Flutter – Encountered a "StateError (Bad state: Cannot emit new states after calling close)" upon the attempt to log in with Google

I’m using the flutter_firebase_login example from the official GitHub repository of flutter_bloc. My goal is to store supplementary user data in the Firestore database after a successful Google login, specifically for first-time users, in addition to their email, displayName, and photoURL.

Specifically, I’m storing the following fields in the user collection.

• firstName
• lastName
• email
• title
• company
• location
• bio
• interests
• profilePicture

With that said, the exception I encountered originated from the following code snippet, but despite that, I was still able to reach the home screen.

Future<void> logInWithGoogle() async {
  emit(state.copyWith(status : FormzSubmissionStatus.inProgress));
  try {
    await _authenticationRepository.logInWithGoogle();
    
    // NOTE: I added `createUserEntry` on top of the existing code 
    await _authenticationRepository.createUserEntry();

    emit(state.copyWith(status : FormzSubmissionStatus.success));
  }
  on LogInWithGoogleFailure catch (e) {
    emit(state.copyWith(errorMessage
                        : e.message, status
                        : FormzSubmissionStatus.failure, ), );
  }
  catch (_) {
    // NOTE: I got the exception here
    emit(state.copyWith(status : FormzSubmissionStatus.failure));
  }
}

I kept the rest of the code the same as in flutter_firebase_login; the only addition I made was introducing this method:

Future<void> createUserEntry() async {
  final user = _firebaseAuth.currentUser;
  final CollectionReference usersCollection =
      FirebaseFirestore.instance.collection('user');

  final DocumentReference userDocRef = usersCollection.doc(user !.uid);
  final DocumentSnapshot userDoc = await userDocRef.get();

  if (userDoc.exists) {
    // User entry already exists, no need to create a new one.
    return;
  }

  final nameParts = user.displayName !.split(' ');
  await userDocRef.set({
    'firstName' : nameParts.first,
    'lastName' : nameParts.last,
    'email' : user.email,
    'title' : '',
    'company' : '',
    'location' : null,
    'bio' : '',
    'interests' : null,
    'profilePicture' : null,
  });
}

Then, I call the method inside logInWithGoogle() after await _authenticationRepository.logInWithGoogle();

Interestingly enough, without createUserEntry, it successfully emits FormzSubmissionStatus.success, but when included, it does not.

Here are the logs:

[log] Change { currentState: LoginState(FormzInput<String, EmailValidationError>.pure(value: , isValid: false, error: EmailValidationError.invalid), FormzInput<String, PasswordValidationError>.pure(value: , isValid: false, error: PasswordValidationError.invalid), FormzSubmissionStatus.initial, false, null), nextState: LoginState(FormzInput<String, EmailValidationError>.pure(value: , isValid: false, error: EmailValidationError.invalid), FormzInput<String, PasswordValidationError>.pure(value: , isValid: false, error: PasswordValidationError.invalid), FormzSubmissionStatus.inProgress, false, null) }
[log] AuthBloc Instance of ‘_AppUserChanged’
[log] Transition { currentState: AuthState(AuthStatus.unauthenticated, User(null, , null, null)), event: Instance of ‘_AppUserChanged’, nextState: AuthState(AuthStatus.authenticated, User([email protected], MyID, My Name, My Picture)) }
[log] Change { currentState: AuthState(AuthStatus.unauthenticated, User(null, , null, null)), nextState: AuthState(AuthStatus.authenticated, User([email protected], MyID, My Name, My Picture)) }
2
[log] LoginCubit Bad state: Cannot emit new states after calling close

Here is the UI code that corresponds to the state emitted by the LoginCubit:

class LoginForm extends StatelessWidget {
  const LoginForm({super.key});

  @override
  Widget build(BuildContext context) {
    return BlocListener<LoginCubit, LoginState>(
      listener: (context, state) {
        if (state.status.isFailure) {
          ScaffoldMessenger.of(context)
            ..hideCurrentSnackBar()
            ..showSnackBar(
              SnackBar(
                content: Text(state.errorMessage ?? 'Authentication 
                           Failure'),
              ),
            );
        }
      },
      child: Align(
        alignment: const Alignment(0, -1 / 3),
        child: SingleChildScrollView(
          child: Column(
            mainAxisSize: MainAxisSize.min,
            children: [
              SvgPicture.asset(
                'assets/images/welcome.svg',
                height: 200.h,
              ),
              SizedBox(height: spaceXL.h),
              _EmailInput(),
              SizedBox(height: spaceS.h),
              _PasswordInput(),
              SizedBox(height: spaceM.h),
              _LoginButton(),
              SizedBox(height: spaceM.h),
              const Text('Or'),
              SizedBox(height: spaceM.h),
              _GoogleLoginButton(),
              SizedBox(height: spaceS.h),
              _SignUpButton(),
            ],
          ),
        ),
      ),
    );
  }
}

class _GoogleLoginButton extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MyButton.secondary(
      key: const Key('loginForm_googleLogin_raisedButton'),
      label: 'SIGN IN WITH GOOGLE',
      icon: Image.asset(
        'assets/images/google_logo.png',
        height: 25.h,
        fit: BoxFit.cover,
      ),
      onPressed: () => context.read<LoginCubit>().logInWithGoogle(),
    );
  }
}

Here is the code with BlocProvider:

class LoginPage extends StatelessWidget {
  const LoginPage({super.key});

  static Page<void> page() => const MaterialPage<void>(child: LoginPage());

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Padding(
        padding: const EdgeInsets.all(spaceL),
        child: BlocProvider(
          create: (_) => 
                LoginCubit(context.read<AuthenticationRepository>()),
          child: const LoginForm(),
        ),
      ),
    );
  }
}

Could someone shed some light on what might be wrong with my code?