Setting up unit tests in Angular with Jest

By default, a new Angular project comes bundled with a lot of goodness, including the configuration and tooling in which to run unit tests with Karma and Jasmine. While working with Karma is relatively convenient, many developers find that in large-scale projects, the whole testing process becomes much slower if there are a lot of tests involved. This is mainly because you can't run tests in parallel. In this recipe, we'll set up Jest for unit testing in an Angular app. Additionally, we'll migrate existing tests from the Karma syntax to the Jest syntax.

Getting ready

The project that we are going to work with resides in chapter10/start_here/setting-up-jest, which is inside the cloned repository. To begin, perform the following steps:

1. Open the project in Visual Studio Code.
2. Open the Terminal and run npm install to install the dependencies of the project.
3. Once done, run ng serve -o.

This should open...