackageDependencyTracker();
     for (Directory directory in pubSpecDirectories) {
-      String pubSpecYamlPath = fs.path.join(directory.path, 'pubspec.yaml');
-      File pubSpecYamlFile = fs.file(pubSpecYamlPath);
+      final String pubSpecYamlPath = fs.path.join(directory.path, 'pubspec.yaml');
+      final File pubSpecYamlFile = fs.file(pubSpecYamlPath);
       if (pubSpecYamlFile.existsSync()) {
         // we are analyzing the actual canonical source for this package;
         // make sure we remember that, in case all the packages are actually
         // pointing elsewhere somehow.
-        yaml.YamlMap pubSpecYaml = yaml.loadYaml(fs.file(pubSpecYamlPath).readAsStringSync());
-        String packageName = pubSpecYaml['name'];
-        String packagePath = fs.path.normalize(fs.path.absolute(fs.path.join(directory.path, 'lib')));
+        final yaml.YamlMap pubSpecYaml = yaml.loadYaml(fs.file(pubSpecYamlPath).readAsStringSync());
+        final String packageName = pubSpecYaml['name'];
+        final String packagePath = fs.path.normalize(fs.path.absolute(fs.path.join(directory.path, 'lib')));
         dependencies.addCanonicalCase(packageName, packagePath, pubSpecYamlPath);
       }
-      String dotPackagesPath = fs.path.join(directory.path, '.packages');
-      File dotPackages = fs.file(dotPackagesPath);
+      final String dotPackagesPath = fs.path.join(directory.path, '.packages');
+      final File dotPackages = fs.file(dotPackagesPath);
       if (dotPackages.existsSync()) {
         // this directory has opinions about what we should be using
         dotPackages
@@ -102,10 +102,10 @@ class AnalyzeOnce extends AnalyzeBase {
           .split('\n')
           .where((String line) => !line.startsWith(new RegExp(r'^ *#')))
           .forEach((String line) {
-            int colon = line.indexOf(':');
+            final int colon = line.indexOf(':');
             if (colon > 0) {
-              String packageName = line.substring(0, colon);
-              String packagePath = fs.path.fromUri(line.substring(colon+1));
+              final String packageName = line.substring(0, colon);
+              final String packagePath = fs.path.fromUri(line.substring(colon+1));
               // Ensure that we only add the `analyzer` package defined in the vended SDK (and referred to with a local fs.path. directive).
               // Analyzer package versions reached via transitive dependencies (e.g., via `test`) are ignored since they would produce
               // spurious conflicts.
@@ -118,7 +118,7 @@ class AnalyzeOnce extends AnalyzeBase {
 
     // prepare a union of all the .packages files
     if (dependencies.hasConflicts) {
-      StringBuffer message = new StringBuffer();
+      final StringBuffer message = new StringBuffer();
       message.writeln(dependencies.generateConflictReport());
       message.writeln('Make sure you have run "pub upgrade" in all the directories mentioned above.');
       if (dependencies.hasConflictsAffectingFlutterRepo) {
@@ -131,7 +131,7 @@ class AnalyzeOnce extends AnalyzeBase {
           '"pub deps --style=list" and "pub upgrade --verbosity=solver" in the affected directories.');
       throwToolExit(message.toString());
     }
-    Map<String, String> packages = dependencies.asPackageMap();
+    final Map<String, String> packages = dependencies.asPackageMap();
 
     Cache.releaseLockEarly();
 
@@ -142,16 +142,16 @@ class AnalyzeOnce extends AnalyzeBase {
         logger.printStatus('Analyzing ${dartFiles.length} files...');
       }
     }
-    DriverOptions options = new DriverOptions();
+    final DriverOptions options = new DriverOptions();
     options.dartSdkPath = argResults['dart-sdk'];
     options.packageMap = packages;
     options.analysisOptionsFile = flutterRepo
         ? fs.path.join(Cache.flutterRoot, '.analysis_options_repo')
         : fs.path.join(Cache.flutterRoot, 'packages', 'flutter', 'lib', 'analysis_options_user.yaml');
-    AnalysisDriver analyzer = new AnalysisDriver(options);
+    final AnalysisDriver analyzer = new AnalysisDriver(options);
 
     // TODO(pq): consider error handling
-    List<AnalysisErrorDescription> errors = analyzer.analyze(dartFiles);
+    final List<AnalysisErrorDescription> errors = analyzer.analyze(dartFiles);
 
     int errorCount = 0;
     int membersMissingDocumentation = 0;
@@ -176,7 +176,7 @@ class AnalyzeOnce extends AnalyzeBase {
     dumpErrors(errors.map<String>((AnalysisErrorDescription error) => error.asString()));
 
     stopwatch.stop();
-    String elapsed = (stopwatch.elapsedMilliseconds / 1000.0).toStringAsFixed(1);
+    final String elapsed = (stopwatch.elapsedMilliseconds / 1000.0).toStringAsFixed(1);
 
     if (isBenchmarking)
       writeBenchmark(stopwatch, errorCount, membersMissingDocumentation);
@@ -200,7 +200,7 @@ class AnalyzeOnce extends AnalyzeBase {
   List<String> flutterRootComponents;
   bool isFlutterLibrary(String filename) {
     flutterRootComponents ??= fs.path.normalize(fs.path.absolute(Cache.flutterRoot)).split(fs.path.separator);
-    List<String> filenameComponents = fs.path.normalize(fs.path.absolute(filename)).split(fs.path.separator);
+    final List<String> filenameComponents = fs.path.normalize(fs.path.absolute(filename)).split(fs.path.separator);
     if (filenameComponents.length < flutterRootComponents.length + 4) // the 4: 'packages', package_name, 'lib', file_name
       return false;
     for (int index = 0; index < flutterRootComponents.length; index += 1) {
@@ -225,7 +225,7 @@ class AnalyzeOnce extends AnalyzeBase {
       if (isDartFile(entity))
         collected.add(entity);
       if (entity is Directory) {
-        String name = fs.path.basename(entity.path);
+        final String name = fs.path.basename(entity.path);
         if (!name.startsWith('.') && name != 'packages')
           _collectDartFiles(entity, collected);
       }
@@ -262,10 +262,10 @@ class PackageDependency {
   }
   void describeConflict(StringBuffer result) {
     assert(hasConflict);
-    List<String> targets = values.keys.toList();
+    final List<String> targets = values.keys.toList();
     targets.sort((String a, String b) => values[b].length.compareTo(values[a].length));
     for (String target in targets) {
-      int count = values[target].length;
+      final int count = values[target].length;
       result.writeln('  $count ${count == 1 ? 'source wants' : 'sources want'} "$target":');
       bool canonical = false;
       for (String source in values[target]) {
@@ -308,7 +308,7 @@ class PackageDependencyTracker {
 
   String generateConflictReport() {
     assert(hasConflicts);
-    StringBuffer result = new StringBuffer();
+    final StringBuffer result = new StringBuffer();
     for (String package in packages.keys.where((String package) => packages[package].hasConflict)) {
       result.writeln('Package "$package" has conflicts:');
       packages[package].describeConflict(result);
@@ -317,7 +317,7 @@ class PackageDependencyTracker {
   }
 
   Map<String, String> asPackageMap() {
-    Map<String, String> result = <String, String>{};
+    final Map<String, String> result = <String, String>{};
     for (String package in packages.keys)
       result[package] = packages[package].target;
     return result;

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

@@ -54,14 +54,14 @@ abstract class BuildSubCommand extends FlutterCommand {
   @mustCallSuper
   Future<Null> runCommand() async {
     if (isRunningOnBot) {
-      File dotPackages = fs.file('.packages');
+      final File dotPackages = fs.file('.packages');
       printStatus('Contents of .packages:');
       if (dotPackages.existsSync())
         printStatus(dotPackages.readAsStringSync());
       else
         printError('File not found: ${dotPackages.absolute.path}');
 
-      File pubspecLock = fs.file('pubspec.lock');
+      final File pubspecLock = fs.file('pubspec.lock');
       printStatus('Contents of pubspec.lock:');
       if (pubspecLock.existsSync())
         printStatus(pubspecLock.readAsStringSync());
@@ -86,7 +86,7 @@ class BuildCleanCommand extends FlutterCommand {
 
   @override
   Future<Null> runCommand() async {
-    Directory buildDir = fs.directory(getBuildDirectory());
+    final Directory buildDir = fs.directory(getBuildDirectory());
     printStatus("Deleting '${buildDir.path}${fs.path.separator}'.");
 
     if (!buildDir.existsSync())

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

@@ -45,15 +45,15 @@ class BuildAotCommand extends BuildSubCommand {
   @override
   Future<Null> runCommand() async {
     await super.runCommand();
-    String targetPlatform = argResults['target-platform'];
-    TargetPlatform platform = getTargetPlatformForName(targetPlatform);
+    final String targetPlatform = argResults['target-platform'];
+    final TargetPlatform platform = getTargetPlatformForName(targetPlatform);
     if (platform == null)
       throwToolExit('Unknown platform: $targetPlatform');
 
-    String typeName = artifacts.getEngineType(platform, getBuildMode());
-    Status status = logger.startProgress('Building AOT snapshot in ${getModeName(getBuildMode())} mode ($typeName)...',
+    final String typeName = artifacts.getEngineType(platform, getBuildMode());
+    final Status status = logger.startProgress('Building AOT snapshot in ${getModeName(getBuildMode())} mode ($typeName)...',
         expectSlowOperation: true);
-    String outputPath = await buildAotSnapshot(
+    final String outputPath = await buildAotSnapshot(
       findMainDartFile(targetFile),
       platform,
       getBuildMode(),
@@ -116,31 +116,31 @@ Future<String> _buildAotSnapshot(
     return null;
   }
 
-  String genSnapshot = artifacts.getArtifactPath(Artifact.genSnapshot, platform, buildMode);
+  final String genSnapshot = artifacts.getArtifactPath(Artifact.genSnapshot, platform, buildMode);
 
-  Directory outputDir = fs.directory(outputPath);
+  final Directory outputDir = fs.directory(outputPath);
   outputDir.createSync(recursive: true);
-  String vmSnapshotData = fs.path.join(outputDir.path, 'vm_snapshot_data');
-  String vmSnapshotInstructions = fs.path.join(outputDir.path, 'vm_snapshot_instr');
-  String isolateSnapshotData = fs.path.join(outputDir.path, 'isolate_snapshot_data');
-  String isolateSnapshotInstructions = fs.path.join(outputDir.path, 'isolate_snapshot_instr');
+  final String vmSnapshotData = fs.path.join(outputDir.path, 'vm_snapshot_data');
+  final String vmSnapshotInstructions = fs.path.join(outputDir.path, 'vm_snapshot_instr');
+  final String isolateSnapshotData = fs.path.join(outputDir.path, 'isolate_snapshot_data');
+  final String isolateSnapshotInstructions = fs.path.join(outputDir.path, 'isolate_snapshot_instr');
 
-  String vmEntryPoints = artifacts.getArtifactPath(Artifact.dartVmEntryPointsTxt, platform, buildMode);
-  String ioEntryPoints = artifacts.getArtifactPath(Artifact.dartIoEntriesTxt, platform, buildMode);
+  final String vmEntryPoints = artifacts.getArtifactPath(Artifact.dartVmEntryPointsTxt, platform, buildMode);
+  final String ioEntryPoints = artifacts.getArtifactPath(Artifact.dartIoEntriesTxt, platform, buildMode);
 
-  PackageMap packageMap = new PackageMap(PackageMap.globalPackagesPath);
-  String packageMapError = packageMap.checkValid();
+  final PackageMap packageMap = new PackageMap(PackageMap.globalPackagesPath);
+  final String packageMapError = packageMap.checkValid();
   if (packageMapError != null) {
     printError(packageMapError);
     return null;
   }
 
-  String skyEnginePkg = _getSdkExtensionPath(packageMap, 'sky_engine');
-  String uiPath = fs.path.join(skyEnginePkg, 'dart_ui', 'ui.dart');
-  String jniPath = fs.path.join(skyEnginePkg, 'dart_jni', 'jni.dart');
-  String vmServicePath = fs.path.join(skyEnginePkg, 'sdk_ext', 'vmservice_io.dart');
+  final String skyEnginePkg = _getSdkExtensionPath(packageMap, 'sky_engine');
+  final String uiPath = fs.path.join(skyEnginePkg, 'dart_ui', 'ui.dart');
+  final String jniPath = fs.path.join(skyEnginePkg, 'dart_jni', 'jni.dart');
+  final String vmServicePath = fs.path.join(skyEnginePkg, 'sdk_ext', 'vmservice_io.dart');
 
-  List<String> filePaths = <String>[
+  final List<String> filePaths = <String>[
     vmEntryPoints,
     ioEntryPoints,
     uiPath,
@@ -177,7 +177,7 @@ Future<String> _buildAotSnapshot(
       assert(false);
   }
 
-  List<String> missingFiles = filePaths.where((String p) => !fs.isFileSync(p)).toList();
+  final List<String> missingFiles = filePaths.where((String p) => !fs.isFileSync(p)).toList();
   if (missingFiles.isNotEmpty) {
     printError('Missing files: $missingFiles');
     return null;
@@ -187,7 +187,7 @@ Future<String> _buildAotSnapshot(
     return null;
   }
 
-  List<String> genSnapshotCmd = <String>[
+  final List<String> genSnapshotCmd = <String>[
     genSnapshot,
     '--assert_initializer',
     '--await_is_keyword',
@@ -242,7 +242,7 @@ Future<String> _buildAotSnapshot(
 
   genSnapshotCmd.add(mainPath);
 
-  RunResult results = await runAsync(genSnapshotCmd);
+  final RunResult results = await runAsync(genSnapshotCmd);
   if (results.exitCode != 0) {
     printError('Dart snapshot generator failed with exit code ${results.exitCode}');
     printError(results.toString());
@@ -255,16 +255,16 @@ Future<String> _buildAotSnapshot(
     printStatus('Building app.dylib...');
 
     // These names are known to from the engine.
-    String kVmSnapshotData = 'kDartVmSnapshotData';
-    String kIsolateSnapshotData = 'kDartIsolateSnapshotData';
+    final String kVmSnapshotData = 'kDartVmSnapshotData';
+    final String kIsolateSnapshotData = 'kDartIsolateSnapshotData';
 
