javascript - Jest : Testing window. location.reload

Question

如何编写测试以确保方法 reloadFn 实际上重新加载窗口？我找到了 this resource但是我不清楚在给定函数中发生窗口重新加载时编写测试时如何期望窗口重新加载。感谢您的帮助!

const reloadFn = () => {
  window.location.reload(true);
}

Answer 1

更新答案(2021 年 11 月)

包装:“开 Jest ”:“^26.6.0”"@testing-library/jest-dom": "^5.11.4"

构建:create-react-app 4

describe("test window location's reload function", () => {
  const original = window.location;

  const reloadFn = () => {
    window.location.reload(true);
  };

  beforeAll(() => {
    Object.defineProperty(window, 'location', {
      configurable: true,
      value: { reload: jest.fn() },
    });
  });

  afterAll(() => {
    Object.defineProperty(window, 'location', { configurable: true, value: original });
  });

  it('mocks reload function', () => {
    expect(jest.isMockFunction(window.location.reload)).toBe(true);
  });

  it('calls reload function', () => {
    reloadFn(); // as defined above..
    expect(window.location.reload).toHaveBeenCalled();
  });
});

注意:更新了答案，因为 CRA 中使用的最新 jest 版本不支持 旧答案。

---

旧答案

这是解决方案，但为了更好的组织而重构:

describe('test window location\'s reload function', () => {
  const { reload } = window.location;

  beforeAll(() => {
    Object.defineProperty(window.location, 'reload', {
      configurable: true,
    });
    window.location.reload = jest.fn();
  });

  afterAll(() => {
    window.location.reload = reload;
  });

  it('mocks reload function', () => {
    expect(jest.isMockFunction(window.location.reload)).toBe(true);
  });

  it('calls reload function', () => {
    reloadFn(); // as defined above..
    expect(window.location.reload).toHaveBeenCalled();
  });
});

谢谢:)