Expect states in order in tests

[spoonsoftbl]

Is it possible to see all state changes in test ? Here example:

class ExampleController extends GetxController {

    final RxInt testInt = 0.obs;

    void exampleVoid() {
        testInt.value = 1;
        testInt.value = 2;
        testInt.value = 3;
        testInt.value = 4;
        testInt.value = 5;
    }

} 

test('''Example test''', () {
      expect(controller.testInt, 0);
      controller.exampleVoid();
      expect(controller.testInt, 1);
      expect(controller.testInt, 2);
      expect(controller.testInt, 3);
      expect(controller.testInt, 4);
      expect(controller.testInt, 5);
  });

Now we can check only last value in expect (here 5).

[jonataslaw]

I don't think so, if the state change happened in the same void, only the last one will be observed from the build, so it doesn't make sense to test the state of something that doesn't exist. Unless you make the operation asynchronous and await a pump to wait for the build to occur, after each state change.

[spoonsoftbl]

Here is a more real case where I need to set flag loadingViewVisible and test every possible scenario in unit test (with emailValidation error or error from usecase/backend). Show error event - show error snackbar on view class.

import 'package:email_validator/email_validator.dart';
import 'package:event/event.dart';
import 'package:get/get.dart';
import 'package:shared/common/utils/strings.dart';

import 'forget_password_event_args.dart';
import 'forget_password_use_case.dart';

class ForgetPasswordController extends GetxController {
  final Event<ForgetPasswordEventArgs> forgetPasswordEvent;
  final ForgetPasswordUseCase forgetPasswordUseCase;

  ForgetPasswordController(
      {required this.forgetPasswordEvent, required this.forgetPasswordUseCase});

  final RxBool loadingViewVisible = false.obs;

  Future<void> forgetPassword(String email) async {
    loadingViewVisible.value = true;
    if (_isValidEmail(email)) {
      try {
        await forgetPasswordUseCase.forgetPassword(email);
        forgetPasswordEvent.broadcast(ForgetPasswordEventArgs.showDialog());
      } catch (err) {
        forgetPasswordEvent
            .broadcast(ForgetPasswordEventArgs.showError(err.toString()));
        rethrow;
      } finally {
        loadingViewVisible.value = false;
      }
    } else {
      loadingViewVisible.value = false;
      forgetPasswordEvent
          .broadcast(ForgetPasswordEventArgs.showError(Strings.emailNotValid));
    }
  }

  //region Private methods
  bool _isValidEmail(String email) => EmailValidator.validate(email);
  //endregion
}

[spoonsoftbl]

In RxJava we have assertValues method: https://www.tabnine.com/code/java/methods/io.reactivex.observers.TestObserver/assertValues