-    String kVmSnapshotDataC = fs.path.join(outputDir.path, '$kVmSnapshotData.c');
-    String kIsolateSnapshotDataC = fs.path.join(outputDir.path, '$kIsolateSnapshotData.c');
-    String kVmSnapshotDataO = fs.path.join(outputDir.path, '$kVmSnapshotData.o');
-    String kIsolateSnapshotDataO = fs.path.join(outputDir.path, '$kIsolateSnapshotData.o');
-    String assemblyO = fs.path.join(outputDir.path, 'snapshot_assembly.o');
+    final String kVmSnapshotDataC = fs.path.join(outputDir.path, '$kVmSnapshotData.c');
+    final String kIsolateSnapshotDataC = fs.path.join(outputDir.path, '$kIsolateSnapshotData.c');
+    final String kVmSnapshotDataO = fs.path.join(outputDir.path, '$kVmSnapshotData.o');
+    final String kIsolateSnapshotDataO = fs.path.join(outputDir.path, '$kIsolateSnapshotData.o');
+    final String assemblyO = fs.path.join(outputDir.path, 'snapshot_assembly.o');
 
-    List<String> commonBuildOptions = <String>['-arch', 'arm64', '-miphoneos-version-min=8.0'];
+    final List<String> commonBuildOptions = <String>['-arch', 'arm64', '-miphoneos-version-min=8.0'];
 
     if (interpreter) {
       runCheckedSync(<String>['mv', vmSnapshotData, fs.path.join(outputDir.path, kVmSnapshotData)]);
@@ -289,9 +289,9 @@ Future<String> _buildAotSnapshot(
         ..addAll(<String>['-c', assembly, '-o', assemblyO]));
     }
 
-    String appSo = fs.path.join(outputDir.path, 'app.dylib');
+    final String appSo = fs.path.join(outputDir.path, 'app.dylib');
 
-    List<String> linkCommand = <String>['xcrun', 'clang']
+    final List<String> linkCommand = <String>['xcrun', 'clang']
       ..addAll(commonBuildOptions)
       ..addAll(<String>[
         '-dynamiclib',

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

@@ -39,7 +39,7 @@ class BuildFlxCommand extends BuildSubCommand {
   @override
   Future<Null> runCommand() async {
     await super.runCommand();
-    String outputPath = argResults['output-file'];
+    final String outputPath = argResults['output-file'];
 
     await build(
       mainPath: targetFile,

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

@@ -39,19 +39,19 @@ class BuildIOSCommand extends BuildSubCommand {
 
   @override
   Future<Null> runCommand() async {
-    bool forSimulator = argResults['simulator'];
+    final bool forSimulator = argResults['simulator'];
     defaultBuildMode = forSimulator ? BuildMode.debug : BuildMode.release;
 
     await super.runCommand();
     if (getCurrentHostPlatform() != HostPlatform.darwin_x64)
       throwToolExit('Building for iOS is only supported on the Mac.');
 
-    IOSApp app = applicationPackages.getPackageForPlatform(TargetPlatform.ios);
+    final IOSApp app = applicationPackages.getPackageForPlatform(TargetPlatform.ios);
 
     if (app == null)
       throwToolExit('Application not configured for iOS');
 
-    bool shouldCodesign = argResults['codesign'];
+    final bool shouldCodesign = argResults['codesign'];
 
     if (!forSimulator && !shouldCodesign) {
       printStatus('Warning: Building for device with codesigning disabled. You will '
@@ -61,12 +61,12 @@ class BuildIOSCommand extends BuildSubCommand {
     if (forSimulator && !isEmulatorBuildMode(getBuildMode()))
       throwToolExit('${toTitleCase(getModeName(getBuildMode()))} mode is not supported for emulators.');
 
-    String logTarget = forSimulator ? 'simulator' : 'device';
+    final String logTarget = forSimulator ? 'simulator' : 'device';
 
-    String typeName = artifacts.getEngineType(TargetPlatform.ios, getBuildMode());
-    Status status = logger.startProgress('Building $app for $logTarget ($typeName)...',
+    final String typeName = artifacts.getEngineType(TargetPlatform.ios, getBuildMode());
+    final Status status = logger.startProgress('Building $app for $logTarget ($typeName)...',
         expectSlowOperation: true);
-    XcodeBuildResult result = await buildXcodeProject(
+    final XcodeBuildResult result = await buildXcodeProject(
       app: app,
       mode: getBuildMode(),
       target: targetFile,

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

@@ -33,18 +33,18 @@ class ChannelCommand extends FlutterCommand {
   }
 
   Future<Null> _listChannels() async {
-    String currentBranch = runSync(
+    final String currentBranch = runSync(
         <String>['git', 'rev-parse', '--abbrev-ref', 'HEAD'],
         workingDirectory: Cache.flutterRoot);
 
     printStatus('Flutter channels:');
-    int result = await runCommandAndStreamOutput(
+    final int result = await runCommandAndStreamOutput(
       <String>['git', 'branch', '-r'],
       workingDirectory: Cache.flutterRoot,
       mapFunction: (String line) {
-        List<String> split = line.split('/');
+        final List<String> split = line.split('/');
         if (split.length < 2) return null;
-        String branchName = split[1];
+        final String branchName = split[1];
         if (branchName.startsWith('HEAD')) return null;
         if (branchName == currentBranch) return '* $branchName';
         return '  $branchName';
@@ -56,7 +56,7 @@ class ChannelCommand extends FlutterCommand {
 
   Future<Null> _switchChannel(String branchName) async {
     printStatus('Switching to flutter channel named $branchName');
-    int result = await runCommandAndStreamOutput(
+    final int result = await runCommandAndStreamOutput(
       <String>['git', 'checkout', branchName],
       workingDirectory: Cache.flutterRoot,
     );

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

@@ -49,7 +49,7 @@ class ConfigCommand extends FlutterCommand {
   @override
   Future<Null> runCommand() async {
     if (argResults.wasParsed('analytics')) {
-      bool value = argResults['analytics'];
+      final bool value = argResults['analytics'];
       flutterUsage.enabled = value;
       printStatus('Analytics reporting ${value ? 'enabled' : 'disabled'}.');
     }

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

@@ -69,21 +69,21 @@ class CreateCommand extends FlutterCommand {
 
     await Cache.instance.updateAll();
 
-    String flutterRoot = fs.path.absolute(Cache.flutterRoot);
+    final String flutterRoot = fs.path.absolute(Cache.flutterRoot);
 
-    String flutterPackagesDirectory = fs.path.join(flutterRoot, 'packages');
-    String flutterPackagePath = fs.path.join(flutterPackagesDirectory, 'flutter');
+    final String flutterPackagesDirectory = fs.path.join(flutterRoot, 'packages');
+    final String flutterPackagePath = fs.path.join(flutterPackagesDirectory, 'flutter');
     if (!fs.isFileSync(fs.path.join(flutterPackagePath, 'pubspec.yaml')))
       throwToolExit('Unable to find package:flutter in $flutterPackagePath', exitCode: 2);
 
-    String flutterDriverPackagePath = fs.path.join(flutterRoot, 'packages', 'flutter_driver');
+    final String flutterDriverPackagePath = fs.path.join(flutterRoot, 'packages', 'flutter_driver');
     if (!fs.isFileSync(fs.path.join(flutterDriverPackagePath, 'pubspec.yaml')))
       throwToolExit('Unable to find package:flutter_driver in $flutterDriverPackagePath', exitCode: 2);
 
-    Directory projectDir = fs.directory(argResults.rest.first);
-    String dirPath = fs.path.normalize(projectDir.absolute.path);
-    String relativePath = fs.path.relative(dirPath);
-    String projectName = _normalizeProjectName(fs.path.basename(dirPath));
+    final Directory projectDir = fs.directory(argResults.rest.first);
+    final String dirPath = fs.path.normalize(projectDir.absolute.path);
+    final String relativePath = fs.path.relative(dirPath);
+    final String projectName = _normalizeProjectName(fs.path.basename(dirPath));
 
     String error =_validateProjectDir(dirPath, flutterRoot: flutterRoot);
     if (error != null)
@@ -93,7 +93,7 @@ class CreateCommand extends FlutterCommand {
     if (error != null)
       throwToolExit(error);
 
-    int generatedCount = _renderTemplates(
+    final int generatedCount = _renderTemplates(
       projectName,
       argResults['description'],
       dirPath,
@@ -148,7 +148,7 @@ Your main program file is lib/main.dart in the $relativePath directory.
 
     printStatus('Creating project ${fs.path.relative(dirPath)}...');
 
-    Map<String, dynamic> templateContext = <String, dynamic>{
+    final Map<String, dynamic> templateContext = <String, dynamic>{
       'projectName': projectName,
       'androidIdentifier': _createAndroidIdentifier(projectName),
       'iosIdentifier': _createUTIIdentifier(projectName),
@@ -161,7 +161,7 @@ Your main program file is lib/main.dart in the $relativePath directory.
 
     templateContext['withDriverTest'] = renderDriverTest;
 
-    Template createTemplate = new Template.fromName('create');
+    final Template createTemplate = new Template.fromName('create');
     fileCount += createTemplate.render(
       fs.directory(dirPath),
       templateContext, overwriteExisting: false,
@@ -169,7 +169,7 @@ Your main program file is lib/main.dart in the $relativePath directory.
     );
 
     if (renderDriverTest) {
-      Template driverTemplate = new Template.fromName('driver');
+      final Template driverTemplate = new Template.fromName('driver');
       fileCount += driverTemplate.render(fs.directory(fs.path.join(dirPath, 'test_driver')),
           templateContext, overwriteExisting: false);
     }
@@ -192,7 +192,7 @@ String _createAndroidIdentifier(String name) {
 
 String _createUTIIdentifier(String name) {
   // Create a UTI (https://en.wikipedia.org/wiki/Uniform_Type_Identifier) from a base name
-  RegExp disallowed = new RegExp(r"[^a-zA-Z0-9\-\.\u0080-\uffff]+");
+  final RegExp disallowed = new RegExp(r"[^a-zA-Z0-9\-\.\u0080-\uffff]+");
   name = camelCase(name).replaceAll(disallowed, '');
   name = name.isEmpty ? 'untitled' : name;
   return 'com.yourcompany.$name';
@@ -236,7 +236,7 @@ String _validateProjectDir(String dirPath, { String flutterRoot }) {
       "Target directory '$dirPath' is within the Flutter SDK at '$flutterRoot'.";
   }
 
-  FileSystemEntityType type = fs.typeSync(dirPath);
+  final FileSystemEntityType type = fs.typeSync(dirPath);
 
   if (type != FileSystemEntityType.NOT_FOUND) {
     switch(type) {
@@ -253,7 +253,7 @@ String _validateProjectDir(String dirPath, { String flutterRoot }) {
 }
 
 String _relativePath({ String from, String to }) {
-  String result = fs.path.relative(to, from: from);
+  final String result = fs.path.relative(to, from: from);
   // `fs.path.relative()` doesn't always return a correct result: dart-lang/path#12.
   if (fs.isDirectorySync(fs.path.join(from, result)))
     return result;

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

@@ -27,7 +27,7 @@ class DevicesCommand extends FlutterCommand {
         exitCode: 1);
     }
 
-    List<Device> devices = await deviceManager.getAllConnectedDevices();
+    final List<Device> devices = await deviceManager.getAllConnectedDevices();
 
     if (devices.isEmpty) {
       printStatus(

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

@@ -85,7 +85,7 @@ class DriveCommand extends RunCommandBase {
 
   @override
   Future<Null> runCommand() async {
-    String testFile = _getTestFile();
+    final String testFile = _getTestFile();
     if (testFile == null)
       throwToolExit(null);
 
@@ -110,7 +110,7 @@ class DriveCommand extends RunCommandBase {
         );
       }
 
-      LaunchResult result = await appStarter(this);
+      final LaunchResult result = await appStarter(this);
       if (result == null)
         throwToolExit('Application failed to start. Will not run test. Quitting.', exitCode: 1);
       observatoryUri = result.observatoryUri.toString();
@@ -141,7 +141,7 @@ class DriveCommand extends RunCommandBase {
     String appFile = fs.path.normalize(targetFile);
 
     // This command extends `flutter start` and therefore CWD == package dir
-    String packageDir = fs.currentDirectory.path;
+    final String packageDir = fs.currentDirectory.path;
 
     // Make appFile path relative to package directory because we are looking
     // for the corresponding test file relative to it.
@@ -156,7 +156,7 @@ class DriveCommand extends RunCommandBase {
       appFile = fs.path.relative(appFile, from: packageDir);
     }
 
-    List<String> parts = fs.path.split(appFile);
+    final List<String> parts = fs.path.split(appFile);
 
     if (parts.length < 2) {
       printError(
@@ -169,7 +169,7 @@ class DriveCommand extends RunCommandBase {
     // Look for the test file inside `test_driver/` matching the sub-path, e.g.
     // if the application is `lib/foo/bar.dart`, the test file is expected to
     // be `test_driver/foo/bar_test.dart`.
-    String pathWithNoExtension = fs.path.withoutExtension(fs.path.joinAll(
+    final String pathWithNoExtension = fs.path.withoutExtension(fs.path.joinAll(
       <String>[packageDir, 'test_driver']..addAll(parts.skip(1))));
     return '${pathWithNoExtension}_test${fs.path.extension(appFile)}';
   }
@@ -183,7 +183,7 @@ void restoreTargetDeviceFinder() {
 }
 
 Future<Device> findTargetDevice() async {
-  List<Device> devices = await deviceManager.getDevices();
+  final List<Device> devices = await deviceManager.getDevices();
 
   if (deviceManager.hasSpecifiedDeviceId) {
     if (devices.isEmpty) {
@@ -203,7 +203,7 @@ Future<Device> findTargetDevice() async {
     // On Mac we look for the iOS Simulator. If available, we use that. Then
     // we look for an Android device. If there's one, we use that. Otherwise,
     // we launch a new iOS Simulator.
-    Device reusableDevice = devices.firstWhere(
+    final Device reusableDevice = devices.firstWhere(
       (Device d) => d.isLocalEmulator,
       orElse: () {
         return devices.firstWhere((Device d) => d is AndroidDevice,
@@ -218,7 +218,7 @@ Future<Device> findTargetDevice() async {
 
     // No running emulator found. Attempt to start one.
     printStatus('Starting iOS Simulator, because did not find existing connected devices.');
-    bool started = await SimControl.instance.boot();
+    final bool started = await SimControl.instance.boot();
     if (started) {
       return IOSSimulatorUtils.instance.getAttachedDevices().first;
     } else {
@@ -251,7 +251,7 @@ void restoreAppStarter() {
 }
 
 Future<LaunchResult> _startApp(DriveCommand command) async {
-  String mainPath = findMainDartFile(command.targetFile);
+  final String mainPath = findMainDartFile(command.targetFile);
   if (await fs.type(mainPath) != FileSystemEntityType.FILE) {
     printError('Tried to run $mainPath, but that file does not exist.');
     return null;
@@ -261,13 +261,13 @@ Future<LaunchResult> _startApp(DriveCommand command) async {
   await appStopper(command);
 
   printTrace('Installing application package.');
-  ApplicationPackage package = command.applicationPackages
+  final ApplicationPackage package = command.applicationPackages
       .getPackageForPlatform(command.device.platform);
   if (command.device.isAppInstalled(package))
     command.device.uninstallApp(package);
   command.device.installApp(package);
 
-  Map<String, dynamic> platformArgs = <String, dynamic>{};
+  final Map<String, dynamic> platformArgs = <String, dynamic>{};
   if (command.traceStartup)
     platformArgs['trace-startup'] = command.traceStartup;
 
@@ -280,7 +280,7 @@ Future<LaunchResult> _startApp(DriveCommand command) async {
       .logLines
       .listen(printStatus);
 
-  LaunchResult result = await command.device.startApp(
+  final LaunchResult result = await command.device.startApp(
     package,
     command.getBuildMode(),
     mainPath: mainPath,
@@ -313,11 +313,11 @@ Future<Null> _runTests(List<String> testArgs, String observatoryUri) async {
   printTrace('Running driver tests.');
 
   PackageMap.globalPackagesPath = fs.path.normalize(fs.path.absolute(PackageMap.globalPackagesPath));
-  List<String> args = testArgs.toList()
+  final List<String> args = testArgs.toList()
     ..add('--packages=${PackageMap.globalPackagesPath}')
     ..add('-rexpanded');
-  String dartVmPath = fs.path.join(dartSdkPath, 'bin', 'dart');
-  int result = await runCommandAndStreamOutput(
+  final String dartVmPath = fs.path.join(dartSdkPath, 'bin', 'dart');
+  final int result = await runCommandAndStreamOutput(
     <String>[dartVmPath]..addAll(args),
     environment: <String, String>{ 'VM_SERVICE_URL': observatoryUri }
   );
@@ -335,8 +335,8 @@ void restoreAppStopper() {
 
 Future<bool> _stopApp(DriveCommand command) async {
   printTrace('Stopping application.');
-  ApplicationPackage package = command.applicationPackages.getPackageForPlatform(command.device.platform);
-  bool stopped = await command.device.stopApp(package);
+  final ApplicationPackage package = command.applicationPackages.getPackageForPlatform(command.device.platform);
+  final bool stopped = await command.device.stopApp(package);
   await command._deviceLogSubscription?.cancel();
   return stopped;
 }

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

@@ -36,9 +36,9 @@ class FormatCommand extends FlutterCommand {
       );
     }
 
-    String dartfmt = fs.path.join(Cache.flutterRoot, 'bin', 'cache', 'dart-sdk', 'bin', 'dartfmt');
-    List<String> cmd = <String>[dartfmt, '-w']..addAll(argResults.rest);
-    int result = await runCommandAndStreamOutput(cmd);
+    final String dartfmt = fs.path.join(Cache.flutterRoot, 'bin', 'cache', 'dart-sdk', 'bin', 'dartfmt');
+    final List<String> cmd = <String>[dartfmt, '-w']..addAll(argResults.rest);
+    final int result = await runCommandAndStreamOutput(cmd);
     if (result != 0)
       throwToolExit('Formatting failed: $result', exitCode: result);
   }

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

@@ -31,7 +31,7 @@ class InstallCommand extends FlutterCommand {
 
   @override
   Future<Null> runCommand() async {
-    ApplicationPackage package = applicationPackages.getPackageForPlatform(device.platform);
+    final ApplicationPackage package = applicationPackages.getPackageForPlatform(device.platform);
 
     Cache.releaseLockEarly();
 

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

@@ -42,16 +42,16 @@ class LogsCommand extends FlutterCommand {
     if (argResults['clear'])
       device.clearLogs();
 
-    DeviceLogReader logReader = device.getLogReader();
+    final DeviceLogReader logReader = device.getLogReader();
 
     Cache.releaseLockEarly();
 
     printStatus('Showing $logReader logs:');
 
-    Completer<int> exitCompleter = new Completer<int>();
+    final Completer<int> exitCompleter = new Completer<int>();
 
     // Start reading.
-    StreamSubscription<String> subscription = logReader.logLines.listen(
+    final StreamSubscription<String> subscription = logReader.logLines.listen(
       printStatus,
       onDone: () {
         exitCompleter.complete(0);
@@ -75,7 +75,7 @@ class LogsCommand extends FlutterCommand {
     }
 
     // Wait for the log reader to be finished.
-    int result = await exitCompleter.future;
+    final int result = await exitCompleter.future;
     subscription.cancel();
     if (result != 0)
       throwToolExit('Error listening to $logReader logs.');

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

@@ -56,7 +56,7 @@ class PackagesGetCommand extends FlutterCommand {
     if (argResults.rest.length > 1)
       throwToolExit('Too many arguments.\n$usage');
 
-    String target = findProjectRoot(
+    final String target = findProjectRoot(
         argResults.rest.length == 1 ? argResults.rest[0] : null);
     if (target == null)
       throwToolExit(

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

@@ -148,7 +148,7 @@ class RunCommand extends RunCommandBase {
 
   @override
   String get usagePath {
-    String command = shouldUseHotMode() ? 'hotrun' : name;
+    final String command = shouldUseHotMode() ? 'hotrun' : name;
 
     if (device == null)
       return command;
@@ -180,7 +180,7 @@ class RunCommand extends RunCommandBase {
   }
 
   bool shouldUseHotMode() {
-    bool hotArg = argResults['hot'] ?? false;
+    final bool hotArg = argResults['hot'] ?? false;
     final bool shouldUseHotMode = hotArg;
     return (getBuildMode() == BuildMode.debug) && shouldUseHotMode;
   }
@@ -209,7 +209,7 @@ class RunCommand extends RunCommandBase {
     final bool hotMode = shouldUseHotMode();
 
     if (argResults['machine']) {
-      Daemon daemon = new Daemon(stdinCommandStream, stdoutCommandResponse,
+      final Daemon daemon = new Daemon(stdinCommandStream, stdoutCommandResponse,
           notifyingLogger: new NotifyingLogger(), logToStdout: true);
       AppInstance app;
       try {
@@ -223,7 +223,7 @@ class RunCommand extends RunCommandBase {
       } catch (error) {
         throwToolExit(error.toString());
       }
-      int result = await app.runner.waitForAppToFinish();
+      final int result = await app.runner.waitForAppToFinish();
       if (result != 0)
         throwToolExit(null, exitCode: result);
       return null;
@@ -250,7 +250,7 @@ class RunCommand extends RunCommandBase {
         throwToolExit('Hot mode is not supported by this device. Run with --no-hot.');
     }
 
-    String pidFile = argResults['pid-file'];
+    final String pidFile = argResults['pid-file'];
     if (pidFile != null) {
       // Write our pid to the file.
       fs.file(pidFile).writeAsStringSync(pid.toString());
@@ -281,7 +281,7 @@ class RunCommand extends RunCommandBase {
       );
     }
 
-    int result = await runner.run(
+    final int result = await runner.run(
       route: route,
       shouldBuild: !runningWithPrebuiltApplication && argResults['build'],
     );

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

@@ -92,7 +92,7 @@ class ScreenshotCommand extends FlutterCommand {
   }
 
   Future<Null> runSkia(File outputFile) async {
-    Uri skpUri = new Uri(scheme: 'http', host: '127.0.0.1',
+    final Uri skpUri = new Uri(scheme: 'http', host: '127.0.0.1',
         port: int.parse(argResults[_kSkia]),
         path: '/skp');
 
@@ -108,28 +108,28 @@ class ScreenshotCommand extends FlutterCommand {
       throwToolExit('Skia screenshot failed: $skpUri\n$e\n\n$errorHelpText');
     }
     if (skpResponse.statusCode != HttpStatus.OK) {
-      String error = await skpResponse.stream.toStringStream().join();
+      final String error = await skpResponse.stream.toStringStream().join();
       throwToolExit('Error: $error\n\n$errorHelpText');
     }
 
     if (argResults[_kSkiaServe] != null) {
-      Uri skiaserveUri = Uri.parse(argResults[_kSkiaServe]);
-      Uri postUri = new Uri.http(skiaserveUri.authority, '/new');
-      http.MultipartRequest postRequest = new http.MultipartRequest('POST', postUri);
+      final Uri skiaserveUri = Uri.parse(argResults[_kSkiaServe]);
+      final Uri postUri = new Uri.http(skiaserveUri.authority, '/new');
+      final http.MultipartRequest postRequest = new http.MultipartRequest('POST', postUri);
       postRequest.files.add(new http.MultipartFile(
           'file', skpResponse.stream, skpResponse.contentLength));
 
-      http.StreamedResponse postResponse = await postRequest.send();
+      final http.StreamedResponse postResponse = await postRequest.send();
       if (postResponse.statusCode != HttpStatus.OK)
         throwToolExit('Failed to post Skia picture to skiaserve.\n\n$errorHelpText');
     } else {
       outputFile ??= getUniqueFile(fs.currentDirectory, 'flutter', 'skp');
-      IOSink sink = outputFile.openWrite();
+      final IOSink sink = outputFile.openWrite();
       await sink.addStream(skpResponse.stream);
       await sink.close();
       await showOutputFileInfo(outputFile);
       if (await outputFile.length() < 1000) {
-        String content = await outputFile.readAsString();
+        final String content = await outputFile.readAsString();
         if (content.startsWith('{"jsonrpc":"2.0", "error"'))
           throwToolExit('\nIt appears the output file contains an error message, not valid skia output.\n\n$errorHelpText');
       }
@@ -137,7 +137,7 @@ class ScreenshotCommand extends FlutterCommand {
   }
 
   Future<Null> showOutputFileInfo(File outputFile) async {
-    int sizeKB = (await outputFile.length()) ~/ 1024;
+    final int sizeKB = (await outputFile.length()) ~/ 1024;
     printStatus('Screenshot written to ${fs.path.relative(outputFile.path)} (${sizeKB}kB).');
   }
 }

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

@@ -31,9 +31,9 @@ class StopCommand extends FlutterCommand {
 
   @override
   Future<Null> runCommand() async {
-    ApplicationPackage app = applicationPackages.getPackageForPlatform(device.platform);
+    final ApplicationPackage app = applicationPackages.getPackageForPlatform(device.platform);
     if (app == null) {
-      String platformName = getNameForTargetPlatform(device.platform);
+      final String platformName = getNameForTargetPlatform(device.platform);
       throwToolExit('No Flutter application for $platformName found in the current directory.');
     }
     printStatus('Stopping apps on ${device.name}.');

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

@@ -78,7 +78,7 @@ class TestCommand extends FlutterCommand {
   }
 
   Future<int> _runTests(List<String> testArgs, Directory testDirectory) async {
-    Directory currentDirectory = fs.currentDirectory;
+    final Directory currentDirectory = fs.currentDirectory;
     try {
       if (testDirectory != null) {
         printTrace('switching to directory $testDirectory to run tests');
@@ -96,8 +96,8 @@ class TestCommand extends FlutterCommand {
   }
 
   Future<bool> _collectCoverageData(CoverageCollector collector, { bool mergeCoverageData: false }) async {
-    Status status = logger.startProgress('Collecting coverage information...');
-    String coverageData = await collector.finalizeCoverage(
+    final Status status = logger.startProgress('Collecting coverage information...');
+    final String coverageData = await collector.finalizeCoverage(
       timeout: const Duration(seconds: 30),
     );
     status.stop();
@@ -105,13 +105,13 @@ class TestCommand extends FlutterCommand {
     if (coverageData == null)
       return false;
 
-    String coveragePath = argResults['coverage-path'];
-    File coverageFile = fs.file(coveragePath)
+    final String coveragePath = argResults['coverage-path'];
+    final File coverageFile = fs.file(coveragePath)
       ..createSync(recursive: true)
       ..writeAsStringSync(coverageData, flush: true);
     printTrace('wrote coverage data to $coveragePath (size=${coverageData.length})');
 
-    String baseCoverageData = 'coverage/lcov.base.info';
+    final String baseCoverageData = 'coverage/lcov.base.info';
     if (mergeCoverageData) {
       if (!platform.isLinux) {
         printError(
@@ -136,10 +136,10 @@ class TestCommand extends FlutterCommand {
         return false;
       }
 
-      Directory tempDir = fs.systemTempDirectory.createTempSync('flutter_tools');
+      final Directory tempDir = fs.systemTempDirectory.createTempSync('flutter_tools');
       try {
-        File sourceFile = coverageFile.copySync(fs.path.join(tempDir.path, 'lcov.source.info'));
-        ProcessResult result = processManager.runSync(<String>[
+        final File sourceFile = coverageFile.copySync(fs.path.join(tempDir.path, 'lcov.source.info'));
+        final ProcessResult result = processManager.runSync(<String>[
           'lcov',
           '--add-tracefile', baseCoverageData,
           '--add-tracefile', sourceFile.path,
@@ -163,7 +163,7 @@ class TestCommand extends FlutterCommand {
       );
     }
 
-    List<String> testArgs = <String>[];
+    final List<String> testArgs = <String>[];
 
     commandValidator();
 
@@ -208,7 +208,7 @@ class TestCommand extends FlutterCommand {
 
     Cache.releaseLockEarly();
 
-    int result = await _runTests(testArgs, testDir);
+    final int result = await _runTests(testArgs, testDir);
 
     if (collector != null) {
       if (!await _collectCoverageData(collector, mergeCoverageData: argResults['merge-coverage']))

