LateInitializationError: Field 'iCategory' has not been initialized

August 23, 2023

I’m performing tests in flutter and this error is occurring (LateInitializationError: Field ‘iCategory’ has not been initialized.
test\interfaces\icategory_test.dart
iCategory
test\interfaces\icategory_test.dart:1
main.)

       //iterfaces/icategory.dart
        import '../models/categorias/category_model.dart';

        abstract class ICategory {
          Future<List<CategoryModel>> fetchCategory(int page);
        }

        //iterfaces/icategory_test.dart

        // ignore_for_file: avoid_print

        import 'package:flutter_test/flutter_test.dart';
        import 'package:app/interfaces/icategory.dart';

        late ICategory iCategory;
        void main() {
          test('Teste iCategory', () {
            print(iCategory);
          });
        }
        //Error - LateInitializationError: Field 'iCategory' has not been initialized.
        //test\interfaces\icategory_test.dart       iCategory
        //test\interfaces\icategory_test.dart:1
       //main.<fn>

>Solution :

You haven’t assign the value. First you need to create a class implementing ICategory.

class CategoryRepoImpl implements ICategory {
  @override
  Future<List<CategoryModel>> fetchCategory(int page) async {
    // your logic.....
    return [];// list of data
  }
}

void main() {
  late ICategory iCategory;
  setUp(() {
    iCategory = CategoryRepoImpl();
  });
  test('Teste iCategory', () {
    print(iCategory);
  });
}

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