[web] enable prefer_final_locals lint (flutter#27420)

lib/web_ui/analysis_options.yaml

@@ -54,7 +54,6 @@ linter:
     prefer_const_literals_to_create_immutables: false
     prefer_contains: false
     prefer_equal_for_default_values: false
-    prefer_final_locals: false
     prefer_foreach: false
     prefer_generic_function_type_aliases: false
     prefer_initializing_formals: false

lib/web_ui/dev/browser.dart

@@ -102,10 +102,10 @@ abstract class Browser {
     // for the process to actually start. They should just wait for the HTTP
     // request instead.
     runZonedGuarded(() async {
-      Process process = await startBrowser();
+      final Process process = await startBrowser();
       _processCompleter.complete(process);
 
-      Uint8Buffer output = Uint8Buffer();
+      final Uint8Buffer output = Uint8Buffer();
       void drainOutput(Stream<List<int>> stream) {
         try {
           _ioSubscriptions
@@ -117,7 +117,7 @@ abstract class Browser {
       drainOutput(process.stdout);
       drainOutput(process.stderr);
 
-      int exitCode = await process.exitCode;
+      final int exitCode = await process.exitCode;
 
       // This hack dodges an otherwise intractable race condition. When the user
       // presses Control-C, the signal is sent to the browser and the test
@@ -134,7 +134,7 @@ abstract class Browser {
       }
 
       if (!_closed && exitCode != 0) {
-        String outputString = utf8.decode(output);
+        final String outputString = utf8.decode(output);
         String message = '$name failed with exit code $exitCode.';
         if (outputString.isNotEmpty) {
           message += '\nStandard output:\n$outputString';

lib/web_ui/dev/chrome.dart

@@ -59,8 +59,8 @@ class Chrome extends Browser {
   /// Starts a new instance of Chrome open to the given [url], which may be a
   /// [Uri] or a [String].
   factory Chrome(Uri url, {bool debug = false}) {
-    String version = ChromeArgParser.instance.version;
-    Completer<Uri> remoteDebuggerCompleter = Completer<Uri>.sync();
+    final String version = ChromeArgParser.instance.version;
+    final Completer<Uri> remoteDebuggerCompleter = Completer<Uri>.sync();
     return Chrome._(() async {
       final BrowserInstallation installation = await getOrInstallChrome(
         version,
@@ -80,7 +80,7 @@ class Chrome extends Browser {
       final bool isChromeNoSandbox =
           Platform.environment['CHROME_NO_SANDBOX'] == 'true';
       final String dir = environment.webUiDartToolDir.createTempSync('test_chrome_user_data_').resolveSymbolicLinksSync();
-      List<String> args = <String>[
+      final List<String> args = <String>[
         '--user-data-dir=$dir',
         url.toString(),
         if (!debug)

lib/web_ui/dev/edge.dart

@@ -59,11 +59,11 @@ class Edge extends Browser {
       // Debug is not a valid option for Edge. Remove it.
       String pathToOpen = url.toString();
       if(pathToOpen.contains('debug')) {
-        int index = pathToOpen.indexOf('debug');
+        final int index = pathToOpen.indexOf('debug');
         pathToOpen = pathToOpen.substring(0, index-1);
       }
 
-      Process process = await Process.start(
+      final Process process = await Process.start(
         installation.executable,
         <String>['$pathToOpen','-k'],
       );

lib/web_ui/dev/firefox.dart

@@ -56,7 +56,7 @@ class Firefox extends Browser {
   /// [Uri] or a [String].
   factory Firefox(Uri url, {bool debug = false}) {
     final String version = FirefoxArgParser.instance.version;
-    Completer<Uri> remoteDebuggerCompleter = Completer<Uri>.sync();
+    final Completer<Uri> remoteDebuggerCompleter = Completer<Uri>.sync();
     return Firefox._(() async {
       final BrowserInstallation installation = await getOrInstallFirefox(
         version,
@@ -83,8 +83,8 @@ user_pref("dom.max_script_run_time", 0);
 
