Perhaps, one of the most important tools in the React ecosystem is Jest—a test runner and unit test library for testing your React components. Jest was designed to overcome challenges faced with other test frameworks like Jasmine, and was created with React development in mind. With powerful testing tools like Jest, you're better equipped to let your unit tests influence the design of your React components. In this chapter, you'll learn:
- The overarching design philosophy of Jest and what this means for React developers
- Running Jest unit tests in a create-react-app environment and in a standalone React environment
- Writing effective unit tests and suites using the Jest API
- Running Jest unit tests in your code editor and integrating tests into your development server