测试结果不是恒定的。开个玩笑，测试库

Question

当我做纱线测试时，结果不断变化。

这是错误名称 “请求失败，状态代码为 400”

但我已经Api的请求功能已经在模拟

像这样

import * as api from '@api/user';

jest.mock('@api/user');

(api.fetchApiKeyUpdate as jest.Mock).mockImplementationOnce(() => {
      throw { response: { data: { code: 'EX_INVALID_APIKEY_2015' } } };
});


(api.fetchApiKeyUpdate as jest.Mock).mockImplementationOnce(() => ({
      status: 'success',
      user: {
        id: '99b1231230',
        country: 'KR',
        language: 'ko',
      },
    }));

由此做出的测试通过。但是测试经常失败。我不知道我应该怀疑什么。

export const fetchApiKeyUpdate = async ({
  exchange,
  apiKey,
  secretKey,
  passphrase,
  otpCode,
}: ApiKeyUpdateRequest): Promise<UserInfoUpdateResponse | ApiAuthResponse> => {
  const { data } = await axios.post(
    apiKeyUpdateUrl,
    { apiKey, secretKey, passphrase, otpCode },
    { headers: { exchange } },
  );
  return data;
};

下面是我修改的部分代码

jest.mock('@api/user');

describe('API Register Success', () => {
  const mockResponse = {
    status: 'success',
    user: {
      id: '99bd10e123400',
      userName: 't123st07',
      receiveMarketingInfo: true,
    },
  };

  beforeEach(() => {
    (api.fetchApiKeyUpdate as jest.Mock).mockResolvedValueOnce(mockResponse);
  });

  it('키인증 성공시 아이콘 변경', async () => {
    const { container } = render(
      <ApiRegistrationBinanceTab
        isOpen
        handleOpenTab={jest.fn()}
      />,
    );

    userEvent.type(screen.getByPlaceholderText(/api key/i), 'apikey');
    userEvent.click(screen.getByRole('button', { name: /Verify/i }));

    await waitFor(() => {
      expect(container.querySelector('#certified-icon')).toBeTruthy();
    });
  });
});

describe('API Register Fail', () => {
  const mockResponse = { response: { data: { code: 'EX_INVALID_APIKEY_2015' } } };

  beforeEach(() => {
    (api.fetchApiKeyUpdate as jest.Mock).mockRejectedValueOnce(mockResponse);
  });

  it('remove input value if error code EX_INVALID_APIKEY_2015 or API_MANAGEMENT_ALREADY_REGISTERED', async () => {
    render(
      <ApiRegistrationBinanceTab
        isOpen
        handleOpenTab={jest.fn()}
      />,
    );

    userEvent.type(screen.getByPlaceholderText(/api key/i), 'apikey');
    userEvent.click(screen.getByRole('button', { name: /Verify/i }));

    await waitFor(() => {
      expect(screen.getByPlaceholderText(/api key/i)).toHaveValue('');
    });
  });
});

FAIL src/components/articles/modal/custom/forgotPassword/ForgotPassword.spec.tsx
  ● 비밀번호 변경 스텝별로 진행

    Request failed with status code 400

      at createError (node_modules/axios/lib/core/createError.js:16:15)
      at settle (node_modules/axios/lib/core/settle.js:17:12)
      at XMLHttpRequest.handleLoad (node_modules/axios/lib/adapters/xhr.js:62:7)
      at XMLHttpRequest.<anonymous> (node_modules/jsdom/lib/jsdom/living/helpers/create-event-accessor.js:32:32)
      at innerInvokeEventListeners ...

我申请 beforeEach 并更改 mockimplementationOnce > mockResolvedValueOnce，mockRejectedValueOnce

但问题是随着页面（测试）的更改，故障会间歇性出现。

我对错误消息感到好奇的是...我在请求中模拟了一个函数（如 fetchAuthMail.. fetchApiKeyUpdate）。

所以我不知道为什么错误消息来自 axios，即使我认为我实际上并没有在测试中提出请求。

Answer 1

您不应使用 mockImplementation，因为函数 return 是一个 Promise。只需使用 mockResolvedValue 和 mockRejectedValue 使其 return 成为 Promise。

此外，您应该将模拟与一些 describe 分开（每个用例一个）并将模拟添加到 beforeAll / beforeEach 函数中。

就我个人而言，我刚刚对其进行了测试，我保留了你的@api/user.ts（我刚刚添加了 axios 导入），并且通过使用这些文件它起作用了（100% 起作用，从未失败）：

index.ts

import * as api from '@api/user';

export const main = async () => {
  const response = await api.fetchApiKeyUpdate({
    exchange: 'fake-exchange',
    apiKey: 'fake-apiKey',
    secretKey: 'fake-secretKey',
    passphrase: 'fake-passphrase',
    otpCode: 'fake-otpCode',
  });
  return response.user;
};

index.spec.ts

import { main } from './index';

import * as api from '@api/user';
jest.mock('@api/user');

jest.mock('axios', () => ({
  post: jest.fn().mockImplementation(() => {
    console.error('axios should be mocked !'); // If some logs are shown, it means that one axios request was not mocked.
  }),
}));

describe('UT main tests', () => {
  describe('error', () => {
    beforeEach(() => {
      (api.fetchApiKeyUpdate as jest.Mock).mockRejectedValue({ response: { data: { code: 'EX_INVALID_APIKEY_2015' } } });
    });

    it('should rejects but not throw', async () => {
      // Note that if you want to use .toThrow() method, you should set in mockRejectedValue an Error
      await expect(main()).rejects.toStrictEqual({ response: { data: { code: 'EX_INVALID_APIKEY_2015' } } });
    });
  });

  describe('error thrown', () => {
    beforeEach(() => {
      (api.fetchApiKeyUpdate as jest.Mock).mockRejectedValue(Error('FAKE ERROR'));
    });

    it('should rejects and throw', async () => {
      // All working
      await expect(main()).rejects.toThrow(Error);
      await expect(main()).rejects.toThrowError('FAKE ERROR');
      await expect(main()).rejects.toThrowError(Error('FAKE ERROR'));
    });
  });


  describe('success', () => {
    const mockResponse = {
      status: 'success',
      user: {
        id: '99b1231230',
        country: 'KR',
        language: 'ko',
      },
    };

    beforeEach(() => {
      (api.fetchApiKeyUpdate as jest.Mock).mockResolvedValue(mockResponse);
    });

    it('should return user', async () => {
      const response = await main();
      expect(response).toStrictEqual(mockResponse.user);
    });
  });
});

编辑：我直接添加了一个 axios post 的模拟，你应该检查你的控制台上是否出现错误日志。如果是这样，则说明您忘记模拟一些 axios 调用。

测试结果不是恒定的。开个玩笑，测试库

The test results are not constant. in jest, testing-library

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