React Unit Testing

We sufficiently discussed the fundamentals of React in the preceding chapters. You have been exposed to React tools and resources to master modern frontend techniques in your full stack development journey. We explored in-depth useful information required to build rich interactive interfaces with React. We discussed the topics of components, props and state, JSX, event handling, forms, and routing in React.

In this chapter, we will focus on unit testing in React applications, a type of software testing that focuses on isolated piece(s) of code. Also, we will explore Jest, a Node-based test runner. The test runner allows you to discover test files, run tests, and find out whether tests passed or failed automatically. You will then end with a report in a very clear, expressive, and human-readable format.

Jest is a popular testing framework developed with React in mind. The project was formally owned by Meta, the same company behind React. However, with the recent...