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

@@ -51,11 +51,11 @@ class TraceCommand extends FlutterCommand {
 
   @override
   Future<Null> runCommand() async {
-    int observatoryPort = int.parse(argResults['debug-port']);
+    final int observatoryPort = int.parse(argResults['debug-port']);
 
     // TODO(danrubel): this will break if we move to the new observatory URL
     // See https://github.com/flutter/flutter/issues/7038
-    Uri observatoryUri = Uri.parse('http://127.0.0.1:$observatoryPort');
+    final Uri observatoryUri = Uri.parse('http://127.0.0.1:$observatoryPort');
 
     Tracing tracing;
 
@@ -84,7 +84,7 @@ class TraceCommand extends FlutterCommand {
   }
 
   Future<Null> _stopTracing(Tracing tracing) async {
-    Map<String, dynamic> timeline = await tracing.stopTracingAndDownloadTimeline();
+    final Map<String, dynamic> timeline = await tracing.stopTracingAndDownloadTimeline();
     File localFile;
 
     if (argResults['out'] != null) {
@@ -103,7 +103,7 @@ class Tracing {
   Tracing(this.vmService);
 
   static Tracing connect(Uri uri) {
-    VMService observatory = VMService.connect(uri);
+    final VMService observatory = VMService.connect(uri);
     return new Tracing(observatory);
   }
 
@@ -125,10 +125,10 @@ class Tracing {
       await vmService.vm.setVMTimelineFlags(<String>[]);
       timeline = await vmService.vm.getVMTimeline();
     } else {
-      Completer<Null> whenFirstFrameRendered = new Completer<Null>();
+      final Completer<Null> whenFirstFrameRendered = new Completer<Null>();
 
       vmService.onTimelineEvent.listen((ServiceEvent timelineEvent) {
-        List<Map<String, dynamic>> events = timelineEvent.timelineEvents;
+        final List<Map<String, dynamic>> events = timelineEvent.timelineEvents;
         for (Map<String, dynamic> event in events) {
           if (event['name'] == kFirstUsefulFrameEventName)
             whenFirstFrameRendered.complete();
@@ -159,8 +159,8 @@ class Tracing {
 /// Download the startup trace information from the given observatory client and
 /// store it to build/start_up_info.json.
 Future<Null> downloadStartupTrace(VMService observatory) async {
-  String traceInfoFilePath = fs.path.join(getBuildDirectory(), 'start_up_info.json');
-  File traceInfoFile = fs.file(traceInfoFilePath);
+  final String traceInfoFilePath = fs.path.join(getBuildDirectory(), 'start_up_info.json');
+  final File traceInfoFile = fs.file(traceInfoFilePath);
 
   // Delete old startup data, if any.
   if (await traceInfoFile.exists())
@@ -170,23 +170,23 @@ Future<Null> downloadStartupTrace(VMService observatory) async {
   if (!(await traceInfoFile.parent.exists()))
     await traceInfoFile.parent.create();
 
-  Tracing tracing = new Tracing(observatory);
+  final Tracing tracing = new Tracing(observatory);
 
-  Map<String, dynamic> timeline = await tracing.stopTracingAndDownloadTimeline(
+  final Map<String, dynamic> timeline = await tracing.stopTracingAndDownloadTimeline(
     waitForFirstFrame: true
   );
 
   int extractInstantEventTimestamp(String eventName) {
-    List<Map<String, dynamic>> events = timeline['traceEvents'];
-    Map<String, dynamic> event = events.firstWhere(
+    final List<Map<String, dynamic>> events = timeline['traceEvents'];
+    final Map<String, dynamic> event = events.firstWhere(
       (Map<String, dynamic> event) => event['name'] == eventName, orElse: () => null
     );
     return event == null ? null : event['ts'];
   }
 
-  int engineEnterTimestampMicros = extractInstantEventTimestamp(kFlutterEngineMainEnterEventName);
-  int frameworkInitTimestampMicros = extractInstantEventTimestamp(kFrameworkInitEventName);
-  int firstFrameTimestampMicros = extractInstantEventTimestamp(kFirstUsefulFrameEventName);
+  final int engineEnterTimestampMicros = extractInstantEventTimestamp(kFlutterEngineMainEnterEventName);
+  final int frameworkInitTimestampMicros = extractInstantEventTimestamp(kFrameworkInitEventName);
+  final int firstFrameTimestampMicros = extractInstantEventTimestamp(kFirstUsefulFrameEventName);
 
   if (engineEnterTimestampMicros == null) {
     throw 'Engine start event is missing in the timeline. Cannot compute startup time.';
@@ -196,8 +196,8 @@ Future<Null> downloadStartupTrace(VMService observatory) async {
     throw 'First frame event is missing in the timeline. Cannot compute startup time.';
   }
 
-  int timeToFirstFrameMicros = firstFrameTimestampMicros - engineEnterTimestampMicros;
-  Map<String, dynamic> traceInfo = <String, dynamic>{
+  final int timeToFirstFrameMicros = firstFrameTimestampMicros - engineEnterTimestampMicros;
+  final Map<String, dynamic> traceInfo = <String, dynamic>{
     'engineEnterTimestampMicros': engineEnterTimestampMicros,
     'timeToFirstFrameMicros': timeToFirstFrameMicros,
   };

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

@@ -31,7 +31,7 @@ class UpdatePackagesCommand extends FlutterCommand {
   final bool hidden;
 
   Future<Null> _downloadCoverageData() async {
-    Status status = logger.startProgress("Downloading lcov data for package:flutter...", expectSlowOperation: true);
+    final Status status = logger.startProgress("Downloading lcov data for package:flutter...", expectSlowOperation: true);
     final List<int> data = await fetchUrl(Uri.parse('https://storage.googleapis.com/flutter_infra/flutter/coverage/lcov.info'));
     final String coverageDir = fs.path.join(Cache.flutterRoot, 'packages/flutter/coverage');
     fs.file(fs.path.join(coverageDir, 'lcov.base.info'))

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

@@ -32,7 +32,7 @@ class UpgradeCommand extends FlutterCommand {
       throwToolExit('Unable to upgrade Flutter: no upstream repository configured.');
     }
 
-    FlutterVersion version = new FlutterVersion(Cache.flutterRoot);
+    final FlutterVersion version = new FlutterVersion(Cache.flutterRoot);
     if (version.channel == 'alpha') {
       // The alpha branch is deprecated. Rather than trying to pull the alpha
       // branch, we should switch upstream to master.
@@ -68,7 +68,7 @@ class UpgradeCommand extends FlutterCommand {
     printStatus('');
     printStatus(FlutterVersion.getVersion(Cache.flutterRoot).toString());
 
-    String projRoot = findProjectRoot();
+    final String projRoot = findProjectRoot();
     if (projRoot != null) {
       printStatus('');
       await pubGet(directory: projRoot, upgrade: true, checkLastModified: false);

packages/flutter_tools/lib/src/crash_reporting.dart

@@ -85,20 +85,20 @@ class CrashReportSender {
 
       printStatus('Sending crash report to Google.');
 
-      Uri uri = _baseUri.replace(
+      final Uri uri = _baseUri.replace(
         queryParameters: <String, String>{
           'product': _kProductId,
           'version': flutterVersion,
         },
       );
 
-      _MultipartRequest req = new _MultipartRequest('POST', uri);
+      final _MultipartRequest req = new _MultipartRequest('POST', uri);
       req.fields['product'] = _kProductId;
       req.fields['version'] = flutterVersion;
       req.fields['type'] = _kDartTypeId;
       req.fields['error_runtime_type'] = '${error.runtimeType}';
 
-      Chain chain = stackTrace is StackTrace
+      final Chain chain = stackTrace is StackTrace
           ? new Chain.forTrace(stackTrace)
           : new Chain.parse(stackTrace.toString());
 
@@ -108,10 +108,10 @@ class CrashReportSender {
         filename: _kStackTraceFilename,
       ));
 
-      http.StreamedResponse resp = await _client.send(req);
+      final http.StreamedResponse resp = await _client.send(req);
 
       if (resp.statusCode == 200) {
-        String reportId = await new http.ByteStream(resp.stream)
+        final String reportId = await new http.ByteStream(resp.stream)
             .bytesToString();
         printStatus('Crash report sent (report ID: $reportId)');
       } else {
@@ -225,11 +225,11 @@ class _MultipartRequest extends http.BaseRequest {
   /// that will emit the request body.
   @override
   http.ByteStream finalize() {
-    String boundary = _boundaryString();
+    final String boundary = _boundaryString();
     headers['content-type'] = 'multipart/form-data; boundary=$boundary';
     super.finalize();
 
-    StreamController<List<int>> controller = new StreamController<List<int>>(sync: true);
+    final StreamController<List<int>> controller = new StreamController<List<int>>(sync: true);
 
     void writeAscii(String string) {
       controller.add(UTF8.encode(string));
@@ -369,8 +369,8 @@ class _MultipartRequest extends http.BaseRequest {
 
   /// Returns a randomly-generated multipart boundary string
   String _boundaryString() {
-    String prefix = "dart-";
-    List<int> list = new List<int>.generate(_BOUNDARY_LENGTH - prefix.length,
+    final String prefix = "dart-";
+    final List<int> list = new List<int>.generate(_BOUNDARY_LENGTH - prefix.length,
             (int index) =>
         _BOUNDARY_CHARACTERS[_random.nextInt(_BOUNDARY_CHARACTERS.length)],
         growable: false);
@@ -382,7 +382,7 @@ class _MultipartRequest extends http.BaseRequest {
 /// [stream] is done. Unlike [store], [sink] remains open after [stream] is
 /// done.
 Future<Null> writeStreamToSink<O, I extends O>(Stream<I> stream, EventSink<O> sink) {
-  Completer<Null> completer = new Completer<Null>();
+  final Completer<Null> completer = new Completer<Null>();
   stream.listen(sink.add,
       onError: sink.addError,
       onDone: () => completer.complete());

packages/flutter_tools/lib/src/dart/analysis.dart

@@ -50,8 +50,8 @@ class AnalysisDriver {
   }
 
   List<AnalysisErrorDescription> analyze(Iterable<File> files) {
-    List<AnalysisErrorInfo> infos = _analyze(files);
-    List<AnalysisErrorDescription> errors = <AnalysisErrorDescription>[];
+    final List<AnalysisErrorInfo> infos = _analyze(files);
+    final List<AnalysisErrorDescription> errors = <AnalysisErrorDescription>[];
     for (AnalysisErrorInfo info in infos) {
       for (AnalysisError error in info.errors) {
         if (!_isFiltered(error))
@@ -65,17 +65,17 @@ class AnalysisDriver {
     context = AnalysisEngine.instance.createAnalysisContext();
     _processAnalysisOptions();
     context.analysisOptions = options;
-    PackageInfo packageInfo = new PackageInfo(options.packageMap);
-    List<UriResolver> resolvers = _getResolvers(context, packageInfo.asMap());
+    final PackageInfo packageInfo = new PackageInfo(options.packageMap);
+    final List<UriResolver> resolvers = _getResolvers(context, packageInfo.asMap());
     context.sourceFactory =
         new SourceFactory(resolvers, packageInfo.asPackages());
 
-    List<Source> sources = <Source>[];
-    ChangeSet changeSet = new ChangeSet();
+    final List<Source> sources = <Source>[];
+    final ChangeSet changeSet = new ChangeSet();
     for (File file in files) {
-      JavaFile sourceFile = new JavaFile(fs.path.normalize(file.absolute.path));
+      final JavaFile sourceFile = new JavaFile(fs.path.normalize(file.absolute.path));
       Source source = new FileBasedSource(sourceFile, sourceFile.toURI());
-      Uri uri = context.sourceFactory.restoreUri(source);
+      final Uri uri = context.sourceFactory.restoreUri(source);
       if (uri != null) {
         source = new FileBasedSource(sourceFile, uri);
       }
@@ -84,7 +84,7 @@ class AnalysisDriver {
     }
     context.applyChanges(changeSet);
 
-    List<AnalysisErrorInfo> infos = <AnalysisErrorInfo>[];
+    final List<AnalysisErrorInfo> infos = <AnalysisErrorInfo>[];
     for (Source source in sources) {
       context.computeErrors(source);
       infos.add(context.getErrors(source));
@@ -98,13 +98,13 @@ class AnalysisDriver {
       Map<String, List<file_system.Folder>> packageMap) {
 
     // Create our list of resolvers.
-    List<UriResolver> resolvers = <UriResolver>[];
+    final List<UriResolver> resolvers = <UriResolver>[];
 
     // Look for an embedder.
-    EmbedderYamlLocator locator = new EmbedderYamlLocator(packageMap);
+    final EmbedderYamlLocator locator = new EmbedderYamlLocator(packageMap);
     if (locator.embedderYamls.isNotEmpty) {
       // Create and configure an embedded SDK.
-      EmbedderSdk sdk = new EmbedderSdk(PhysicalResourceProvider.INSTANCE, locator.embedderYamls);
+      final EmbedderSdk sdk = new EmbedderSdk(PhysicalResourceProvider.INSTANCE, locator.embedderYamls);
       // Fail fast if no URI mappings are found.
       assert(sdk.libraryMap.size() > 0);
       sdk.analysisOptions = context.analysisOptions;
@@ -112,7 +112,7 @@ class AnalysisDriver {
       resolvers.add(new DartUriResolver(sdk));
     } else {
       // Fall back to a standard SDK if no embedder is found.
-      FolderBasedDartSdk sdk = new FolderBasedDartSdk(resourceProvider,
+      final FolderBasedDartSdk sdk = new FolderBasedDartSdk(resourceProvider,
           PhysicalResourceProvider.INSTANCE.getFolder(sdkDir));
       sdk.analysisOptions = context.analysisOptions;
 
