I'm trying to run the command 'flutter packages pub run build_runner build' and I'm getting an error as return, can someone help me? - flutter-run

Question

I'm trying to run the command 'flutter packages pub run build_runner build' and I'm getting an error as return, can someone help me ??
This is my code
import 'package:chopper/chopper.dart';
part 'post_api_service.chopper.dart';
#ChopperApi(baseUrl: 'https://jsonplaceholder.typicode.com/posts')
abstract class PostApiService extends ChopperService {
#Get()
Future<Response> getPosts();
#Get(path: '/{id}')
Future<Response> getPost(#Path('id') int id);
#Post()
Future<Response> postPost(
#Body() Map<String, dynamic> body,
);
}
This is the return
PS C:\srs\innovation\chopper\chopper_api> flutter packages pub run build_runner build
[INFO] Generating build script...
[INFO] Generating build script completed, took 414ms
[WARNING] Invalidated precompiled build script due to missing asset graph.
[INFO] Precompiling build script......
[INFO] Precompiling build script... completed, took 1.1s
[SEVERE]
type 'Null' is not a subtype of type 'String' in type cast
pub finished with exit code 78
PS C:\srs\innovation\chopper\chopper_api>

Answer 1

Just run the below command:
flutter packages pub run build_runner build --delete-conflicting-outputs