我需要测试一个在浏览器中打开一个新选项卡的功能

openStatementsReport(contactIds) {
  window.open(`a_url_${contactIds}`);
}

我想模拟窗口的打开函数,这样我就可以验证正确的URL被传递给打开函数。

使用笑话,我不知道如何模拟窗口。我试着设置窗口。使用mock函数打开,但这种方式不起作用。下面是测试用例:

it('the correct URL is called', () => {
  window.open = jest.fn();
  statementService.openStatementsReport(111);
  expect(window.open).toBeCalled();
});

但是它给出了误差

expect(jest.fn())[.not].toBeCalled()

jest.fn() value must be a mock function or spy.
    Received:
      function: [Function anonymous]

我应该对测试用例做什么?


当前回答

在我的组件,我需要访问window.location.search。这是我在Jest测试中所做的:

Object.defineProperty(global, "window", {
  value: {
    location: {
      search: "test"
    }
  }
});

如果窗口属性在不同的测试中必须不同,我们可以将窗口模拟放到函数中,并使其可写,以便在不同的测试中重写:

function mockWindow(search, pathname) {
  Object.defineProperty(global, "window", {
    value: {
      location: {
        search,
        pathname
      }
    },
    writable: true
  });
}

并在每次测试后重置:

afterEach(() => {
  delete global.window.location;
});

其他回答

我试过一个类似的测试,对我很有效……

我的代码:

export const Blah = () => {
        const BLAH = 'https://www.google.com/'
        const handleBlah = () => {
            window.open(BLAH, '_blank')
        }

    return (
        <button onClick={handleBlah}> BLAHBLAH </button>
    )
}

我的测试使用Jest:

it('should be able to render "BLAHBLAH " button ', () => {
    window.open = jest.fn();
    const BLAH = 'https://www.google.com/'
    const { getByText } = render(<Blah/>) // Get text by my page Blah
    const buttonGoToBlah = getByText('BLAHBLAH') // Get button by text
    fireEvent.click(buttonGoToBlah) // Simulate the click event

    expect(window.open).toHaveBeenCalledTimes(1) // Expect the window.open have to been called at least once.
    expect(window.open).toHaveBeenCalledWith(BLAH, '_blank'); // And the page should be the same called in my BLAH page
})

下面的方法对我很有效。这种方法允许我测试一些在浏览器和Node.js中都可以工作的代码,因为它允许我将window设置为undefined。

这是笑话24.8(我相信):

let windowSpy;

beforeEach(() => {
  windowSpy = jest.spyOn(window, "window", "get");
});

afterEach(() => {
  windowSpy.mockRestore();
});

it('should return https://example.com', () => {
  windowSpy.mockImplementation(() => ({
    location: {
      origin: "https://example.com"
    }
  }));

  expect(window.location.origin).toEqual("https://example.com");
});

it('should be undefined.', () => {
  windowSpy.mockImplementation(() => undefined);

  expect(window).toBeUndefined();
});

如果它类似于window.location.href中的窗口位置问题,则不能在测试中更改。#890,你可以尝试(调整):

delete global.window.open;
global.window = Object.create(window);
global.window.open = jest.fn();

在Jest配置中,添加setupFilesAfterEnv: ["./setupTests.js"],创建该文件,并添加您想要在测试之前运行的代码:

// setupTests.js
window.crypto = {
   .....
};

参考:setupFilesAfterEnv [array]

我们也可以在setupTests中使用global来定义它:

// File 'setupTests.js'
global.open = jest.fn()

并在实际测试中使用global调用它:

// File 'yourtest.test.js'
it('the correct URL is called', () => {
    statementService.openStatementsReport(111);
    expect(global.open).toBeCalled();
});