       File(path.join(temporaryProfileDirectory.path, 'prefs.js'))
           .writeAsStringSync(_profile);
-      bool isMac = Platform.isMacOS;
-      List<String> args = <String>[
+      final bool isMac = Platform.isMacOS;
+      final List<String> args = <String>[
         url.toString(),
         '--profile',
         '${temporaryProfileDirectory.path}',

lib/web_ui/dev/firefox_installer.dart

@@ -26,7 +26,7 @@ class FirefoxArgParser extends BrowserArgParser {
   @override
   void populateOptions(ArgParser argParser) {
     final YamlMap browserLock = BrowserLock.instance.configuration;
-    String firefoxVersion = browserLock['firefox']['version'] as String;
+    final String firefoxVersion = browserLock['firefox']['version'] as String;
 
     argParser
       ..addOption(
@@ -196,7 +196,7 @@ class FirefoxInstaller {
 
     final io.File downloadedFile =
         io.File(path.join(versionDir.path, PlatformBinding.instance.getFirefoxDownloadFilename(version)));
-    io.IOSink sink = downloadedFile.openWrite();
+    final io.IOSink sink = downloadedFile.openWrite();
     await download.stream.pipe(sink);
     await sink.flush();
     await sink.close();
@@ -226,12 +226,12 @@ class FirefoxInstaller {
   /// Mounts the dmg file using hdiutil, copies content of the volume to
   /// target path and then unmounts dmg ready for deletion.
   Future<void> _mountDmgAndCopy(io.File dmgFile) async {
-    String volumeName = await _hdiUtilMount(dmgFile);
+    final String volumeName = await _hdiUtilMount(dmgFile);
 
     final String sourcePath = '$volumeName/Firefox.app';
     final String targetPath = path.dirname(dmgFile.path);
     try {
-      io.ProcessResult installResult = await io.Process.run('cp', <String>[
+      final io.ProcessResult installResult = await io.Process.run('cp', <String>[
         '-r',
         sourcePath,
         targetPath,
@@ -249,7 +249,7 @@ class FirefoxInstaller {
   }
 
   Future<String> _hdiUtilMount(io.File dmgFile) async {
-    io.ProcessResult mountResult = await io.Process.run('hdiutil', <String>[
+    final io.ProcessResult mountResult = await io.Process.run('hdiutil', <String>[
       'attach',
       '-readonly',
       '${dmgFile.path}',
@@ -260,7 +260,7 @@ class FirefoxInstaller {
               'Exit code ${mountResult.exitCode}.\n${mountResult.stderr}');
     }
 
-    List<String> processOutput = (mountResult.stdout as String).split('\n');
+    final List<String> processOutput = (mountResult.stdout as String).split('\n');
     final String? volumePath = _volumeFromMountResult(processOutput);
     if (volumePath == null) {
       throw BrowserInstallerException(
@@ -274,7 +274,7 @@ class FirefoxInstaller {
   // Output is of form: {devicename} /Volumes/{name}.
   String? _volumeFromMountResult(List<String> lines) {
     for (String line in lines) {
-      int pos = line.indexOf('/Volumes');
+      final int pos = line.indexOf('/Volumes');
       if (pos != -1) {
         return line.substring(pos);
       }
@@ -283,7 +283,7 @@ class FirefoxInstaller {
   }
 
   Future<void> _hdiUtilUnmount(String volumeName) async {
-    io.ProcessResult unmountResult = await io.Process.run('hdiutil', <String>[
+    final io.ProcessResult unmountResult = await io.Process.run('hdiutil', <String>[
       'unmount',
       '$volumeName',
     ]);
@@ -302,7 +302,7 @@ class FirefoxInstaller {
 Future<String> _findSystemFirefoxExecutable() async {
   final io.ProcessResult which =
       await io.Process.run('which', <String>['firefox']);
-  bool found = which.exitCode != 0;
+  final bool found = which.exitCode != 0;
   const String fireFoxDefaultInstallPath =
       '/Applications/Firefox.app/Contents/MacOS/firefox';
   if (!found) {

lib/web_ui/dev/licenses.dart

@@ -55,7 +55,7 @@ class LicensesCommand extends Command<bool> {
       RegExp(r'// Copyright 2013 The Flutter Authors\. All rights reserved\.');
 
   void _expectLicenseHeader(io.File file) {
-    List<String> head = file.readAsStringSync().split('\n').take(3).toList();
+    final List<String> head = file.readAsStringSync().split('\n').take(3).toList();
 
     _expect(head.length >= 3, 'File too short: ${file.path}');
     _expect(

lib/web_ui/dev/safari_ios.dart

@@ -61,7 +61,7 @@ class SafariIos extends Browser {
       // Uses `xcrun simctl`. It is a command line utility to control the
       // Simulator. For more details on interacting with the simulator:
       // https://developer.apple.com/library/archive/documentation/IDEs/Conceptual/iOS_Simulator_Guide/InteractingwiththeiOSSimulator/InteractingwiththeiOSSimulator.html
-      io.Process process = await io.Process.start('xcrun', <String>[
+      final io.Process process = await io.Process.start('xcrun', <String>[
         'simctl',
         'openurl', // Opens the url on Safari installed on the simulator.
         'booted', // The simulator is already booted.

