How to mock window.location.href with Jest + Vuejs?

Currently, I am implementing unit test for my project and there is a file that contained window.location.href.

I want to mock this to test and here is my sample code:

it("method A should work correctly", () => {
      const url = "http://dummy.com";
      Object.defineProperty(window.location, "href", {
        value: url,
        writable: true
      });
      const data = {
        id: "123",
        name: null
      };
      window.location.href = url;
      wrapper.vm.methodA(data);
      expect(window.location.href).toEqual(url);
    });

But I get this error:

TypeError: Cannot redefine property: href
        at Function.defineProperty (<anonymous>)

I had tried some solutions but not resolve it. I need some hints to help me get out of this trouble. Plz help.

You can try:

global.window = Object.create(window);
const url = "http://dummy.com";
Object.defineProperty(window, 'location', {
  value: {
    href: url
  }
});
expect(window.location.href).toEqual(url);  

Have a look at the Jest Issue for that problem:
Jest Issue

2020 Update

---

Basic

The URL object has a lot of the same functionality as the Location object. In other words, it includes properties such as pathname, search, hostname, etc. So for most cases, you can do the following:

delete window.location
window.location = new URL('https://www.example.com')

Advanced

You can also mock Location methods that you might need, which don't exist on the URL interface:

const location = new URL('https://www.example.com')
location.assign = jest.fn()
location.replace = jest.fn()
location.reload = jest.fn()

delete window.location
window.location = location

I have resolved this issue by adding writable: true and move it to beforeEach

Here is my sample code:

global.window = Object.create(window);
const url = "http://dummy.com";
Object.defineProperty(window, "location", {
    value: {
       href: url
    },
    writable: true
});

Solution for 2019 from GitHub: > > delete global.window.location; > global.window = Object.create(window); > global.window.location = { > port: '123', > protocol: 'http:', > hostname: 'localhost', > };

The best is probably to create a new URL instance, so that it parses your string like location.href does, and so it updates all the properties of location like .hash, .search, .protocol etc.

it("method A should work correctly", () => {
  const url = "http://dummy.com/";
  Object.defineProperty(window, "location", {
    value: new URL(url)
  } );
  
  window.location.href = url;
  expect(window.location.href).toEqual(url);
  
  window.location.href += "#bar"
  expect(window.location.hash).toEqual("#bar");
});

https://repl.it/repls/VoluminousHauntingFunctions

Many of the examples provided doesn't mock the properties of the original Location object.

What I do is just replace Location object (window.location) by URL, because URL contains the same properties as Location object like "href", "search", "hash", "host".

Setters and Getters also work exactly like the Location object.

Example:

const realLocation = window.location;

describe('My test', () => {

    afterEach(() => {
        window.location = realLocation;
    });

    test('My test func', () => {

        // @ts-ignore
        delete window.location;

        // @ts-ignore
        window.location = new URL('http://google.com');

        console.log(window.location.href);

        // ...
    });
});

Working example with @testing-library/react in 2020 for window.location.assign:

  afterEach(cleanup)
  beforeEach(() => {
    Object.defineProperty(window, 'location', {
      writable: true,
      value: { assign: jest.fn() }
    })
  })

Extending @jabacchetta's solution to avoid this setting bleeding into other tests:

describe("Example", () => {
  let location;

  beforeEach(() => {
    const url = "https://example.com";
    location = window.location;
    const mockLocation = new URL(url);
    mockLocation.replace = jest.fn();
    delete window.location;
    window.location = mockLocation;
  });

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

You can try a helper:

const setURL = url => global.jsdom.reconfigure({url});

describe('Test current location', () => {
  test('with GET parameter', () => {
    setURL('https://test.com?foo=bar');
    // ...your test here
  });
});

JSDOM Version

Another method, using JSDOM, which will provide window.location.href and all of the other properties of window.location, (e.g. window.location.search to get query string parameters).

import { JSDOM } from 'jsdom';

...

const { window } = new JSDOM('', {
	url: 'https://localhost/?testParam=true'
});
delete global.window;
global.window = Object.create(window);

you can try jest-location-mock.

npm install --save-dev jest-location-mock

update jest configs at jest.config.js file or jest prop inside package.json:

setupFilesAfterEnv: [ "./config/jest-setup.js" ]

create jest-setup.js

import "jest-location-mock";

usage:

it("should call assign with a relative url", () => {
    window.location.assign("/relative-url");
    expect(window.location).not.toBeAt("/");
    expect(window.location).toBeAt("/relative-url");
});

Can rewrite window.location by delete this global in every test.

delete global.window.location;
const href = 'http://localhost:3000';
global.window.location = { href };

Based on examples above and in other threads, here is a concrete example using jest that might help someone:

describe('Location tests', () => {
    const originalLocation = window.location;

    const mockWindowLocation = (newLocation) => {
        delete window.location;
        window.location = newLocation;
    };

    const setLocation = (path) =>
        mockWindowLocation(
            new URL(`https://example.com${path}`)
        );

    afterEach(() => {
        // Restore window.location to not destroy other tests
        mockWindowLocation(originalLocation);
    });

    it('should mock window.location successfully', () => {
        setLocation('/private-path');

        expect(window.location.href).toEqual(
            `https://example.com/private-path`
        );
    });
});

This is valid for Jest + TypeScript + Next.js (in case you use useRoute().push

const oldWindowLocation = window.location;

beforeAll(() => {
  delete window.location;
  window.location = { ...oldWindowLocation, assign: jest.fn() };
});

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

Probably irrelevant. But for those seeking a solution for window.open('url', attribute) I applied this, with help of some comments above:

window = Object.create(window);
const url = 'https://www.9gag.com';
Object.defineProperty(window, 'open', { value: url });

expect(window.open).toEqual(url);

How to reassign window.location in your code base; the simplest working setup we found for our Jest tests:

const realLocation = window.location;

beforeEach(() => {
  delete window.location;
});

afterEach(() => {
  window.location = realLocation;
});