Book Image

Simplify Testing with React Testing Library

By : Scottie Crump
Book Image

Simplify Testing with React Testing Library

By: Scottie Crump

Overview of this book

React Testing Library (RTL) is a lightweight and easy-to-use tool for testing the document object model (DOM) output of components. This book will show you how to use this modern, user-friendly tool to test React components, reducing the risk that your application will not work as expected in production. The book demonstrates code snippets that will allow you to implement RTL easily, helping you to understand the guiding principles of the DOM Testing Library to write tests from the perspective of the user. You'll explore the advantages of testing components from the perspective of individuals who will actually use your components, and use test-driven development (TDD) to drive the process of writing tests. As you advance, you'll discover how to add RTL to React projects, test components using the Context API, and also learn how to write user interface (UI) end-to-end tests using the popular Cypress library. Throughout this book, you’ll work with practical examples and useful explanations to be able to confidently create tests that don't break when changes are made. By the end of this React book, you will have learned all you need to be able to test React components confidently.
Table of Contents (10 chapters)

Testing implementation details

Implementation details include the component state's current value or explicitly invoking a method attached to a button in the DOM. Implementation details are the under-the-hood parts of components abstracted away from the user when they use the component. As an analogy, we can think of the experience of driving a car. To move, you must use the key to start the car, put the car into drive, and press the gas pedal. You don't need to know how everything is wired together in the engine under the vehicle's hood. You probably do not even care. All you care about is that you can drive the car when you perform the behaviors mentioned.

In this section, you will explore the disadvantages of focusing on implementation details in your tests. We will show you examples of tests with implementation details. Finally, you will learn how to shift your focus away from thinking about implementation details when testing.

Problems with implementation...