Using Patrol finders in widget tests

Since patrol_finders is a separate package, referenced in patrol package, you can use it in your widget or golden tests, without depending on patrol. Below you can find a short tutorial on how to use $ in already existing widget tests.

Install#

First, add the patrol_finders package as a dev_dependency in your app's pubspec.yaml. You can do this by executing the following command in the app's directory:

flutter pub add patrol_finders --dev

Use#

Our custom finders depend only on Flutter itself. This means you can use them no matter if you're writing a mobile, web, desktop, or embedded app!

To use Patrol finders in your test files, first import it:

import 'package:patrol_finders/patrol_finders.dart';

Once imported, you can use it in widget tests:

test/widget_test_with_patrol_finders.dart

void main() {
  testWidgets(
    'counter is incremented when plus button is tapped',
    (WidgetTester tester) async {
      PatrolTester $ = PatrolTester(
        tester: tester,
        config: PatrolTesterConfig(),
      );
      await $.pumpWidget(const MyApp());

      expect($('0'), findsOneWidget);
      expect($('-1'), findsNothing);

      await $(Icons.remove).tap();

      expect($('0'), findsNothing);
      expect($('-1'), findsOneWidget);
    },
  );
}

Or you can use our wrapper on testWidgets method, which initializes PatrolTester object for you.

test/patrol_widget_test.dart

void main() {
  patrolWidgetTest(
    'counter is incremented when plus button is tapped',
    (PatrolTester $) async {
      await $.pumpWidget(const MyApp());

      expect($('0'), findsOneWidget);
      expect($('-1'), findsNothing);

      await $(Icons.remove).tap();

      expect($('0'), findsNothing);
      expect($('-1'), findsOneWidget);
    },
  );
}

To run the test, simply execute:

flutter test