@@ -120,11 +120,11 @@ class AnalysisDriver {
     }
 
     if (options.packageRootPath != null) {
-      ContextBuilderOptions builderOptions = new ContextBuilderOptions();
+      final ContextBuilderOptions builderOptions = new ContextBuilderOptions();
       builderOptions.defaultPackagesDirectoryPath = options.packageRootPath;
-      ContextBuilder builder = new ContextBuilder(resourceProvider, null, null,
+      final ContextBuilder builder = new ContextBuilder(resourceProvider, null, null,
           options: builderOptions);
-      PackageMapUriResolver packageUriResolver = new PackageMapUriResolver(resourceProvider,
+      final PackageMapUriResolver packageUriResolver = new PackageMapUriResolver(resourceProvider,
           builder.convertPackagesToMap(builder.createPackageMap('')));
 
       resolvers.add(packageUriResolver);
@@ -135,17 +135,17 @@ class AnalysisDriver {
   }
 
   bool _isFiltered(AnalysisError error) {
-    ErrorProcessor processor = ErrorProcessor.getProcessor(context.analysisOptions, error);
+    final ErrorProcessor processor = ErrorProcessor.getProcessor(context.analysisOptions, error);
     // Filtered errors are processed to a severity of `null`.
     return processor != null && processor.severity == null;
   }
 
   void _processAnalysisOptions() {
-    String optionsPath = options.analysisOptionsFile;
+    final String optionsPath = options.analysisOptionsFile;
     if (optionsPath != null) {
-      file_system.File file =
+      final file_system.File file =
            PhysicalResourceProvider.INSTANCE.getFile(optionsPath);
-      Map<Object, Object> optionMap =
+      final Map<Object, Object> optionMap =
           analysisOptionsProvider.getOptionsFromFile(file);
       if (optionMap != null)
         applyToAnalysisOptions(options, optionMap);
@@ -153,9 +153,9 @@ class AnalysisDriver {
   }
 
   void _processPlugins() {
-    List<Plugin> plugins = <Plugin>[];
+    final List<Plugin> plugins = <Plugin>[];
     plugins.addAll(AnalysisEngine.instance.requiredPlugins);
-    ExtensionManager manager = new ExtensionManager();
+    final ExtensionManager manager = new ExtensionManager();
     manager.processPlugins(plugins);
     linter.registerLintRules();
   }
@@ -181,7 +181,7 @@ class AnalysisErrorDescription {
   ErrorCode get errorCode => error.errorCode;
 
   String get errorType {
-    ErrorSeverity severity = errorCode.errorSeverity;
+    final ErrorSeverity severity = errorCode.errorSeverity;
     if (severity == ErrorSeverity.INFO) {
       if (errorCode.type == ErrorType.HINT || errorCode.type == ErrorType.LINT)
         return errorCode.type.displayName;
@@ -231,9 +231,9 @@ class DriverOptions extends AnalysisOptionsImpl {
 
 class PackageInfo {
   PackageInfo(Map<String, String> packageMap) {
-    Map<String, Uri> packages = new HashMap<String, Uri>();
+    final Map<String, Uri> packages = new HashMap<String, Uri>();
     for (String package in packageMap.keys) {
-      String path = packageMap[package];
+      final String path = packageMap[package];
       packages[package] = new Uri.directory(path);
       _map[package] = <file_system.Folder>[
         PhysicalResourceProvider.INSTANCE.getFolder(path)

packages/flutter_tools/lib/src/dart/dependencies.dart

@@ -35,7 +35,7 @@ class DartDependencySetBuilder {
       mainScriptPath
     ];
 
-    String output = runSyncAndThrowStdErrOnError(args);
+    final String output = runSyncAndThrowStdErrOnError(args);
 
     return new Set<String>.from(LineSplitter.split(output));
   }
@@ -65,8 +65,8 @@ class _GenSnapshotDartDependencySetBuilder implements DartDependencySetBuilder {
     assert(fs.path.isAbsolute(this.projectRootPath));
 
     // TODO(goderbauer): Implement --print-deps in gen_snapshot so we don't have to parse the Makefile
-    Directory tempDir = fs.systemTempDirectory.createTempSync('dart_dependency_set_builder_');
-    String depfilePath = fs.path.join(tempDir.path, 'snapshot_blob.bin.d');
+    final Directory tempDir = fs.systemTempDirectory.createTempSync('dart_dependency_set_builder_');
+    final String depfilePath = fs.path.join(tempDir.path, 'snapshot_blob.bin.d');
 
     final List<String> args = <String>[
       snapshotterPath,
@@ -84,14 +84,14 @@ class _GenSnapshotDartDependencySetBuilder implements DartDependencySetBuilder {
     String output = fs.file(depfilePath).readAsStringSync();
     tempDir.deleteSync(recursive: true);
 
-    int splitIndex = output.indexOf(':');
+    final int splitIndex = output.indexOf(':');
     if (splitIndex == -1)
       throw new Exception('Unexpected output $output');
 
     output = output.substring(splitIndex + 1);
     // Note: next line means we cannot process anything with spaces in the path
     //       because Makefiles don't support spaces in paths :(
-    List<String> depsList = output.trim().split(' ');
+    final List<String> depsList = output.trim().split(' ');
     return new Set<String>.from(depsList);
   }
 }

packages/flutter_tools/lib/src/dart/package_map.dart

@@ -9,7 +9,7 @@ import '../base/file_system.dart';
 const String kPackagesFileName = '.packages';
 
 Map<String, Uri> _parse(String packagesPath) {
-  List<int> source = fs.file(packagesPath).readAsBytesSync();
+  final List<int> source = fs.file(packagesPath).readAsBytesSync();
   return packages_file.parse(source, new Uri.file(packagesPath));
 }
 
@@ -42,10 +42,10 @@ class PackageMap {
   /// Returns the path to [packageUri].
   String pathForPackage(Uri packageUri) {
     assert(packageUri.scheme == 'package');
-    List<String> pathSegments = packageUri.pathSegments.toList();
-    String packageName = pathSegments.removeAt(0);
-    Uri packageBase = map[packageName];
-    String packageRelativePath = fs.path.joinAll(pathSegments);
+    final List<String> pathSegments = packageUri.pathSegments.toList();
+    final String packageName = pathSegments.removeAt(0);
+    final Uri packageBase = map[packageName];
+    final String packageRelativePath = fs.path.joinAll(pathSegments);
     return packageBase.resolve(packageRelativePath).path;
   }
 
@@ -53,7 +53,7 @@ class PackageMap {
     if (fs.isFileSync(packagesPath))
       return null;
     String message = '$packagesPath does not exist.';
-    String pubspecPath = fs.path.absolute(fs.path.dirname(packagesPath), 'pubspec.yaml');
+    final String pubspecPath = fs.path.absolute(fs.path.dirname(packagesPath), 'pubspec.yaml');
     if (fs.isFileSync(pubspecPath))
       message += '\nDid you run "flutter packages get" in this directory?';
     else

packages/flutter_tools/lib/src/dart/pub.dart

@@ -15,10 +15,10 @@ import 'sdk.dart';
 bool _shouldRunPubGet({ File pubSpecYaml, File dotPackages }) {
   if (!dotPackages.existsSync())
     return true;
-  DateTime dotPackagesLastModified = dotPackages.lastModifiedSync();
+  final DateTime dotPackagesLastModified = dotPackages.lastModifiedSync();
   if (pubSpecYaml.lastModifiedSync().isAfter(dotPackagesLastModified))
     return true;
-  File flutterToolsStamp = Cache.instance.getStampFileFor('flutter_tools');
+  final File flutterToolsStamp = Cache.instance.getStampFileFor('flutter_tools');
   if (flutterToolsStamp.existsSync() &&
       flutterToolsStamp.lastModifiedSync().isAfter(dotPackagesLastModified))
     return true;
@@ -34,8 +34,8 @@ Future<Null> pubGet({
   if (directory == null)
     directory = fs.currentDirectory.path;
 
-  File pubSpecYaml = fs.file(fs.path.join(directory, 'pubspec.yaml'));
-  File dotPackages = fs.file(fs.path.join(directory, '.packages'));
+  final File pubSpecYaml = fs.file(fs.path.join(directory, 'pubspec.yaml'));
+  final File dotPackages = fs.file(fs.path.join(directory, '.packages'));
 
   if (!pubSpecYaml.existsSync()) {
     if (!skipIfAbsent)
@@ -44,10 +44,10 @@ Future<Null> pubGet({
   }
 
   if (!checkLastModified || _shouldRunPubGet(pubSpecYaml: pubSpecYaml, dotPackages: dotPackages)) {
-    String command = upgrade ? 'upgrade' : 'get';
-    Status status = logger.startProgress("Running 'flutter packages $command' in ${fs.path.basename(directory)}...",
+    final String command = upgrade ? 'upgrade' : 'get';
+    final Status status = logger.startProgress("Running 'flutter packages $command' in ${fs.path.basename(directory)}...",
         expectSlowOperation: true);
-    int code = await runCommandAndStreamOutput(
+    final int code = await runCommandAndStreamOutput(
       <String>[sdkBinaryName('pub'), '--verbosity=warning', command, '--no-packages-dir', '--no-precompile'],
       workingDirectory: directory,
       mapFunction: _filterOverrideWarnings,

packages/flutter_tools/lib/src/dependency_checker.dart

@@ -34,8 +34,8 @@ class DependencyChecker {
 
     // Check all dependency modification times.
     for (String path in _dependencies) {
-      File file = fs.file(path);
-      FileStat stat = file.statSync();
+      final File file = fs.file(path);
+      final FileStat stat = file.statSync();
       if (stat.type == FileSystemEntityType.NOT_FOUND) {
         printTrace('DependencyChecker: Error stating $path.');
         return true;

packages/flutter_tools/lib/src/devfs.dart

@@ -72,8 +72,8 @@ class DevFSFileContent extends DevFSContent {
     _fileStat = file.statSync();
     if (_fileStat.type == FileSystemEntityType.LINK) {
       // Resolve, stat, and maybe cache the symlink target.
-      String resolved = file.resolveSymbolicLinksSync();
-      FileSystemEntity linkTarget = fs.file(resolved);
+      final String resolved = file.resolveSymbolicLinksSync();
+      final FileSystemEntity linkTarget = fs.file(resolved);
       // Stat the link target.
       _fileStat = linkTarget.statSync();
       if (devFSConfig.cacheSymlinks) {
@@ -84,7 +84,7 @@ class DevFSFileContent extends DevFSContent {
 
   @override
   bool get isModified {
-    FileStat _oldFileStat = _fileStat;
+    final FileStat _oldFileStat = _fileStat;
     _stat();
     return _oldFileStat == null || _fileStat.modified.isAfter(_oldFileStat.modified);
   }
@@ -121,7 +121,7 @@ class DevFSByteContent extends DevFSContent {
   /// Return `true` only once so that the content is written to the device only once.
   @override
   bool get isModified {
-    bool modified = _isModified;
+    final bool modified = _isModified;
     _isModified = false;
     return modified;
   }
@@ -173,7 +173,7 @@ class ServiceProtocolDevFSOperations implements DevFSOperations {
 
   @override
   Future<Uri> create(String fsName) async {
-    Map<String, dynamic> response = await vmService.vm.createDevFS(fsName);
+    final Map<String, dynamic> response = await vmService.vm.createDevFS(fsName);
     return Uri.parse(response['uri']);
   }
 
@@ -193,7 +193,7 @@ class ServiceProtocolDevFSOperations implements DevFSOperations {
     } catch (e) {
       return e;
     }
-    String fileContents = BASE64.encode(bytes);
+    final String fileContents = BASE64.encode(bytes);
     try {
       return await vmService.vm.invokeRpcRaw(
         '_writeDevFSFile',
@@ -251,8 +251,8 @@ class _DevFSHttpWriter {
         // Finished.
         break;
       }
-      Uri deviceUri = _outstanding.keys.first;
-      DevFSContent content = _outstanding.remove(deviceUri);
+      final Uri deviceUri = _outstanding.keys.first;
+      final DevFSContent content = _outstanding.remove(deviceUri);
       _scheduleWrite(deviceUri, content, progressReporter);
       _inFlight++;
     }
@@ -265,15 +265,15 @@ class _DevFSHttpWriter {
     int retry = 0,
   ]) async {
     try {
-      HttpClientRequest request = await _client.putUrl(httpAddress);
+      final HttpClientRequest request = await _client.putUrl(httpAddress);
       request.headers.removeAll(HttpHeaders.ACCEPT_ENCODING);
       request.headers.add('dev_fs_name', fsName);
       // TODO(goderbauer): transfer real Uri (instead of file path) when remote end supports it
       request.headers.add('dev_fs_path_b64',
                           BASE64.encode(UTF8.encode(deviceUri.toFilePath(windows: false))));
-      Stream<List<int>> contents = content.contentsAsCompressedStream();
+      final Stream<List<int>> contents = content.contentsAsCompressedStream();
       await request.addStream(contents);
-      HttpClientResponse response = await request.close();
+      final HttpClientResponse response = await request.close();
       await response.drain<Null>();
     } catch (e) {
       if (retry < kMaxRetries) {
@@ -375,17 +375,17 @@ class DevFS {
 
     // Handle deletions.
     printTrace('Scanning for deleted files');
-    String assetBuildDirPrefix = _asUriPath(getAssetBuildDirectory());
+    final String assetBuildDirPrefix = _asUriPath(getAssetBuildDirectory());
     final List<Uri> toRemove = new List<Uri>();
     _entries.forEach((Uri deviceUri, DevFSContent content) {
       if (!content._exists) {
-        Future<Map<String, dynamic>> operation =
+        final Future<Map<String, dynamic>> operation =
             _operations.deleteFile(fsName, deviceUri);
         if (operation != null)
           _pendingOperations.add(operation);
         toRemove.add(deviceUri);
         if (deviceUri.path.startsWith(assetBuildDirPrefix)) {
-          String archivePath = deviceUri.path.substring(assetBuildDirPrefix.length);
+          final String archivePath = deviceUri.path.substring(assetBuildDirPrefix.length);
           assetPathsToEvict.add(archivePath);
         }
       }
@@ -399,7 +399,7 @@ class DevFS {
 
