Testing Widgets

Let’s hope that here we can solve issues and ask questions about testing, E2E, widgets, and integration.

P.S.: My English isn’t very good :slight_smile:

Hi, so what is your question haha? :smiley:

1 Like

Looks like there is no question, but here is some tips using generative AI to write widget tests. Provide a widget test template content. Tell ChatGPT that you will give a widget and you want the widget tests according to this template strictly.

This is the widget test template:


/// This is a template for widget tests.
/// It is meant to be copied and pasted into a new file and then modified to fit the widget or feature you're testing

void main() {
  /// Name of the widget you're testing
  group('Widget tests group description', () {
    /// Registers a function to be run once before all tests.
    /// This is where you should register all fallback values for fakes
    setUpAll(() {});

    /// This is a setup method that will be called everytime before each test.
    /// Use it to initialize and register mocks.
    /// Avoid stubbing on top level, rather do it in the method group setup callback or test case itself.
    /// If you need test objects to be created, do it in the group or test case itself.
    ///
    /// only do generic setup here, if you need to do specific setup for a test case, do it in the test case
    setUp(() {
      /// Add dependency injection for a View modedel if needed for
      // DependencyInjection.bindMock((i) => testViewModel);.
    });

    /// This is a teardown method that will be called after each test
    /// use it to dispose of mocks and fakes if needed
    tearDown(() {});

    /// If widget functionality is very complex and might be divided to a smaller logical groups,
    /// test suite should be split to a smaller groups to ease understanding.
    /// Any setup that is specific to the subgroup and needs to be done once should be done in the subgroup's setup method
    /// otherwise in the test case itself
    group('subgroup-1', () {
      /// You can use the setup method to do stubbing for all test cases. If you need to do specific stubbing for a
      /// test case, do it in the test case itself.
      setUp(() {});

      /// Each test case should have a name that describes what it is testing and what the expected result is.
      /// Don't test too much in one case. If you need to test multiple things, create multiple test cases.
      /// Ideally, start the name with the word 'should' to make it clear what the expected result is and use the
      /// word 'when' to describe a specific scenario.

      testWidgets('should <expected result> when <action to perform>', (tester) async {
        /// Arrange
        /// Create test objects and stub methods here
        /// Set up needed data.
        await tester.pumpWidget(
          const WidgetTestApp(
            child: SizedBox.shrink(), // Insert your widget to test here.
          ),
        );
        await tester.pumpAndSettle();

        /// Act
        /// Call the method you're testing
        /// Perform Step 1.
        /// Perform Step 2.

        /// Assert
        /// Verify that the method did what it was supposed to do
        /// Assert that steps reached <expected result>
        expect('Actual result', 'Expected result', reason: 'Failure reason');
      });

      testWidgets('should <expected result 2> when <action to perform 2>', (tester) async {});
    });

    group('subgroup-2', () {
      setUp(() {});

      testWidgets('should <expected result 1> when <actions to perform 1>', (tester) async {});

      testWidgets('should <expected result 2> when <actions to perform 2>', (tester) async {});
    });
  });
}

similarly unit test template:


/// This is a template for unit tests. We use Flutter Mocktail package for unit tests.
/// It is meant to be copied and pasted into a new file and then modified to fit the class you're testing
void main() {
  /// Name of the class you're testing
  group(UnitTestTemplate, () {
    /// Registers a function to be run once before all tests.
    /// This is where you should register all fallback values for fakes
    setUpAll(() {});

    /// This is a setup method that will be called everytime before each test.
    /// Use it to initialize and register mocks.
    /// Avoid stubbing on top level, rather do it in the method group setup callback or test case itself.
    /// If you need test objects to be created, do it in the group or test case itself.
    ///
    /// only do generic setup here, if you need to do specific setup for a test case, do it in the test case
    setUp(() {});

    /// This is a teardown method that will be called after each test
    /// use it to dispose of mocks and fakes if needed
    tearDown(() {});

    /// Each instance method should have its own group with the name of the method
    /// Any setup that is specific to the method and needs to be done once should be done in the group's setup method
    /// otherwise in the test case itself
    group('method-1', () {
      /// You can use the setup method to do stubbing for all test cases. If you need to do specific stubbing for a
      /// test case, do it in the test case itself.
      setUp(() {});

      /// Each test case should have a name that describes what it is testing and what the expected result is.
      /// Don't test too much in one case. If you need to test multiple things, create multiple test cases.
      /// Ideally, start the name with the word 'should' to make it clear what the expected result is and use the
      /// word 'when' to describe a specific scenario.
      test('case 1', () {
        /// Arrange
        /// Create test objects and stub methods here

        /// Act
        /// Call the method you're testing

        /// Assert
        /// Verify that the method did what it was supposed to do
      });
      test('case 2', () {});
    });

    group('method-2', () {
      setUp(() {});

      test('case 1', () {});
      test('case 2', () {});
    });
  });
}

If you are interested in creating integration tests using Riverpod (to override services with mocks) and firebase_auth_mock (to override Firebase authentication), I built a sample app to help me understand how to do it (and to document a problem in the firebase_auth_mocks package):