Book Image

Mastering React Test-Driven Development - Second Edition

By : Daniel Irvine
Book Image

Mastering React Test-Driven Development - Second Edition

By: Daniel Irvine

Overview of this book

Test-driven development (TDD) is a programming workflow that helps you build your apps by specifying behavior as automated tests. The TDD workflow future-proofs apps so that they can be modified without fear of breaking existing functionality. Another benefit of TDD is that it helps software development teams communicate their intentions more clearly, by way of test specifications. This book teaches you how to apply TDD when building React apps. You’ll create a sample app using the same React libraries and tools that professional React developers use, such as Jest, React Router, Redux, Relay (GraphQL), Cucumber, and Puppeteer. The TDD workflow is supported by various testing techniques and patterns, which are useful even if you’re not following the TDD process. This book covers these techniques by walking you through the creation of a component test framework. You’ll learn automated testing theory which will help you work with any of the test libraries that are in standard usage today, such as React Testing Library. This second edition has been revised with a stronger focus on concise code examples and has been fully updated for React 18. By the end of this TDD book, you’ll be able to use React, Redux, and GraphQL to develop robust web apps.
Table of Contents (26 chapters)
Part 1 – Exploring the TDD Workflow
Part 2 – Building Application Features
Part 3 – Interactivity
Part 4 – Behavior-Driven Development with Cucumber


In this chapter, you’ve been able to practice the TDD cycle a few times and get a feel for how a feature can be built out using tests as a guide.

We started by designing a quick mock-up that helped us decide our course of action. We have built a container component (AppointmentsDayView) that displayed a list of appointment times, with the ability to display a single Appointment component depending on which appointment time was clicked.

We then proceeded to get a basic list structure in place, then extended it to show the initial Appointment component, and then finally added the onClick behavior.

This testing strategy, of starting with the basic structure, followed by the initial view, and finishing with the event behavior, is a typical strategy for testing components.

We’ve only got a little part of the way to fully building our application. The first few tests of any application are always the hardest and take the longest to write. We are now over...