     // Update modified files
     int numBytes = 0;
-    Map<Uri, DevFSContent> dirtyEntries = <Uri, DevFSContent>{};
+    final Map<Uri, DevFSContent> dirtyEntries = <Uri, DevFSContent>{};
     _entries.forEach((Uri deviceUri, DevFSContent content) {
       String archivePath;
       if (deviceUri.path.startsWith(assetBuildDirPrefix))
@@ -423,7 +423,7 @@ class DevFS {
       } else {
         // Make service protocol requests for each.
         dirtyEntries.forEach((Uri deviceUri, DevFSContent content) {
-          Future<Map<String, dynamic>> operation =
+          final Future<Map<String, dynamic>> operation =
               _operations.writeFile(fsName, deviceUri, content);
           if (operation != null)
             _pendingOperations.add(operation);
@@ -449,7 +449,7 @@ class DevFS {
   }
 
   void _scanFile(Uri deviceUri, FileSystemEntity file) {
-    DevFSContent content = _entries.putIfAbsent(deviceUri, () => new DevFSFileContent(file));
+    final DevFSContent content = _entries.putIfAbsent(deviceUri, () => new DevFSFileContent(file));
     content._exists = true;
   }
 
@@ -463,7 +463,7 @@ class DevFS {
   }
 
   bool _shouldIgnore(Uri deviceUri) {
-    List<String> ignoredUriPrefixes = <String>['android/',
+    final List<String> ignoredUriPrefixes = <String>['android/',
                                                _asUriPath(getBuildDirectory()),
                                                'ios/',
                                                '.pub/'];
@@ -480,7 +480,7 @@ class DevFS {
                                bool ignoreDotFiles: true,
                                Set<String> fileFilter}) async {
     if (directoryUriOnDevice == null) {
-      String relativeRootPath = fs.path.relative(directory.path, from: rootDirectory.path);
+      final String relativeRootPath = fs.path.relative(directory.path, from: rootDirectory.path);
       if (relativeRootPath == '.') {
         directoryUriOnDevice = new Uri();
       } else {
@@ -488,7 +488,7 @@ class DevFS {
       }
     }
     try {
-      Stream<FileSystemEntity> files =
+      final Stream<FileSystemEntity> files =
           directory.list(recursive: recursive, followLinks: false);
       await for (FileSystemEntity file in files) {
         if (!devFSConfig.noDirectorySymlinks && (file is Link)) {
@@ -532,12 +532,12 @@ class DevFS {
 
   Future<Null> _scanPackages(Set<String> fileFilter) async {
     StringBuffer sb;
-    PackageMap packageMap = new PackageMap(_packagesFilePath);
+    final PackageMap packageMap = new PackageMap(_packagesFilePath);
 
     for (String packageName in packageMap.map.keys) {
-      Uri packageUri = packageMap.map[packageName];
-      String packagePath = packageUri.toFilePath();
-      Directory packageDirectory = fs.directory(packageUri);
+      final Uri packageUri = packageMap.map[packageName];
+      final String packagePath = packageUri.toFilePath();
+      final Directory packageDirectory = fs.directory(packageUri);
       Uri directoryUriOnDevice = fs.path.toUri(fs.path.join('packages', packageName) + fs.path.separator);
       bool packageExists;
 
@@ -560,7 +560,7 @@ class DevFS {
       }
     }
     if (sb != null) {
-      DevFSContent content = _entries[fs.path.toUri('.packages')];
+      final DevFSContent content = _entries[fs.path.toUri('.packages')];
       if (content is DevFSStringContent && content.string == sb.toString()) {
         content._exists = true;
         return;

packages/flutter_tools/lib/src/device.dart

@@ -42,8 +42,8 @@ class DeviceManager {
   /// This does a case insentitive compare with [deviceId].
   Future<List<Device>> getDevicesById(String deviceId) async {
     deviceId = deviceId.toLowerCase();
-    List<Device> devices = await getAllConnectedDevices();
-    Device device = devices.firstWhere(
+    final List<Device> devices = await getAllConnectedDevices();
+    final Device device = devices.firstWhere(
         (Device device) =>
             device.id.toLowerCase() == deviceId ||
             device.name.toLowerCase() == deviceId,
@@ -250,11 +250,11 @@ abstract class Device {
       return <String>[];
 
     // Extract device information
-    List<List<String>> table = <List<String>>[];
+    final List<List<String>> table = <List<String>>[];
     for (Device device in devices) {
       String supportIndicator = device.isSupported() ? '' : ' (unsupported)';
       if (device.isLocalEmulator) {
-        String type = device.platform == TargetPlatform.ios ? 'simulator' : 'emulator';
+        final String type = device.platform == TargetPlatform.ios ? 'simulator' : 'emulator';
         supportIndicator += ' ($type)';
       }
       table.add(<String>[
@@ -266,7 +266,7 @@ abstract class Device {
     }
 
     // Calculate column widths
-    List<int> indices = new List<int>.generate(table[0].length - 1, (int i) => i);
+    final List<int> indices = new List<int>.generate(table[0].length - 1, (int i) => i);
     List<int> widths = indices.map((int i) => 0).toList();
     for (List<String> row in table) {
       widths = indices.map((int i) => math.max(widths[i], row[i].length)).toList();
@@ -336,7 +336,7 @@ class LaunchResult {
 
   @override
   String toString() {
-    StringBuffer buf = new StringBuffer('started=$started');
+    final StringBuffer buf = new StringBuffer('started=$started');
     if (observatoryUri != null)
       buf.write(', observatory=$observatoryUri');
     if (diagnosticUri != null)

packages/flutter_tools/lib/src/doctor.dart

@@ -28,7 +28,7 @@ const Map<String, String> _osNames = const <String, String>{
 };
 
 String osName() {
-  String os = platform.operatingSystem;
+  final String os = platform.operatingSystem;
   return _osNames.containsKey(os) ? _osNames[os] : os;
 }
 
@@ -59,7 +59,7 @@ class Doctor {
       if (_iosWorkflow.appliesToHostPlatform)
         _validators.add(_iosWorkflow);
 
-      List<DoctorValidator> ideValidators = <DoctorValidator>[];
+      final List<DoctorValidator> ideValidators = <DoctorValidator>[];
       ideValidators.addAll(AndroidStudioValidator.allValidators);
       ideValidators.addAll(IntelliJValidator.installedValidators);
       if (ideValidators.isNotEmpty)
@@ -82,12 +82,12 @@ class Doctor {
   }
 
   Future<String> get summaryText async {
-    StringBuffer buffer = new StringBuffer();
+    final StringBuffer buffer = new StringBuffer();
 
     bool allGood = true;
 
     for (DoctorValidator validator in validators) {
-      ValidationResult result = await validator.validate();
+      final ValidationResult result = await validator.validate();
       buffer.write('${result.leadingBox} ${validator.title} is ');
       if (result.type == ValidationType.missing)
         buffer.write('not installed.');
@@ -123,7 +123,7 @@ class Doctor {
         printStatus('');
       firstLine = false;
 
-      ValidationResult result = await validator.validate();
+      final ValidationResult result = await validator.validate();
 
       if (result.type == ValidationType.missing)
         doctorResult = false;
@@ -134,7 +134,7 @@ class Doctor {
         printStatus('${result.leadingBox} ${validator.title}');
 
       for (ValidationMessage message in result.messages) {
-        String text = message.message.replaceAll('\n', '\n      ');
+        final String text = message.message.replaceAll('\n', '\n      ');
         if (message.isError) {
           printStatus('    ✗ $text', emphasis: true);
         } else {
@@ -211,10 +211,10 @@ class _FlutterValidator extends DoctorValidator {
 
   @override
   Future<ValidationResult> validate() async {
-    List<ValidationMessage> messages = <ValidationMessage>[];
-    ValidationType valid = ValidationType.installed;
+    final List<ValidationMessage> messages = <ValidationMessage>[];
+    final ValidationType valid = ValidationType.installed;
 
-    FlutterVersion version = FlutterVersion.getVersion();
+    final FlutterVersion version = FlutterVersion.getVersion();
 
     messages.add(new ValidationMessage('Flutter at ${version.flutterRoot}'));
     messages.add(new ValidationMessage(
@@ -262,7 +262,7 @@ abstract class IntelliJValidator extends DoctorValidator {
 
   @override
   Future<ValidationResult> validate() async {
-    List<ValidationMessage> messages = <ValidationMessage>[];
+    final List<ValidationMessage> messages = <ValidationMessage>[];
 
     int installCount = 0;
 
@@ -300,25 +300,25 @@ abstract class IntelliJValidator extends DoctorValidator {
       ));
       return false;
     }
-    String version = _readPackageVersion(packageName);
+    final String version = _readPackageVersion(packageName);
     messages.add(new ValidationMessage('$title plugin '
         '${version != null ? "version $version" : "installed"}'));
     return true;
   }
 
   String _readPackageVersion(String packageName) {
-    String jarPath = packageName.endsWith('.jar')
+    final String jarPath = packageName.endsWith('.jar')
         ? fs.path.join(pluginsPath, packageName)
         : fs.path.join(pluginsPath, packageName, 'lib', '$packageName.jar');
     // TODO(danrubel) look for a better way to extract a single 2K file from the zip
     // rather than reading the entire file into memory.
     try {
-      Archive archive = new ZipDecoder().decodeBytes(fs.file(jarPath).readAsBytesSync());
-      ArchiveFile file = archive.findFile('META-INF/plugin.xml');
-      String content = UTF8.decode(file.content);
-      String versionStartTag = '<version>';
-      int start = content.indexOf(versionStartTag);
-      int end = content.indexOf('</version>', start);
+      final Archive archive = new ZipDecoder().decodeBytes(fs.file(jarPath).readAsBytesSync());
+      final ArchiveFile file = archive.findFile('META-INF/plugin.xml');
+      final String content = UTF8.decode(file.content);
+      final String versionStartTag = '<version>';
+      final int start = content.indexOf(versionStartTag);
+      final int end = content.indexOf('</version>', start);
       return content.substring(start + versionStartTag.length, end);
     } catch (_) {
       return null;
@@ -326,7 +326,7 @@ abstract class IntelliJValidator extends DoctorValidator {
   }
 
   bool hasPackage(String packageName) {
-    String packagePath = fs.path.join(pluginsPath, packageName);
+    final String packagePath = fs.path.join(pluginsPath, packageName);
     if (packageName.endsWith('.jar'))
       return fs.isFileSync(packagePath);
     return fs.isDirectorySync(packagePath);
@@ -345,14 +345,14 @@ class IntelliJValidatorOnLinuxAndWindows extends IntelliJValidator {
   String pluginsPath;
 
   static Iterable<DoctorValidator> get installed {
-    List<DoctorValidator> validators = <DoctorValidator>[];
+    final List<DoctorValidator> validators = <DoctorValidator>[];
     if (homeDirPath == null) return validators;
 
     void addValidator(String title, String version, String installPath, String pluginsPath) {
-      IntelliJValidatorOnLinuxAndWindows validator =
+      final IntelliJValidatorOnLinuxAndWindows validator =
         new IntelliJValidatorOnLinuxAndWindows(title, version, installPath, pluginsPath);
       for (int index = 0; index < validators.length; ++index) {
-        DoctorValidator other = validators[index];
+        final DoctorValidator other = validators[index];
         if (other is IntelliJValidatorOnLinuxAndWindows && validator.installPath == other.installPath) {
           if (validator.version.compareTo(other.version) > 0)
             validators[index] = validator;
@@ -364,10 +364,10 @@ class IntelliJValidatorOnLinuxAndWindows extends IntelliJValidator {
 
     for (FileSystemEntity dir in fs.directory(homeDirPath).listSync()) {
       if (dir is Directory) {
-        String name = fs.path.basename(dir.path);
+        final String name = fs.path.basename(dir.path);
         IntelliJValidator._idToTitle.forEach((String id, String title) {
           if (name.startsWith('.$id')) {
-            String version = name.substring(id.length + 1);
+            final String version = name.substring(id.length + 1);
             String installPath;
             try {
               installPath = fs.file(fs.path.join(dir.path, 'system', '.home')).readAsStringSync();
@@ -375,7 +375,7 @@ class IntelliJValidatorOnLinuxAndWindows extends IntelliJValidator {
               // ignored
             }
             if (installPath != null && fs.isDirectorySync(installPath)) {
-              String pluginsPath = fs.path.join(dir.path, 'config', 'plugins');
+              final String pluginsPath = fs.path.join(dir.path, 'config', 'plugins');
               addValidator(title, version, installPath, pluginsPath);
             }
           }
@@ -400,21 +400,21 @@ class IntelliJValidatorOnMac extends IntelliJValidator {
   };
 
   static Iterable<DoctorValidator> get installed {
-    List<DoctorValidator> validators = <DoctorValidator>[];
-    List<String> installPaths = <String>['/Applications', fs.path.join(homeDirPath, 'Applications')];
+    final List<DoctorValidator> validators = <DoctorValidator>[];
+    final List<String> installPaths = <String>['/Applications', fs.path.join(homeDirPath, 'Applications')];
 
     void checkForIntelliJ(Directory dir) {
-      String name = fs.path.basename(dir.path);
+      final String name = fs.path.basename(dir.path);
       _dirNameToId.forEach((String dirName, String id) {
         if (name == dirName) {
-          String title = IntelliJValidator._idToTitle[id];
+          final String title = IntelliJValidator._idToTitle[id];
           validators.add(new IntelliJValidatorOnMac(title, id, dir.path));
         }
       });
     }
 
     try {
-      Iterable<FileSystemEntity> installDirs = installPaths
+      final Iterable<FileSystemEntity> installDirs = installPaths
               .map((String installPath) => fs.directory(installPath).listSync())
               .expand((List<FileSystemEntity> mappedDirs) => mappedDirs)
               .where((FileSystemEntity mappedDir) => mappedDir is Directory);
@@ -444,7 +444,7 @@ class IntelliJValidatorOnMac extends IntelliJValidator {
   @override
   String get version {
     if (_version == null) {
-      String plistFile = fs.path.join(installPath, 'Contents', 'Info.plist');
+      final String plistFile = fs.path.join(installPath, 'Contents', 'Info.plist');
       _version = getValueFromFile(plistFile, kCFBundleShortVersionStringKey) ?? 'unknown';
     }
     return _version;
@@ -453,9 +453,9 @@ class IntelliJValidatorOnMac extends IntelliJValidator {
 
   @override
   String get pluginsPath {
-    List<String> split = version.split('.');
-    String major = split[0];
-    String minor = split[1];
+    final List<String> split = version.split('.');
+    final String major = split[0];
+    final String minor = split[1];
     return fs.path.join(homeDirPath, 'Library', 'Application Support', '$id$major.$minor');
   }
 }
@@ -465,7 +465,7 @@ class DeviceValidator extends DoctorValidator {
 
