[ Tool ] Ensure --dds-port=<port> is respected when targeting web devices (flutter#174278)

Fixes flutter#159157

Author: bkonyi

packages/flutter_tools/lib/src/isolated/devfs_web.dart

@@ -68,6 +68,7 @@ class WebDevFS implements DevFS {
     required this.buildInfo,
     required this.enableDwds,
     required this.enableDds,
+    this.ddsPort,
     required this.entrypoint,
     required this.expressionCompiler,
     required this.chromiumLauncher,
@@ -101,6 +102,7 @@ class WebDevFS implements DevFS {
   final BuildInfo buildInfo;
   final bool enableDwds;
   final bool enableDds;
+  final int? ddsPort;
   final bool testMode;
   final bool ddcModuleSystem;
   final bool canaryFeatures;
@@ -207,6 +209,7 @@ class WebDevFS implements DevFS {
       buildInfo,
       enableDwds,
       enableDds,
+      ddsPort,
       entrypoint,
       expressionCompiler,
       webRenderer: webRenderer,

packages/flutter_tools/lib/src/isolated/resident_web_runner.dart

@@ -297,6 +297,7 @@ class ResidentWebRunner extends ResidentRunner {
           buildInfo: debuggingOptions.buildInfo,
           enableDwds: supportsServiceProtocol,
           enableDds: debuggingOptions.enableDds,
+          ddsPort: debuggingOptions.ddsPort,
           entrypoint: _fileSystem.file(target).uri,
           expressionCompiler: expressionCompiler,
           chromiumLauncher: _chromiumLauncher,

packages/flutter_tools/lib/src/isolated/web_asset_server.dart

@@ -178,6 +178,7 @@ class WebAssetServer implements AssetReader {
     BuildInfo buildInfo,
     bool enableDwds,
     bool enableDds,
+    int? ddsPort,
     Uri entrypoint,
     ExpressionCompiler? expressionCompiler, {
     required WebDevServerConfig webDevServerConfig,
@@ -362,6 +363,7 @@ class WebAssetServer implements AssetReader {
           useSseForInjectedClient: useSseForInjectedClient,
           expressionCompiler: expressionCompiler,
           spawnDds: enableDds,
+          ddsPort: ddsPort,
         ),
         appMetadata: AppMetadata(hostname: hostname),
       ),

packages/flutter_tools/test/general.shard/web/devfs_web_ddc_modules_test.dart

@@ -1122,6 +1122,7 @@ void main() {
         ),
         false,
         false,
+        null,
         Uri.base,
         null,
         webRenderer: WebRendererMode.canvaskit,
@@ -1161,6 +1162,7 @@ void main() {
         ),
         false,
         false,
+        null,
         Uri.base,
         null,
         webRenderer: WebRendererMode.canvaskit,

packages/flutter_tools/test/general.shard/web/devfs_web_test.dart

@@ -1366,6 +1366,7 @@ void main() {
         ),
         false,
         false,
+        null,
         Uri.base,
         null,
         webRenderer: WebRendererMode.canvaskit,
@@ -1405,6 +1406,7 @@ void main() {
         ),
         false,
         false,
+        null,
         Uri.base,
         null,
         webRenderer: WebRendererMode.canvaskit,

packages/flutter_tools/test/integration.shard/test_driver.dart

@@ -537,6 +537,7 @@ final class FlutterRunTestDriver extends FlutterTestDriver {
     bool structuredErrors = false,
     bool noDevtools = false,
     bool verbose = false,
+    int? ddsPort,
     String? script,
     List<String>? additionalCommandArgs,
   }) async {
@@ -559,6 +560,7 @@ final class FlutterRunTestDriver extends FlutterTestDriver {
         if (device != GoogleChromeDevice.kChromeDeviceId) '--disable-service-auth-codes',
         '--machine',
         if (!spawnDdsInstance) '--no-dds',
+        if (ddsPort != null) '--dds-port=$ddsPort',
         if (noDevtools) '--no-devtools',
         ...getLocalEngineArguments(),
         '-d',

packages/flutter_tools/test/web.shard/vm_service_web_test.dart

@@ -9,6 +9,7 @@ import 'dart:async';
 
 import 'package:file/file.dart';
 import 'package:flutter_tools/src/base/file_system.dart';
+import 'package:flutter_tools/src/base/io.dart';
 import 'package:flutter_tools/src/vmservice.dart';
 import 'package:flutter_tools/src/web/web_device.dart';
 import 'package:vm_service/vm_service.dart';
@@ -24,18 +25,43 @@ void main() {
   final project = BasicProjectWithUnaryMain();
   late FlutterRunTestDriver flutter;
 
-  group('Clients of flutter run on web with DDS enabled', () {
-    setUp(() async {
-      tempDir = createResolvedTempDirectorySync('run_test.');
-      await project.setUpIn(tempDir);
-      flutter = FlutterRunTestDriver(tempDir);
-    });
+  setUp(() async {
+    tempDir = createResolvedTempDirectorySync('run_test.');
+    await project.setUpIn(tempDir);
+    flutter = FlutterRunTestDriver(tempDir);
+  });
 
-    tearDown(() async {
-      await flutter.stop();
-      tryToDelete(tempDir);
-    });
+  tearDown(() async {
+    await flutter.stop();
+    tryToDelete(tempDir);
+  });
 
+  testWithoutContext('flutter run on web respects --dds-port', () async {
+    // Regression test for https://github.com/flutter/flutter/issues/159157
+    Future<int> getFreePort() async {
+      final ServerSocket serverSocket = await ServerSocket.bind(InternetAddress.loopbackIPv4, 0);
+      try {
+        return serverSocket.port;
+      } finally {
+        await serverSocket.close();
+      }
+    }
+
+    final int ddsPort = await getFreePort();
+    await flutter.run(
+      withDebugger: true,
+      // Unfortunately, we can't easily test the web-server device as we'd need to attach to the
+      // server with a Chromedriver instance to initialize DWDS and start DDS. However, the DDS
+      // port is provided via the same code path to DWDS regardless of which device we use, so
+      // only testing against the Chrome device should be sufficient.
+      device: GoogleChromeDevice.kChromeDeviceId,
+      ddsPort: ddsPort,
+      additionalCommandArgs: <String>['--verbose', '--no-web-resources-cdn'],
+    );
+    expect(flutter.vmServicePort, ddsPort);
+  });
+
+  group('Clients of flutter run on web with DDS enabled', () {
     testWithoutContext('can validate flutter version', () async {
       await flutter.run(
         withDebugger: true,