flutter-add-integration-test

by flutter

Configures Flutter Driver for app interaction and converts MCP actions into permanent integration tests. Use when adding integration testing to a project,… npx skills add https://github.com/flutter/skills --skill flutter-add-integration-test Download ZIPGitHub2.6k

Implementing Flutter Integration Tests

Contents

• Project Setup and Dependencies

• Interactive Exploration via MCP

• Test Authoring Guidelines

• Execution and Profiling

• Workflow: End-to-End Integration Testing

• Examples

Interactive Exploration via MCP

Use the Dart/Flutter MCP server tools to interactively explore and manipulate the application state before writing static tests.

• Launch: Execute launch_app with target: "lib/main_test.dart" to start the application and acquire the DTD URI.

• Inspect: Execute get_widget_tree to discover available Keys, Text nodes, and widget Types.

• Interact: Execute tap, enter_text, and scroll to simulate user flows.

• Wait: Always execute waitFor or verify state with get_health when navigating or triggering animations.

• Troubleshoot Unmounted Widgets: If a widget is not found in the tree, it may be lazily loaded in a SliverList or ListView. Execute scroll or scrollIntoView to force the widget to mount before interacting with it.

Test Authoring Guidelines

Structure integration tests using the flutter_test API paradigm.

• Create a dedicated integration_test/ directory at the project root.

• Name all test files using the <name>_test.dart convention.

• Initialize the binding by calling IntegrationTestWidgetsFlutterBinding.ensureInitialized(); at the start of main().

• Load the application UI using await tester.pumpWidget(MyApp());.

• Trigger frames and wait for animations to complete using await tester.pumpAndSettle(); after interactions like tester.tap().

• Assert widget visibility using expect(find.byKey(ValueKey('foo')), findsOneWidget); or findsNothing.

• Scroll to specific off-screen widgets using await tester.scrollUntilVisible(itemFinder, 500.0, scrollable: listFinder);.

Conditional Logic for Legacy flutter_driver:

• If maintaining or migrating legacy flutter_driver tests, use driver.waitFor(), driver.waitForAbsent(), driver.tap(), and driver.scroll() instead of the WidgetTester APIs.

Execution and Profiling

Execute tests using the flutter drive command. Require a host driver script located in test_driver/integration_test.dart that calls integrationDriver().

Conditional Execution Targets:

• If testing on Chrome: Launch chromedriver --port=4444 in a separate terminal, then run: flutter drive --driver=test_driver/integration_test.dart --target=integration_test/app_test.dart -d chrome

• If testing headless web: Run with -d web-server.

• If testing on Android (Local): Run flutter drive --driver=test_driver/integration_test.dart --target=integration_test/app_test.dart.

• If testing on Firebase Test Lab (Android):

• Build debug APK: flutter build apk --debug

• Build test APK: ./gradlew app:assembleAndroidTest

• Upload both APKs to the Firebase Test Lab console.

Workflow: End-to-End Integration Testing

Copy and follow this checklist to implement and verify integration tests.

• Task Progress: Setup

• Add integration_test and flutter_test to pubspec.yaml.

• Inject enableFlutterDriverExtension() into the app entry point.

• Assign ValueKeys to target widgets.

• Task Progress: Exploration

• Run launch_app via MCP.

• Map the widget tree using get_widget_tree.

• Validate interaction paths using MCP tools (tap, enter_text).

• Task Progress: Authoring

• Create integration_test/app_test.dart.

• Write test cases using WidgetTester APIs.

• Create test_driver/integration_test.dart with integrationDriver().

• Task Progress: Execution & Feedback Loop

• Run flutter drive --driver=test_driver/integration_test.dart --target=integration_test/app_test.dart.

• Feedback Loop: Review test output -> If PumpAndSettleTimedOutException occurs, check for infinite animations -> If widget not found, add scrollUntilVisible -> Re-run test until passing.

Examples

Standard Integration Test (integration_test/app_test.dart)

import 'package:flutter/material.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 on the floating action button, verify counter', (tester) async {
 // Load app widget.
 await tester.pumpWidget(const MyApp());

 // Verify the counter starts at 0.
 expect(find.text('0'), findsOneWidget);

 // Find the floating action button to tap on.
 final fab = find.byKey(const ValueKey('increment'));

 // Emulate a tap on the floating action button.
 await tester.tap(fab);

 // Trigger a frame and wait for animations.
 await tester.pumpAndSettle();

 // Verify the counter increments by 1.
 expect(find.text('1'), findsOneWidget);
 });
 });
}

Host Driver Script (test_driver/integration_test.dart)

import 'package:integration_test/integration_test_driver.dart';

Future main() => integrationDriver();

Performance Profiling Driver Script (test_driver/perf_driver.dart)

Use this driver script if you wrap your test actions in binding.traceAction() to capture performance metrics.

import 'package:flutter_driver/flutter_driver.dart' as driver;
import 'package:integration_test/integration_test_driver.dart';

Future main() {
 return integrationDriver(
 responseDataCallback: (data) async {
 if (data != null) {
 final timeline = driver.Timeline.fromJson(
 data['scrolling_timeline'] as Map ,
 );

 final summary = driver.TimelineSummary.summarize(timeline);

 await summary.writeTimelineToFile(
 'scrolling_timeline',
 pretty: true,
 includeSummary: true,
 );
 }
 },
 );
}