group_test_case.dart

group('User inputs valid form values', () {
    const Duration delayedDuration = const Duration(milliseconds: 50);

    setUp(() {
      mockHttpClient = MockHttpClient();
      when(mockHttpClient.post<Map<String, dynamic>>(any,
              data: anyNamed('data')))
          .thenAnswer((_) async {
            await Future.delayed(delayedDuration);
            return Future<Response<Map<String, dynamic>>>.value(
                  Response<Map<String, dynamic>>(data: <String, dynamic>{
                'token': 'token',
                'user': UserFactory.constructDefaultUserJson()
              }));
          });
    });

    Future<void> chooseImageThenFillInAllFormThenScrollThenTapSubmitButton(WidgetTester tester) async {
      await chooseImageFromImagePicker(tester);
      await fillInAllFormWithValidInput(tester);
      await scrollUntilBottom(tester);

      final Finder submit = find.widgetWithText(InkWell, 'Register');
      await tester.tap(submit);
      await tester.pump();
    }

    testWidgets('Test submit status code 200 should redirect to another page',
        (WidgetTester tester) async {
      await tester.pumpWidget(makeTestableWidget(child: page));
      await chooseImageThenFillInAllFormThenScrollThenTapSubmitButton(tester);
      await tester.pumpAndSettle(delayedDuration);
      await tester.pumpAndSettle();
      expect(find.byType(DashboardPage), findsOneWidget);
    });
}