[NestJS] 유닛 테스트(Unit Testing) 간단한 사용방법 코드 정리

유닛테스트 테스트 구조

 

describe('UsersExistsNicknameUseCase', () => {
  let service: UsersExistsNicknameUseCase;
  beforeEach(async () => {
    const module: TestingModule = await Test.createTestingModule({
      providers: [
        UsersExistsNicknameUseCase,
        PrismaService,
        {
          provide: 'EXISTS_NICKNAME',
          useClass: UsersExistsNicknameRepository,
        },
      ],
    }).compile();
 
    service = module.get<UsersExistsNicknameUseCase>(
      UsersExistsNicknameUseCase,
    );
  });
 
  let dto: UsersExistsNicknameInputDto;
  describe('exists nickname', () => {
    it('failed should nickname check', async () => {
      dto = {
        nickname: 'a',
      };
 
      const {
        response: { nickname },
      } = await service.existsNickname(dto);
 
      expect(nickname).toStrictEqual(false);
    });
 
    it('success should nickname check', async () => {
      dto = {
        nickname: 'nickaaa',
      };
 
      const {
        response: { nickname },
      } = await service.existsNickname(dto);
 
      expect(nickname).toStrictEqual(true);
    });
  });
 
  it('should be defined', () => {
    expect(service).toBeDefined();
  });
});