lib/web_ui/dev/safari_macos.dart

@@ -64,7 +64,7 @@ class SafariMacOs extends Browser {
       // persistent state and wait until it opens.
       // The details copied from `man open` on macOS.
       // TODO(nurhan): https://github.com/flutter/flutter/issues/50809
-      Process process = await Process.start(installation.executable, <String>[
+      final Process process = await Process.start(installation.executable, <String>[
         // These are flags for `open` command line tool.
         '-F', // Open a fresh Safari with no persistent state.
         '-W', // Wait until the Safari opens.

lib/web_ui/dev/test_platform.dart

@@ -463,21 +463,21 @@ class OneOffHandler {
   ///
   /// [handler] will be unmounted as soon as it receives a request.
   String create(shelf.Handler handler) {
-    String path = _counter.toString();
+    final String path = _counter.toString();
     _handlers[path] = handler;
     _counter++;
     return path;
   }
 
   /// Dispatches [request] to the appropriate handler.
   FutureOr<shelf.Response> _onRequest(shelf.Request request) {
-    List<String> components = p.url.split(request.url.path);
+    final List<String> components = p.url.split(request.url.path);
     if (components.isEmpty) {
       return shelf.Response.notFound(null);
     }
 
-    String path = components.removeAt(0);
-    shelf.Handler? handler = _handlers.remove(path);
+    final String path = components.removeAt(0);
+    final shelf.Handler? handler = _handlers.remove(path);
     if (handler == null) {
       return shelf.Response.notFound(null);
     }
@@ -563,9 +563,9 @@ class BrowserManager {
     required PackageConfig packageConfig,
     bool debug = false,
   }) {
-    Browser browser = _newBrowser(url, browserEnvironment, debug: debug);
+    final Browser browser = _newBrowser(url, browserEnvironment, debug: debug);
 
-    Completer<BrowserManager> completer = Completer<BrowserManager>();
+    final Completer<BrowserManager> completer = Completer<BrowserManager>();
 
     // For the cases where we use a delegator such as `adb` (for Android) or
     // `xcrun` (for IOS), these delegator processes can shut down before the
@@ -658,7 +658,7 @@ class BrowserManager {
       'browser': _browserEnvironment.packageTestRuntime.identifier
     })));
 
-    int suiteID = _suiteID++;
+    final int suiteID = _suiteID++;
     RunnerSuiteController? controller;
     void closeIframe() {
       if (_closed) {
@@ -670,9 +670,9 @@ class BrowserManager {
 
     // The virtual channel will be closed when the suite is closed, in which
     // case we should unload the iframe.
-    VirtualChannel<dynamic> virtualChannel = _channel.virtualChannel();
-    int suiteChannelID = virtualChannel.id;
-    StreamChannel<dynamic> suiteChannel = virtualChannel.transformStream(
+    final VirtualChannel<dynamic> virtualChannel = _channel.virtualChannel();
+    final int suiteChannelID = virtualChannel.id;
+    final StreamChannel<dynamic> suiteChannel = virtualChannel.transformStream(
         StreamTransformer<dynamic, dynamic>.fromHandlers(handleDone: (EventSink<dynamic> sink) {
       closeIframe();
       sink.close();
@@ -697,7 +697,7 @@ class BrowserManager {
         final String mapPath = p.join(env.environment.webUiRootDir.path,
             'build', pathToTest, sourceMapFileName);
 
-        Map<String, Uri> packageMap = <String, Uri>{
+        final Map<String, Uri> packageMap = <String, Uri>{
           for (Package p in packageConfig.packages) p.name: p.packageUriRoot
         };
         final JSStackTraceMapper mapper = JSStackTraceMapper(

lib/web_ui/dev/test_runner.dart

@@ -590,7 +590,7 @@ class TestCommand extends Command<bool> with ArgUtils<bool> {
   ///
   /// Later the extra files will be deleted in [_cleanupExtraFilesUnderTestDir].
   Future<bool> _buildTest(TestBuildInput input) async {
-    String targetFileName = path.join(
+    final String targetFileName = path.join(
       environment.webUiBuildDir.path,
       '${input.path.relativeToWebUi}.browser_test.dart.js',
     );
@@ -603,7 +603,7 @@ class TestCommand extends Command<bool> with ArgUtils<bool> {
       directoryToTarget.createSync(recursive: true);
     }
 
-    List<String> arguments = <String>[
+    final List<String> arguments = <String>[
       '--no-minify',
       '--disable-inlining',
       '--enable-asserts',