title: How to use Freezed package with Bloc in flutter?
body: <p>I want to create a simple bloc with freezed package. This is my bloc:</p>
  <pre><code>import 'package:bloc/bloc.dart';
  import 'package:freezed_annotation/freezed_annotation.dart';
  import 'package:presentation/presentation_index.dart';
  
  part 'auth_bloc_event.dart';
  part 'auth_bloc_state.dart';
  
  class AuthBlocBloc extends Bloc&lt;AuthEvent, AuthState&gt; {
    final SignUpBuyerUseCase signUpBuyerUseCase;
  
    AuthBlocBloc(this.signUpBuyerUseCase) : super(AuthState.initial());
  
    @override
    Stream&lt;AuthState&gt; mapEventToState(
      AuthEvent event,
    ) async* {
      yield* event.map();
      
    }
  }
  </code></pre>
  <p>and my event class :</p>
  <pre><code>part of 'auth_bloc.dart';
  
  @freezed
  abstract class AuthEvent with _$AuthEvent {
    const factory AuthEvent.login(String username, String password) = Login;
    const factory AuthEvent.signUpBuyer(BuyerEntity entity) = SignUpBuyer;
  }
  </code></pre>
  <p>and state class :</p>
  <pre><code>part of 'auth_bloc.dart';
  
  @freezed
  abstract class AuthState with _$AuthState {
    const factory AuthState.initial() = InitialAuthState;
    const factory AuthState.signUpBuyerFail(String error) = SignUpBuyerFail;
    const factory AuthState.signUpBuyerSuccess() = SignUpBuyerSuccess;
    const factory AuthState.signUpBuyerLoading() = SignUpBuyerLoading;
  }
  </code></pre>
  <p>The problem is that when i try to run</p>
  <blockquote>
  <p>flutter pub run build_runner watch --deleteonflicting-outputs</p>
  </blockquote>
  <p>Nothing happens and no classes are generated</p>