用笑话测试 axios.create() 实例

Question

我从这个任务中尝试了很多解决方案。我想在没有任何库（jest-axios-mock、moaxios、msw 等）的情况下测试 axios 实例 api 调用。我希望这是可能的，因为我成功地测试了简单的 axios 调用（ axios.get / axios.post 没有 .create ）主要问题是我尝试测试 axios 实例调用，我在不同的尝试中遇到了三个主要错误。

1 axios_instance_1.axiosInstance 不是函数

2 无法读取未定义的属性 'then'

3 无法读取未定义的属性 'post'

当我尝试绕过模块 mock ( jestjs.io/docs/bypassing-module-mocks ) 时我得到了这个

我最后一次尝试是这样的

axios-instance.ts

import axios from "axios";
export const axiosInstance = axios.create({
    headers: {'X-Custom-Header': 'foobar'}
})

api.ts

import { axiosInstance } from "../instancec/axios-instance";
export const axiosInstanceCounter = () => {
  return axiosInstance({
    method: 'post'
  }).then((data) => {
    console.log(data)
  })
}

axios.test.ts

import { axiosInstanceCounter } from '../features/api/axiosTest';
import { axiosInstance } from '../features/instancec/axios-instance';
import axios, { AxiosResponse } from 'axios';

jest.mock('../features/instancec/axios-instance', () => ({
   const instance = {
     create: jest.fn(),
   };
   return jest.fn(() => instance);
}));

it('Axios instance standart test', async () => {
    (axiosInstance.post as jest.Mock).mockResolvedValueOnce(() =>
      Promise.resolve(),
    );
    await axiosInstanceCounter();
    expect(axiosInstance).toBeCalledTimes(1);
});

我收到的最后一个错误是无法读取未定义 的'post'。在文件夹 mocks 中创建模拟文件并从那里导出也无济于事。我不太明白为什么会这样，我将非常感谢任何提示，我也尝试了 jest.spyOn 选项，但失败了。

解决方案的补充

我用 ts-jest 替换了 mocked() 以避免警告

const mockedAxiosInstance = axiosInstance as jest.MockedFunction<
  typeof axiosInstance
>;

Answer 1

如你所见，return axiosInstance({意味着axiosInstance是一个函数，那么如果你想测试axiosInstanceCounter函数，只需将axiosInstance模拟为一个普通函数（在你的情况下，api 调用不会 return 任何东西）：

api.test.ts // 测试 api.ts

import { AxiosPromise } from "axios";
import { mocked } from "ts-jest/utils"; // a helper function from ts-jest
import { axiosInstanceCounter } from '../features/api/axiosTest'; // should be ../features/api ???
import { axiosInstance } from '../features/instancec/axios-instance';

jest.mock("../features/instancec/axios-instance");

describe("api", () => {
  describe("axiosInstanceCounter()", () => {
    it("should call api with correct parameters", async () => {
      // mock to resolve a Promise<void>
      mocked(axiosInstance).mockResolvedValue(Promise.resolve() as unknown as AxiosPromise<void>);

      await axiosInstanceCounter();

      expect(axiosInstance).toHaveBeenCalledWith({ method: "post" });
    });
  });
});

Answer 2

这也有效，而且对您的目的来说更简单

import { axiosInstanceCounter } from "../features/api/axiosTest";
import { axiosInstance } from "../features/instancec/axios-instance";

let apiSpy;
describe("getPokemonOptions", () => {
  beforeEach(() => {
    jest.clearAllMocks();
  });
  it("Axios instance standart test", async () => {
    apiSpy = jest.spyOn(axiosInstance, "post");
    apiSpy.mockResolvedValue({});
    await axiosInstanceCounter();
    expect(axiosInstance).toBeCalledTimes(1);
  });
});

用笑话测试 axios.create() 实例

Testing axios.create() instance with jest

javascript

typescript

reactjs

jestjs

axios