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

Automated testing

TDD is a form of automated testing. This section lists some other popular types of automated testing and how they compare to TDD.

Integration tests

These tests check how two or more independent processes interact. Those processes could either be on the same machine or distributed across a network. However, your system should exercise the same communication mechanisms as it would in production, so if it makes HTTP calls out to a web service, then it should do so in your integration tests, regardless of where the web service is running.

Integration tests should be written in the same unit test framework that you use for unit tests, and all of the same rules about writing good unit tests apply to integration tests.

The trickiest part of integration testing is the orchestration code, which involves starting and stopping processes, and waiting for processes to complete their work. Doing that reliably can be difficult.

If you’re choosing to mock objects...