Implement TDD for your React applications using Jest, React Router, Redux, and GraphQL/Relay. Learn BDD and end-to-end acceptance testing with CucumberJS and Puppeteer.Learn the TDD process using the React frameworkBuild complex, real-world applications with a pragmatic approach to TDDUse Cucumber for acceptance and BDD testing, bringing TDD to the wider team Many programmers are aware of TDD but struggle to apply it beyond basic examples. This book teaches how to build complex, real-world applications using Test-Driven Development (TDD). It takes a first principles approach to the TDD process using plain Jest and includes test-driving the integration of libraries including React Router, Redux, and Relay (GraphQL). Readers will practice systematic refactoring while building out their own test framework, gaining a deep understanding of TDD tools and techniques. They will learn how to test-drive features such as client- and server-side form validation, data filtering and searching, navigation and user workflow, undo/redo, animation, LocalStorage access, WebSocket communication, and querying GraphQL endpoints. The book covers refactoring codebases to use the React Router and Redux libraries. via TDD. Redux is explored in depth, with reducers, middleware, sagas, and connected React components. The book also covers acceptance testing using Cucumber and Puppeteer. The book is fully up to date with React 16.9 and has in-depth coverage of hooks and the ‘act’ test helper.Build test-driven applications using React 16.9+ and JestBuild complete web applications using a variety of HTML input elementsUnderstand the different types of test double and when to apply themTest-drive the Integration of libraries such as React Router, Redux, and Relay (GraphQL)Learn when to be pragmatic and how to apply TDD shortcutsTest-drive interaction with browser APIs including fetch and WebSocketUse Cucumber.js and Puppeteer to build BDD-style acceptance tests for your applicationsBuild and test async Redux code using redux-saga and expect-reduxThe target audience for this book is JavaScript developers who are looking to implement test-driven and behavior-driven approaches for their React applications.