   @override
   Future<ValidationResult> validate() async {
-    List<Device> devices = await deviceManager.getAllConnectedDevices();
+    final List<Device> devices = await deviceManager.getAllConnectedDevices();
     List<ValidationMessage> messages;
     if (devices.isEmpty) {
       messages = <ValidationMessage>[new ValidationMessage('None')];

packages/flutter_tools/lib/src/flx.dart

@@ -59,7 +59,7 @@ Future<int> _createScriptSnapshotWithSkySnapshot({
   assert(mainPath != null);
   assert(snapshotPath != null);
   assert(packages != null);
-  String snapshotterPath = artifacts.getArtifactPath(Artifact.skySnapshot);
+  final String snapshotterPath = artifacts.getArtifactPath(Artifact.skySnapshot);
 
   final List<String> args = <String>[
     snapshotterPath,
@@ -83,9 +83,9 @@ Future<int> _creteScriptSnapshotWithGenSnapshot({
   assert(mainPath != null);
   assert(snapshotPath != null);
   assert(packages != null);
-  String snapshotterPath = artifacts.getArtifactPath(Artifact.genSnapshot);
-  String vmSnapshotData = artifacts.getArtifactPath(Artifact.vmSnapshotData);
-  String isolateSnapshotData = artifacts.getArtifactPath(Artifact.isolateSnapshotData);
+  final String snapshotterPath = artifacts.getArtifactPath(Artifact.genSnapshot);
+  final String vmSnapshotData = artifacts.getArtifactPath(Artifact.vmSnapshotData);
+  final String isolateSnapshotData = artifacts.getArtifactPath(Artifact.isolateSnapshotData);
 
   final List<String> args = <String>[
     snapshotterPath,
@@ -149,7 +149,7 @@ Future<Null> build({
   if (kernelContent != null) {
     // TODO(danrubel) in the future, call the VM to generate this file
     kernelFile = fs.file(kernelPath);
-    IOSink sink = kernelFile.openWrite();
+    final IOSink sink = kernelFile.openWrite();
     await sink.addStream(kernelContent.contentsAsStream());
     sink.close();
   }
@@ -158,7 +158,7 @@ Future<Null> build({
 
     // In a precompiled snapshot, the instruction buffer contains script
     // content equivalents
-    int result = await createSnapshot(
+    final int result = await createSnapshot(
       mainPath: mainPath,
       snapshotPath: snapshotPath,
       depfilePath: depfilePath,
@@ -201,8 +201,8 @@ Future<Null> assemble({
   printTrace('Building $outputPath');
 
   // Build the asset bundle.
-  AssetBundle assetBundle = new AssetBundle();
-  int result = await assetBundle.build(
+  final AssetBundle assetBundle = new AssetBundle();
+  final int result = await assetBundle.build(
     manifestPath: manifestPath,
     workingDirPath: workingDirPath,
     packagesPath: packagesPath,
@@ -213,7 +213,7 @@ Future<Null> assemble({
   if (result != 0)
     throwToolExit('Error building $outputPath: $result', exitCode: result);
 
-  ZipBuilder zipBuilder = new ZipBuilder();
+  final ZipBuilder zipBuilder = new ZipBuilder();
 
   // Add all entries from the asset bundle.
   zipBuilder.entries.addAll(assetBundle.entries);

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

@@ -97,18 +97,18 @@ class IOSDevice extends Device {
     if (!doctor.iosWorkflow.hasIDeviceId)
       return <IOSDevice>[];
 
-    List<IOSDevice> devices = <IOSDevice>[];
+    final List<IOSDevice> devices = <IOSDevice>[];
     for (String id in _getAttachedDeviceIDs(mockIOS)) {
-      String name = IOSDevice._getDeviceInfo(id, 'DeviceName', mockIOS);
+      final String name = IOSDevice._getDeviceInfo(id, 'DeviceName', mockIOS);
       devices.add(new IOSDevice(id, name: name));
     }
     return devices;
   }
 
   static Iterable<String> _getAttachedDeviceIDs([IOSDevice mockIOS]) {
-    String listerPath = (mockIOS != null) ? mockIOS.listerPath : _checkForCommand('idevice_id');
+    final String listerPath = (mockIOS != null) ? mockIOS.listerPath : _checkForCommand('idevice_id');
     try {
-      String output = runSync(<String>[listerPath, '-l']);
+      final String output = runSync(<String>[listerPath, '-l']);
       return output.trim().split('\n').where((String s) => s != null && s.isNotEmpty);
     } catch (e) {
       return <String>[];
@@ -116,7 +116,7 @@ class IOSDevice extends Device {
   }
 
   static String _getDeviceInfo(String deviceID, String infoKey, [IOSDevice mockIOS]) {
-    String informerPath = (mockIOS != null)
+    final String informerPath = (mockIOS != null)
         ? mockIOS.informerPath
         : _checkForCommand('ideviceinfo');
     return runSync(<String>[informerPath, '-k', infoKey, '-u', deviceID]).trim();
@@ -142,7 +142,7 @@ class IOSDevice extends Device {
   @override
   bool isAppInstalled(ApplicationPackage app) {
     try {
-      String apps = runCheckedSync(<String>[installerPath, '--list-apps']);
+      final String apps = runCheckedSync(<String>[installerPath, '--list-apps']);
       if (new RegExp(app.id, multiLine: true).hasMatch(apps)) {
         return true;
       }
@@ -157,8 +157,8 @@ class IOSDevice extends Device {
 
   @override
   bool installApp(ApplicationPackage app) {
-    IOSApp iosApp = app;
-    Directory bundle = fs.directory(iosApp.deviceBundlePath);
+    final IOSApp iosApp = app;
+    final Directory bundle = fs.directory(iosApp.deviceBundlePath);
     if (!bundle.existsSync()) {
       printError("Could not find application bundle at ${bundle.path}; have you run 'flutter build ios'?");
       return false;
@@ -203,7 +203,7 @@ class IOSDevice extends Device {
       printTrace('Building ${app.name} for $id');
 
       // Step 1: Build the precompiled/DBC application if necessary.
-      XcodeBuildResult buildResult = await buildXcodeProject(app: app, mode: mode, target: mainPath, buildForDevice: true);
+      final XcodeBuildResult buildResult = await buildXcodeProject(app: app, mode: mode, target: mainPath, buildForDevice: true);
       if (!buildResult.success) {
         printError('Could not build the precompiled application for the device.');
         await diagnoseXcodeBuildFailure(buildResult);
@@ -216,15 +216,15 @@ class IOSDevice extends Device {
     }
 
     // Step 2: Check that the application exists at the specified path.
-    IOSApp iosApp = app;
-    Directory bundle = fs.directory(iosApp.deviceBundlePath);
+    final IOSApp iosApp = app;
+    final Directory bundle = fs.directory(iosApp.deviceBundlePath);
     if (!bundle.existsSync()) {
       printError('Could not find the built application bundle at ${bundle.path}.');
       return new LaunchResult.failed();
     }
 
     // Step 3: Attempt to install the application on the device.
-    List<String> launchArguments = <String>["--enable-dart-profiling"];
+    final List<String> launchArguments = <String>["--enable-dart-profiling"];
 
     if (debuggingOptions.startPaused)
       launchArguments.add("--start-paused");
@@ -240,7 +240,7 @@ class IOSDevice extends Device {
     if (platformArgs['trace-startup'] ?? false)
       launchArguments.add('--trace-startup');
 
-    List<String> launchCommand = <String>[
+    final List<String> launchCommand = <String>[
       '/usr/bin/env',
       'ios-deploy',
       '--id',
@@ -271,12 +271,12 @@ class IOSDevice extends Device {
 
       // TODO(danrubel): The Android device class does something similar to this code below.
       // The various Device subclasses should be refactored and common code moved into the superclass.
-      ProtocolDiscovery observatoryDiscovery = new ProtocolDiscovery.observatory(
+      final ProtocolDiscovery observatoryDiscovery = new ProtocolDiscovery.observatory(
         getLogReader(app: app), portForwarder: portForwarder, hostPort: debuggingOptions.observatoryPort);
-      ProtocolDiscovery diagnosticDiscovery = new ProtocolDiscovery.diagnosticService(
+      final ProtocolDiscovery diagnosticDiscovery = new ProtocolDiscovery.diagnosticService(
         getLogReader(app: app), portForwarder: portForwarder, hostPort: debuggingOptions.diagnosticPort);
 
-      Future<Uri> forwardObsUri = observatoryDiscovery.nextUri();
+      final Future<Uri> forwardObsUri = observatoryDiscovery.nextUri();
       Future<Uri> forwardDiagUri;
       if (debuggingOptions.buildMode == BuildMode.debug) {
         forwardDiagUri = diagnosticDiscovery.nextUri();
@@ -284,9 +284,9 @@ class IOSDevice extends Device {
         forwardDiagUri = new Future<Uri>.value(null);
       }
 
-      Future<int> launch = runCommandAndStreamOutput(launchCommand, trace: true);
+      final Future<int> launch = runCommandAndStreamOutput(launchCommand, trace: true);
 
-      List<Uri> uris = await launch.then<List<Uri>>((int result) async {
+      final List<Uri> uris = await launch.then<List<Uri>>((int result) async {
         installationResult = result;
 
         if (result != 0) {
@@ -392,7 +392,7 @@ class _IOSDeviceLogReader extends DeviceLogReader {
     //
     // iOS 9 format:  Runner[297] <Notice>:
     // iOS 10 format: Runner(libsystem_asl.dylib)[297] <Notice>:
-    String appName = app == null ? '' : app.name.replaceAll('.app', '');
+    final String appName = app == null ? '' : app.name.replaceAll('.app', '');
     _lineRegex = new RegExp(appName + r'(\(.*\))?\[[\d]+\] <[A-Za-z]+>: ');
   }
 
@@ -420,7 +420,7 @@ class _IOSDeviceLogReader extends DeviceLogReader {
   }
 
   void _onLine(String line) {
-    Match match = _lineRegex.firstMatch(line);
+    final Match match = _lineRegex.firstMatch(line);
 
     if (match != null) {
       // Only display the log line after the initial device and executable information.
@@ -451,14 +451,14 @@ class _IOSDevicePortForwarder extends DevicePortForwarder {
     }
 
     // Usage: iproxy LOCAL_TCP_PORT DEVICE_TCP_PORT UDID
-    Process process = await runCommand(<String>[
+    final Process process = await runCommand(<String>[
       device.iproxyPath,
       hostPort.toString(),
       devicePort.toString(),
       device.id,
     ]);
 
-    ForwardedPort forwardedPort = new ForwardedPort.withContext(hostPort,
+    final ForwardedPort forwardedPort = new ForwardedPort.withContext(hostPort,
         devicePort, process);
 
     printTrace("Forwarded port $forwardedPort");
@@ -477,7 +477,7 @@ class _IOSDevicePortForwarder extends DevicePortForwarder {
 
     printTrace("Unforwarding port $forwardedPort");
 
-    Process process = forwardedPort.context;
+    final Process process = forwardedPort.context;
 
     if (process != null) {
       processManager.killPid(process.pid);

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

@@ -46,7 +46,7 @@ class IOSWorkflow extends DoctorValidator implements Workflow {
     if (!hasIosDeploy)
       return false;
     try {
-      Version version = new Version.parse(iosDeployVersionText);
+      final Version version = new Version.parse(iosDeployVersionText);
       return version >= new Version.parse(iosDeployMinimumVersion);
     } on FormatException catch (_) {
       return false;
@@ -55,7 +55,7 @@ class IOSWorkflow extends DoctorValidator implements Workflow {
 
   @override
   Future<ValidationResult> validate() async {
-    List<ValidationMessage> messages = <ValidationMessage>[];
+    final List<ValidationMessage> messages = <ValidationMessage>[];
     ValidationType xcodeStatus = ValidationType.missing;
     ValidationType pythonStatus = ValidationType.missing;
     ValidationType brewStatus = ValidationType.missing;
@@ -143,7 +143,7 @@ class IOSWorkflow extends DoctorValidator implements Workflow {
       } else {
         // Check for compatibility between libimobiledevice and Xcode.
         // TODO(cbracken) remove this check once libimobiledevice > 1.2.0 is released.
-        ProcessResult result = (await runAsync(<String>['idevice_id', '-l'])).processResult;
+        final ProcessResult result = (await runAsync(<String>['idevice_id', '-l'])).processResult;
         if (result.exitCode == 0 && result.stdout.isNotEmpty && !exitsHappy(<String>['ideviceName'])) {
           brewStatus = ValidationType.partial;
           messages.add(new ValidationMessage.error(

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

@@ -42,7 +42,7 @@ class Xcode {
       } else {
         try {
           printTrace('xcrun clang');
-          ProcessResult result = processManager.runSync(<String>['/usr/bin/xcrun', 'clang']);
+          final ProcessResult result = processManager.runSync(<String>['/usr/bin/xcrun', 'clang']);
 
           if (result.stdout != null && result.stdout.contains('license'))
             _eulaSigned = false;
@@ -88,8 +88,8 @@ class Xcode {
     if (!xcodeVersionRegex.hasMatch(xcodeVersionText))
       return false;
 
-    String version = xcodeVersionRegex.firstMatch(xcodeVersionText).group(1);
-    List<String> components = version.split('.');
+    final String version = xcodeVersionRegex.firstMatch(xcodeVersionText).group(1);
+    final List<String> components = version.split('.');
 
     _xcodeMajorVersion = int.parse(components[0]);
     _xcodeMinorVersion = components.length == 1 ? 0 : int.parse(components[1]);
@@ -115,7 +115,7 @@ Future<XcodeBuildResult> buildXcodeProject({
   bool buildForDevice,
   bool codesign: true
 }) async {
-  String flutterProjectPath = fs.currentDirectory.path;
+  final String flutterProjectPath = fs.currentDirectory.path;
   updateXcodeGeneratedProperties(flutterProjectPath, mode, target);
 
   if (!_checkXcodeVersion())
@@ -126,7 +126,7 @@ Future<XcodeBuildResult> buildXcodeProject({
 
   await _addServicesToBundle(fs.directory(app.appDirectory));
 
