Stabilize web integration tests for DWDS Promise collected flake

Author: rishika0212

packages/devtools_app_shared/lib/src/service/rpc_error_extension.dart

@@ -5,6 +5,13 @@
 import 'package:vm_service/vm_service.dart';
 
 extension RpcErrorExtension on RPCError {
+  /// Whether this [RPCError] represents a transient DWDS/CDP failure where a
+  /// JS promise was garbage collected before completion.
+  bool get isDwdsPromiseCollectedError {
+    return message.contains('Promise was collected') ||
+        toString().contains('Promise was collected');
+  }
+
   /// Whether this [RPCError] is some kind of "VM Service connection has gone"
   /// error that may occur if the VM is shut down.
   bool get isServiceDisposedError {

packages/devtools_app_shared/lib/src/service/service_extension_manager.dart

@@ -19,6 +19,7 @@ import 'service_extensions.dart' as extensions;
 import 'service_utils.dart';
 
 final _log = Logger('service_extension_manager');
+const _dwdsTransientRetryDelay = Duration(milliseconds: 100);
 
 /// Manager that handles tracking the service extension for the main isolate.
 final class ServiceExtensionManager with DisposerMixin {
@@ -59,6 +60,40 @@ final class ServiceExtensionManager with DisposerMixin {
   ConnectedApp get connectedApp => _connectedApp!;
   ConnectedApp? _connectedApp;
 
+  bool _shouldRetryServiceExtensionCall(Object error) {
+    return connectedApp.isDebuggableWebApp &&
+        error is RPCError &&
+        error.isDwdsPromiseCollectedError;
+  }
+
+  Future<Response> _callServiceExtensionWithRetry(
+    String method, {
+    String? isolateId,
+    Map<String, Object?>? args,
+  }) async {
+    try {
+      return await _service!.callServiceExtension(
+        method,
+        isolateId: isolateId,
+        args: args,
+      );
+    } catch (error, st) {
+      if (!_shouldRetryServiceExtensionCall(error)) rethrow;
+
+      _log.info(
+        'Retrying transient DWDS error for service extension $method: $error',
+        error,
+        st,
+      );
+      await Future<void>.delayed(_dwdsTransientRetryDelay);
+      return await _service!.callServiceExtension(
+        method,
+        isolateId: isolateId,
+        args: args,
+      );
+    }
+  }
+
   Future<void> _handleIsolateEvent(Event event) async {
     if (event.kind == EventKind.kServiceExtensionAdded) {
       // On hot restart, service extensions are added from here.
@@ -207,7 +242,7 @@ final class ServiceExtensionManager with DisposerMixin {
     _checkForFirstFrameStarted = true;
 
     try {
-      final value = await _service!.callServiceExtension(
+      final value = await _callServiceExtensionWithRetry(
         extensions.didSendFirstFrameEvent,
         isolateId: lastMainIsolate.id,
       );
@@ -317,7 +352,7 @@ final class ServiceExtensionManager with DisposerMixin {
       // The restore request is obsolete if the isolate has changed.
       if (isolateRef != _mainIsolate) return false;
       try {
-        final response = await _service!.callServiceExtension(
+        final response = await _callServiceExtensionWithRetry(
           name,
           isolateId: isolateRef.id,
         );
@@ -403,7 +438,7 @@ final class ServiceExtensionManager with DisposerMixin {
       try {
         if (value is bool) {
           Future<void> call(String? isolateId, bool value) async {
-            await _service!.callServiceExtension(
+            await _callServiceExtensionWithRetry(
               name,
               isolateId: isolateId,
               args: {'enabled': value},
@@ -423,13 +458,13 @@ final class ServiceExtensionManager with DisposerMixin {
             await call(mainIsolate.id, value);
           }
         } else if (value is String) {
-          await _service!.callServiceExtension(
+          await _callServiceExtensionWithRetry(
             name,
             isolateId: mainIsolate.id,
             args: {'value': value},
           );
         } else if (value is double) {
-          await _service!.callServiceExtension(
+          await _callServiceExtensionWithRetry(
             name,
             isolateId: mainIsolate.id,
             // The param name for a numeric service extension will be the last part

packages/devtools_app_shared/test/service/rpc_error_extension_test.dart

@@ -0,0 +1,29 @@
+// Copyright 2026 The Flutter Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file or at https://developers.google.com/open-source/licenses/bsd.
+
+import 'package:devtools_app_shared/src/service/rpc_error_extension.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:vm_service/vm_service.dart';
+
+void main() {
+  group('RpcErrorExtension', () {
+    test('detects DWDS promise collected errors', () {
+      final error = RPCError(
+        'Unexpected DWDS error: WipError -32000 Promise was collected',
+        RPCErrorKind.kServerError.code,
+      );
+
+      expect(error.isDwdsPromiseCollectedError, isTrue);
+    });
+
+    test('does not classify non-DWDS server errors as promise collected', () {
+      final error = RPCError(
+        'The client is closed',
+        RPCErrorKind.kServerError.code,
+      );
+
+      expect(error.isDwdsPromiseCollectedError, isFalse);
+    });
+  });
+}

packages/devtools_shared/lib/src/test/integration_test_runner.dart

@@ -49,7 +49,7 @@ class IntegrationTestRunner with IOMixin {
         '--driver=$testDriver',
         '--target=$testTarget',
         '-d',
-        headless ? 'web-server' : 'chrome',
+        'chrome',
         // --disable-gpu speeds up tests that use ChromeDriver when run on
         // GitHub Actions. See https://github.com/flutter/devtools/issues/8301.
         // However, it also breaks the tests when running with the wasm flag,
@@ -223,8 +223,7 @@ class IntegrationTestRunnerArgs {
   /// The path to the test target.
   String? get testTarget => argResults.option(testTargetArg);
 
-  /// Whether this integration test should be run on the 'web-server' device
-  /// instead of 'chrome'.
+  /// Whether this integration test should be run in headless Chrome.
   bool get headless => argResults.flag(_headlessArg);
 
   /// Whether this integration test should be run against dart2wasm-compiled DevTools.
@@ -280,10 +279,9 @@ class IntegrationTestRunnerArgs {
       ..addFlag(
         _headlessArg,
         negatable: false,
-        help:
-            'Runs the integration test on the \'web-server\' device instead of '
-            'the \'chrome\' device. For headless test runs, you will not be '
-            'able to see the integration test run visually in a Chrome browser.',
+        help: 'Runs the integration test on the \'chrome\' device in headless '
+            'mode. For headless test runs, you will not be able to see the '
+            'integration test run visually in a Chrome browser.',
       )
       ..addFlag(
         _wasmArg,