# How to Add Integration Tests Using Flutter Driver and the integration_test Package > Learn to add integration tests in Flutter using Flutter Driver and the integration_test package. Write and execute tests efficiently with our guide. - Repository: [Flutter/skills](https://github.com/flutter/skills) - Tags: how-to-guide - Published: 2026-05-09 --- **To add integration tests in Flutter, enable the Flutter Driver extension in a dedicated entry point, write tests using the `integration_test` package's `WidgetTester` API, and execute them with the `flutter drive` command.** Adding integration tests to your Flutter app ensures complete user flows work correctly across devices. According to the `flutter/skills` repository—specifically the `flutter-add-integration-test` skill documented in [`SKILL.md`](https://github.com/flutter/skills/blob/main/SKILL.md)—you combine the modern `integration_test` package with the optional Flutter Driver extension to create robust end-to-end tests. This workflow leverages `WidgetTester` for assertions while maintaining compatibility with external automation tools and MCP servers. ## Project Setup and Dependencies Start by declaring the required development dependencies in your [`pubspec.yaml`](https://github.com/flutter/skills/blob/main/pubspec.yaml). You need both `integration_test` and `flutter_test` from the Flutter SDK. ```yaml # pubspec.yaml dev_dependencies: integration_test: sdk: flutter flutter_test: sdk: flutter ``` These packages provide the `IntegrationTestWidgetsFlutterBinding` and the `WidgetTester` API necessary for driving the app UI and making assertions. ## Enable the Flutter Driver Extension Create a separate entry point file—conventionally `lib/main_test.dart`—that enables the driver extension before running your app. This step is required only if you need to support legacy `flutter_driver` workflows or MCP-driven interactive exploration. ```dart // lib/main_test.dart import 'package:flutter/material.dart'; import 'package:flutter_driver/driver_extension.dart'; import 'package:my_app/main.dart'; void main() { // Allows MCP / flutter_driver to control the app remotely enableFlutterDriverExtension(); runApp(const MyApp()); } ``` The `enableFlutterDriverExtension()` function registers a service extension that permits external tools to query the widget tree and inject input events. ## Author Integration Tests with the integration_test Package Place your test files in the `integration_test/` directory. Each test must initialize the binding and use `WidgetTester` to interact with widgets. ```dart // integration_test/app_test.dart import 'package:flutter_test/flutter_test.dart'; import 'package:integration_test/integration_test.dart'; import 'package:my_app/main.dart'; void main() { IntegrationTestWidgetsFlutterBinding.ensureInitialized(); group('End-to-end test', () { testWidgets('tap FAB and verify counter', (WidgetTester tester) async { await tester.pumpWidget(const MyApp()); // Verify counter starts at 0 expect(find.text('0'), findsOneWidget); // Tap the button with ValueKey('increment') await tester.tap(find.byKey(const ValueKey('increment'))); // Wait for animations to complete await tester.pumpAndSettle(); // Verify counter incremented to 1 expect(find.text('1'), findsOneWidget); }); }); } ``` The `IntegrationTestWidgetsFlutterBinding.ensureInitialized()` call bootstraps the test harness, while `pumpAndSettle()` ensures all frames and animations complete before assertions run. ## Create the Host Driver Script The `flutter drive` command requires a host driver script located in `test_driver/`. This minimal script acts as a bridge between the command-line tool and your integration test file. ```dart // test_driver/integration_test.dart import 'package:integration_test/integration_test_driver.dart'; Future main() => integrationDriver(); ``` The `integrationDriver()` function handles the communication protocol, forwards test results, and optionally collects performance timelines if profiling is enabled. ## Run Tests with flutter drive Execute your tests using the `flutter drive` command, specifying both the driver script and the target test file. ```bash flutter drive \ --driver=test_driver/integration_test.dart \ --target=integration_test/app_test.dart ``` For web testing, first start `chromedriver` on port 4444, then specify the device: ```bash chromedriver --port=4444 flutter drive \ --driver=test_driver/integration_test.dart \ --target=integration_test/app_test.dart \ -d chrome ``` This command compiles the app, launches it on the target device, executes the test logic, and reports results to the console. ## Interactive Exploration via MCP Before writing static tests, you can explore the app interactively using an MCP server that leverages the Flutter Driver extension. With the app running via `lib/main_test.dart`, the MCP tools can `launch_app`, `get_widget_tree`, `tap`, `enter_text`, and `scroll` to discover stable `ValueKey` identifiers. This exploration phase helps you identify the exact widget keys and navigation patterns to harden in your `integration_test/app_test.dart` file. ## Summary - Add `integration_test` and `flutter_test` to `dev_dependencies` in [`pubspec.yaml`](https://github.com/flutter/skills/blob/main/pubspec.yaml) - Enable the driver extension by calling `enableFlutterDriverExtension()` in `lib/main_test.dart` when legacy or MCP support is needed - Author tests in `integration_test/app_test.dart` using `IntegrationTestWidgetsFlutterBinding.ensureInitialized()` and the `WidgetTester` API - Provide a host driver script at `test_driver/integration_test.dart` that delegates to `integrationDriver()` - Execute the full suite with `flutter drive --driver=test_driver/integration_test.dart --target=integration_test/app_test.dart` ## Frequently Asked Questions ### What is the difference between the integration_test package and Flutter Driver? The **`integration_test`** package provides the modern, widget-level testing API using `WidgetTester` and is the recommended approach for new projects. **Flutter Driver** is the legacy remote-control API that remains useful for interactive MCP sessions or maintaining older test suites. According to the `flutter/skills` source code, you only need the driver extension if you require external tooling or legacy compatibility. ### Why do I need both a test file and a driver script? The file in `integration_test/` contains the actual test logic, assertions, and widget interactions. The driver script in `test_driver/integration_test.dart` acts as a minimal host required by the `flutter drive` command to initialize the test environment and report results. The `integrationDriver()` function in the host script forwards commands between the CLI and the app. ### Can I run integration tests on web or desktop targets? Yes. Use the `-d` flag with `flutter drive` to specify a device ID (for example, `-d chrome` for web). For web testing, you must first start `chromedriver` on port 4444. The same `integration_test` API works across Android, iOS, web, and desktop targets without code changes. ### Do I need to use the Flutter Driver extension for new projects? No. For standard end-to-end tests using only the `integration_test` package and `WidgetTester`, you do not need to call `enableFlutterDriverExtension()` or create a separate `main_test.dart` entry point. The extension is primarily required for MCP-driven interactive exploration or when migrating legacy `flutter_driver` tests that rely on the remote-control protocol.