Question

我是新手，只是想为使用第三方节点模块的简单功能实现单元测试。

要测试的功能（假设它存在于utilFolder.js中）：

import moduleName from 'third_party_module'
const util = {
   simple_function() {
      const name = moduleName.func1();
   }
}

export default util;

测试文件：

import util from "utilFolder";
import moduleName  from 'third_party_module';
jest.mock("third_party_module", () => ({
   func1: jest.fn()
}));

describe("was mocked functions called", () {
  test("was mocked functions called??", () => {
      util.simple_function();
      expect(moduleName.func1).toHaveBeenCalled();
  });
});

错误： Expected mock function to have been called, but it was not called。

请帮忙吗？

Answer 1

使用jest.mock模拟模块。这是工作示例：

util.js：

import moduleName from './third_party_module';

const util = {
  simple_function() {
    const name = moduleName.func1();
  }
};

export default util;

third_party_module.js：

export default {
  func1() {}
};

util.spec.js：

import util from './util';
import moduleName from './third_party_module';

jest.mock('./third_party_module', () => ({
  func1: jest.fn()
}));

describe('was mocked functions called', () => {
  test('was mocked functions called??', () => {
    util.simple_function();
    expect(moduleName.func1).toHaveBeenCalled();
  });
});

单元测试结果：

 PASS  src/stackoverflow/54729837/util.spec.js (8.414s)
  was mocked functions called
    ✓ was mocked functions called?? (4ms)

Test Suites: 1 passed, 1 total
Tests:       1 passed, 1 total
Snapshots:   0 total
Time:        9.742s

源代码：https://github.com/mrdulin/jest-codelab/tree/master/src/stackoverflow/54729837

如何正确模拟节点模块以进行Jest单元测试

1 个答案: