paulchaplin/jest-environment-jsdom-global

A Jest environment that allows you to configure jsdom

Jest environment for a globally-exposed JSDOM

Similar to the standard jest-environment-jsdom, but exposes jsdom so that you can reconfigure it from your test suites.

For more information, see this discussion in the Jest repository.

Installation and configuration

Install the package with yarn:

yarn add --dev jest-environment-jsdom-global jest-environment-jsdom

or npm:

npm install --save-dev jest-environment-jsdom-global jest-environment-jsdom

Then, add it to your Jest configuration:

"jest": {
  "testEnvironment": "jest-environment-jsdom-global"
}

For more information, see the Jest documentation on testEnvironment.

Using JSDOM in your test suite

You can access the jsdom object globally in your test suite. For example, here's a test that changes the URL for your test environment (using reconfigure):

describe("test suite", () => {
  it("should not fail", () => {
    jsdom.reconfigure({
      url: "https://www.example.com/"
    });
  });
});

Frequently Asked Questions

Why can't I use Object.defineProperty?

Jest's browser environment is based on JSDOM. JSDOM used to allow you to use Object.defineProperty to update certain properties on window; in particular, you could change parts of window.location, or window.top, as you need to.

However, in recent versions, JSDOM's API has changed; the preferred way to mock window.location and its child properties is to use reconfigure. Jest is using version 11 of JSDOM as of Jest 22; as a result, tests that used Object.defineProperty may no longer work on certain properties of window.

Currently, Jest does not expose the JSDOM reconfigure method inside test suites. The jest-environment-jsdom-global package is meant to solve this problem: it adds jsdom as a global, so you can reconfigure it within your tests.

How can I mock window.location.href?

In your test, you can set the URL using:

jsdom.reconfigure({
  url: "https://www.example.com/"
});

How can I mock window.location.hash?

You need to provide a full URL, not just the hash. Similarly to above, you can do:

jsdom.reconfigure({
  url: "https://www.example.com/#myHash"
});