Jest error when setting or assigning 'window.location'

Question

I upgraded the Jest library to v25 and all unit tests that were checking location change are failing.

I checked a couple of issues opened on the Jest repository, but I didn't actually understand how can this be fixed.

The code that calls location.assign breaks with the following error:

Error: Not implemented: navigation (except hash changes)

      69 |     // window.location.href = url;
    > 70 |     window.location.assign(url);

I suppose that the Jest jsdom window object shouldn't be treated any more like a real browser window with regards to changing the location.

How can I fix this?

---

My findings:

• Navigation in the tests doesn't work. All these methods that work in the browser are not implemented in the JSDom window:
  • window.location.href = "https://myapp.com"
  • window.location.assign("https://myapp.com")
  • window.location.replace("https://myapp.com")
  • Object.defineProperty(window.location, "href", { writable: true, value: currentUrl }); window.location has been set as Unforgeable

To fix failing tests I used:

1. window.history.pushState({}, "title", "/testJest");

2. delete window.location; window.location = { assign: jest.fn() };

   it("should navigate to the new URL", () => { const myUrl = "http://some.url"; expect(window.location.assign).toHaveBeenCalledWith(myUrl); });

Answer 1

Just add the following code in your test file.

  Object.defineProperty(window, 'location', {
    writable: true,
    value: { assign: jest.fn() }
  });

Answer 2

To keep it short, "global" is "window" in Jest.

Use:

global.location.assign(url);

I believe that you can find the rest of the answer in How can I mock the JavaScript window object using Jest?.

Also, there is an interesting conversation around this on this issue:

I found window is global in Jest from Stack Overflow, but not mentioned in documentation #3692

Answer 3

Following worked for me:

    window.history.replaceState({}, "", decodeURIComponent(url));

happy coding :)