我有这个NestJS服务方法，我需要测试。

async getAllTests(orgId: string): Promise<Array<TestEntity>> {
  try {
    const query = this.repo.createQueryBuilder(this.tableName);
    query.where({ organization: orgId });
    const tests = await query.getMany();
    return tests;
  } catch (ex) {
    throw new InternalServerErrorException();
  }
}

字符串
我在我的测试文件中有这个，它并没有真正工作，但我认为它至少显示了我试图去的方向。

let service: TestService;
let repo: Repository<TestEntity>;

beforeEach(async () => {
  const module: TestingModule = await Test.createTestingModule({
    providers: [
      TestService,
      {
        provide: getRepositoryToken(TestEntity),
        useValue: {
          create: jest.fn(),
          save: jest.fn(),
          delete: jest.fn(),
          createQueryBuilder: jest.fn(() => ({
            where: jest.fn().mockReturnThis(),
            getMany: jest.fn(),
            getOne: jest.fn(),
          })),
        },
      },
    ],
  }).compile();

  service = module.get<TestService>(TestService);
  repo = module.get<Repository<TestEntity>>(getRepositoryToken(TestEntity));
});
  
describe('getAllTests()', () => {
  it('should successfully return a list of tests', async () => {
    const qb = repo.createQueryBuilder();
    jest.spyOn(qb, 'getMany').mockResolvedValue([]);

    const result = service.getAllTests('foo');
    await expect(result).resolves.toEqual([]);
  });

  it('should throw an error when createQueryBuilder() fails', async () => {
    jest.spyOn(repo, 'createQueryBuilder').mockImplementation(() => {
      throw new Error();
    });

    const result = () => service.getAllTests('foo');
    await expect(result).rejects.toThrow(InternalServerErrorException);
  });

  it('should throw an error when createQueryBuilder().where fails', async () => {
    jest.spyOn(repo.createQueryBuilder(), 'where').mockImplementation(() => {
      throw new Error();
    });

    const result = () => service.getAllTests('foo');
    await expect(result).rejects.toThrow(InternalServerErrorException);
  });

  it('should throw an error when createQueryBuilder().getMany fails', async () => {
    jest.spyOn(repo.createQueryBuilder(), 'getMany').mockImplementation(() => {
      throw new Error();
    });

    const result = () => service.getAllTests('foo');
    await expect(result).rejects.toThrow(InternalServerErrorException);
  });
});

型
如何模拟createQueryBuilder()及其方法的返回值或错误？现在，第一个应该实际返回数据的测试实际上返回了undefined，直接模拟createQueryBuilder()的测试可以工作，但其他测试报告如下：

Received promise resolved instead of rejected
Resolved to value: undefined

型