By default, the JSDOM constructor will return an instance with an empty cookie jar. by doing global.window = dom.window), and then executing scripts or test code inside the Node global environment. For example, here is a version that only returns results for requests to a trusted origin: jsdom will call your custom resource loader's fetch() method whenever it encounters a "usable" resource, per the above section. Unneeded HTTP headers . When starting a new Angular application, the Angular CLI sets up everything you need for unit testing using Karma and Jasmine. On those occasions when using DOM is required (e.g. To make it easier to debug, you can use jsdom-devtools-formatter, which lets you inspect them like real DOM elements. They’re highly-focused, covering only the concepts you want to learn so that you can level up your skills and get on with the rest of your day. It includes: Let's say we've generated an Angular application called my-app with the following command: The jest.config.js holds Jest's configuration. To use jsdom, you will primarily use the JSDOM constructor, which is a named export of the jsdom main module. jsdom's primary target is still Node.js, and so we use language features that are only present in recent Node.js versions (namely, Node.js v8+). TypeScript configuration hints set . This can be worked around in a few ways. Like web browsers, jsdom has the concept of a "console". I’ll update the Gist. I’d lose the internal logic of the Location object. However, when I was recently upgraded a repo from Jest 23 to Jest 26, this no longer worked. Jest v23 was released in May 2018 and the headline of this release was “Blazing Fast Delightful Testing”. This might require, for example, creating a browserify bundle to execute as a