-  List<String> commands = <String>[
+  final List<String> commands = <String>[
     '/usr/bin/env',
     'xcrun',
     'xcodebuild',
@@ -136,7 +136,7 @@ Future<XcodeBuildResult> buildXcodeProject({
     'ONLY_ACTIVE_ARCH=YES',
   ];
 
-  List<FileSystemEntity> contents = fs.directory(app.appDirectory).listSync();
+  final List<FileSystemEntity> contents = fs.directory(app.appDirectory).listSync();
   for (FileSystemEntity entity in contents) {
     if (fs.path.extension(entity.path) == '.xcworkspace') {
       commands.addAll(<String>[
@@ -164,7 +164,7 @@ Future<XcodeBuildResult> buildXcodeProject({
     );
   }
 
-  RunResult result = await runAsync(
+  final RunResult result = await runAsync(
     commands,
     workingDirectory: app.appDirectory,
     allowReentrantFlutter: true
@@ -192,8 +192,8 @@ Future<XcodeBuildResult> buildXcodeProject({
     );
   } else {
     // Look for 'clean build/Release-iphoneos/Runner.app'.
-    RegExp regexp = new RegExp(r' clean (\S*\.app)$', multiLine: true);
-    Match match = regexp.firstMatch(result.stdout);
+    final RegExp regexp = new RegExp(r' clean (\S*\.app)$', multiLine: true);
+    final Match match = regexp.firstMatch(result.stdout);
     String outputDir;
     if (match != null)
       outputDir = fs.path.join(app.appDirectory, match.group(1));
@@ -202,9 +202,9 @@ Future<XcodeBuildResult> buildXcodeProject({
 }
 
 Future<Null> diagnoseXcodeBuildFailure(XcodeBuildResult result) async {
-  File plistFile = fs.file('ios/Runner/Info.plist');
+  final File plistFile = fs.file('ios/Runner/Info.plist');
   if (plistFile.existsSync()) {
-    String plistContent = plistFile.readAsStringSync();
+    final String plistContent = plistFile.readAsStringSync();
     if (plistContent.contains('com.yourcompany')) {
       printError('');
       printError('It appears that your application still contains the default signing identifier.');
@@ -232,7 +232,7 @@ Future<Null> diagnoseXcodeBuildFailure(XcodeBuildResult result) async {
     assert(result.xcodeBuildExecution.appDirectory != null);
     if (result.xcodeBuildExecution.buildForPhysicalDevice &&
         result.xcodeBuildExecution.buildCommands.contains('build')) {
-      RunResult checkBuildSettings = await runAsync(
+      final RunResult checkBuildSettings = await runAsync(
         result.xcodeBuildExecution.buildCommands..add('-showBuildSettings'),
         workingDirectory: result.xcodeBuildExecution.appDirectory,
         allowReentrantFlutter: true
@@ -302,8 +302,8 @@ bool _checkXcodeVersion() {
   if (!platform.isMacOS)
     return false;
   try {
-    String version = runCheckedSync(<String>['xcodebuild', '-version']);
-    Match match = _xcodeVersionRegExp.firstMatch(version);
+    final String version = runCheckedSync(<String>['xcodebuild', '-version']);
+    final Match match = _xcodeVersionRegExp.firstMatch(version);
     if (int.parse(match[1]) < 7) {
       printError('Found "${match[0]}". $_xcodeRequirement');
       return false;
@@ -316,7 +316,7 @@ bool _checkXcodeVersion() {
 }
 
 Future<Null> _addServicesToBundle(Directory bundle) async {
-  List<Map<String, String>> services = <Map<String, String>>[];
+  final List<Map<String, String>> services = <Map<String, String>>[];
   printTrace("Trying to resolve native pub services.");
 
   // Step 1: Parse the service configuration yaml files present in the service
@@ -325,12 +325,12 @@ Future<Null> _addServicesToBundle(Directory bundle) async {
   printTrace("Found ${services.length} service definition(s).");
 
   // Step 2: Copy framework dylibs to the correct spot for xcodebuild to pick up.
-  Directory frameworksDirectory = fs.directory(fs.path.join(bundle.path, "Frameworks"));
+  final Directory frameworksDirectory = fs.directory(fs.path.join(bundle.path, "Frameworks"));
   await _copyServiceFrameworks(services, frameworksDirectory);
 
   // Step 3: Copy the service definitions manifest at the correct spot for
   //         xcodebuild to pick up.
-  File manifestFile = fs.file(fs.path.join(bundle.path, "ServiceDefinitions.json"));
+  final File manifestFile = fs.file(fs.path.join(bundle.path, "ServiceDefinitions.json"));
   _copyServiceDefinitionsManifest(services, manifestFile);
 }
 
@@ -338,8 +338,8 @@ Future<Null> _copyServiceFrameworks(List<Map<String, String>> services, Director
   printTrace("Copying service frameworks to '${fs.path.absolute(frameworksDirectory.path)}'.");
   frameworksDirectory.createSync(recursive: true);
   for (Map<String, String> service in services) {
-    String dylibPath = await getServiceFromUrl(service['ios-framework'], service['root'], service['name']);
-    File dylib = fs.file(dylibPath);
+    final String dylibPath = await getServiceFromUrl(service['ios-framework'], service['root'], service['name']);
+    final File dylib = fs.file(dylibPath);
     printTrace("Copying ${dylib.path} into bundle.");
     if (!dylib.existsSync()) {
       printError("The service dylib '${dylib.path}' does not exist.");
@@ -352,12 +352,12 @@ Future<Null> _copyServiceFrameworks(List<Map<String, String>> services, Director
 
 void _copyServiceDefinitionsManifest(List<Map<String, String>> services, File manifest) {
   printTrace("Creating service definitions manifest at '${manifest.path}'");
-  List<Map<String, String>> jsonServices = services.map((Map<String, String> service) => <String, String>{
+  final List<Map<String, String>> jsonServices = services.map((Map<String, String> service) => <String, String>{
     'name': service['name'],
     // Since we have already moved it to the Frameworks directory. Strip away
     // the directory and basenames.
     'framework': fs.path.basenameWithoutExtension(service['ios-framework'])
   }).toList();
-  Map<String, dynamic> json = <String, dynamic>{ 'services' : jsonServices };
+  final Map<String, dynamic> json = <String, dynamic>{ 'services' : jsonServices };
   manifest.writeAsStringSync(JSON.encode(json), mode: FileMode.WRITE, flush: true);
 }

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

@@ -19,10 +19,10 @@ String getValueFromFile(String plistFilePath, String key) {
   if (!fs.isFileSync(plistFilePath))
     return null;
 
-  String normalizedPlistPath = fs.path.withoutExtension(fs.path.absolute(plistFilePath));
+  final String normalizedPlistPath = fs.path.withoutExtension(fs.path.absolute(plistFilePath));
 
   try {
-    String value = runCheckedSync(<String>[
+    final String value = runCheckedSync(<String>[
       '/usr/bin/defaults', 'read', normalizedPlistPath, key
     ]);
     return value.isEmpty ? null : value;

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

@@ -13,11 +13,11 @@ final RegExp _settingExpr = new RegExp(r'(\w+)\s*=\s*(\S+)');
 final RegExp _varExpr = new RegExp(r'\$\((.*)\)');
 
 void updateXcodeGeneratedProperties(String projectPath, BuildMode mode, String target) {
-  StringBuffer localsBuffer = new StringBuffer();
+  final StringBuffer localsBuffer = new StringBuffer();
 
   localsBuffer.writeln('// This is a generated file; do not edit or check into version control.');
 
-  String flutterRoot = fs.path.normalize(Cache.flutterRoot);
+  final String flutterRoot = fs.path.normalize(Cache.flutterRoot);
   localsBuffer.writeln('FLUTTER_ROOT=$flutterRoot');
 
   // This holds because requiresProjectRoot is true for this command
@@ -34,27 +34,27 @@ void updateXcodeGeneratedProperties(String projectPath, BuildMode mode, String t
 
   localsBuffer.writeln('SYMROOT=\${SOURCE_ROOT}/../${getIosBuildDirectory()}');
 
-  String flutterFrameworkDir = fs.path.normalize(fs.path.dirname(artifacts.getArtifactPath(Artifact.flutterFramework, TargetPlatform.ios, mode)));
+  final String flutterFrameworkDir = fs.path.normalize(fs.path.dirname(artifacts.getArtifactPath(Artifact.flutterFramework, TargetPlatform.ios, mode)));
   localsBuffer.writeln('FLUTTER_FRAMEWORK_DIR=$flutterFrameworkDir');
 
   if (artifacts is LocalEngineArtifacts) {
-    LocalEngineArtifacts localEngineArtifacts = artifacts;
+    final LocalEngineArtifacts localEngineArtifacts = artifacts;
     localsBuffer.writeln('LOCAL_ENGINE=${localEngineArtifacts.engineOutPath}');
   }
 
-  File localsFile = fs.file(fs.path.join(projectPath, 'ios', 'Flutter', 'Generated.xcconfig'));
+  final File localsFile = fs.file(fs.path.join(projectPath, 'ios', 'Flutter', 'Generated.xcconfig'));
   localsFile.createSync(recursive: true);
   localsFile.writeAsStringSync(localsBuffer.toString());
 }
 
 Map<String, String> getXcodeBuildSettings(String xcodeProjPath, String target) {
-  String absProjPath = fs.path.absolute(xcodeProjPath);
-  String out = runCheckedSync(<String>[
+  final String absProjPath = fs.path.absolute(xcodeProjPath);
+  final String out = runCheckedSync(<String>[
     '/usr/bin/xcodebuild', '-project', absProjPath, '-target', target, '-showBuildSettings'
   ]);
-  Map<String, String> settings = <String, String>{};
+  final Map<String, String> settings = <String, String>{};
   for (String line in out.split('\n').where(_settingExpr.hasMatch)) {
-    Match match = _settingExpr.firstMatch(line);
+    final Match match = _settingExpr.firstMatch(line);
     settings[match[1]] = match[2];
   }
   return settings;
@@ -64,10 +64,10 @@ Map<String, String> getXcodeBuildSettings(String xcodeProjPath, String target) {
 /// Substitutes variables in [str] with their values from the specified Xcode
 /// project and target.
 String substituteXcodeVariables(String str, String xcodeProjPath, String target) {
-  Iterable<Match> matches = _varExpr.allMatches(str);
+  final Iterable<Match> matches = _varExpr.allMatches(str);
   if (matches.isEmpty)
     return str;
 
-  Map<String, String> settings = getXcodeBuildSettings(xcodeProjPath, target);
+  final Map<String, String> settings = getXcodeBuildSettings(xcodeProjPath, target);
   return str.replaceAllMapped(_varExpr, (Match m) => settings[m[1]] ?? m[0]);
 }

packages/flutter_tools/lib/src/protocol_discovery.dart

@@ -50,7 +50,7 @@ class ProtocolDiscovery {
   /// The [Future] returned by this function will complete when the next service
   /// Uri is found.
   Future<Uri> nextUri() async {
-    Uri deviceUri = await _completer.future.timeout(
+    final Uri deviceUri = await _completer.future.timeout(
       const Duration(seconds: 60), onTimeout: () {
         throwToolExit('Timeout while attempting to retrieve Uri for $_serviceName');
       }
@@ -58,7 +58,7 @@ class ProtocolDiscovery {
     printTrace('$_serviceName Uri on device: $deviceUri');
     Uri hostUri;
     if (portForwarder != null) {
-      int devicePort = deviceUri.port;
+      final int devicePort = deviceUri.port;
       hostPort ??= await findPreferredPort(defaultHostPort);
       hostPort = await portForwarder
           .forward(devicePort, hostPort: hostPort)
@@ -79,8 +79,8 @@ class ProtocolDiscovery {
 
   void _onLine(String line) {
     Uri uri;
-    String prefix = '$_serviceName listening on ';
-    int index = line.indexOf(prefix + 'http://');
+    final String prefix = '$_serviceName listening on ';
+    final int index = line.indexOf(prefix + 'http://');
     if (index >= 0) {
       try {
         uri = Uri.parse(line.substring(index + prefix.length));

packages/flutter_tools/lib/src/run_cold.dart

@@ -83,14 +83,14 @@ class ColdRunner extends ResidentRunner {
 
     if (package == null) {
       String message = 'No application found for ${device.platform}.';
-      String hint = getMissingPackageHintForPlatform(device.platform);
+      final String hint = getMissingPackageHintForPlatform(device.platform);
       if (hint != null)
         message += '\n$hint';
       printError(message);
       return 1;
     }
 
-    Stopwatch startTime = new Stopwatch()..start();
+    final Stopwatch startTime = new Stopwatch()..start();
 
     Map<String, dynamic> platformArgs;
     if (traceStartup != null)
@@ -98,7 +98,7 @@ class ColdRunner extends ResidentRunner {
 
     await startEchoingDeviceLog(package);
 
-    String modeName = getModeName(debuggingOptions.buildMode);
+    final String modeName = getModeName(debuggingOptions.buildMode);
     if (mainPath == null) {
       assert(prebuiltMode);
       printStatus('Launching ${package.displayName} on ${device.name} in $modeName mode...');

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

@@ -32,7 +32,7 @@ class CoverageCollector {
     assert(process != null);
     assert(port != null);
 
-    int pid = process.pid;
+    final int pid = process.pid;
     int exitCode;
     process.exitCode.then<Null>((int code) {
       exitCode = code;
@@ -68,12 +68,12 @@ class CoverageCollector {
     if (_globalHitmap == null)
       return null;
     if (formatter == null) {
-      coverage.Resolver resolver = new coverage.Resolver(packagesPath: PackageMap.globalPackagesPath);
-      String packagePath = fs.currentDirectory.path;
-      List<String> reportOn = <String>[fs.path.join(packagePath, 'lib')];
+      final coverage.Resolver resolver = new coverage.Resolver(packagesPath: PackageMap.globalPackagesPath);
+      final String packagePath = fs.currentDirectory.path;
+      final List<String> reportOn = <String>[fs.path.join(packagePath, 'lib')];
       formatter = new coverage.LcovFormatter(resolver, reportOn: reportOn, basePath: packagePath);
     }
-    String result = await formatter.format(_globalHitmap);
+    final String result = await formatter.format(_globalHitmap);
     _globalHitmap = null;
     return result;
   }