Outside-In React Development : A TDD Primer
Josh JusticeLearn how to build React apps using outside-in test-driven development, including end-to-end tests with Cypress and unit tests with Jest and React Testing Library. Includes an extended exercise building two application features. See how outside-in TDD leads to a thorough test suite, better regression safety, and a faster development speed
How should we decide what kinds of tests to write for our React applications, and how many of each kind? How can we write a test suite that gives us confidence rather than just giving us busywork? Instead of tests slowing down our development, could they actually help us go faster?
Outside-In React Development tackles these questions by applying the practice of outside-in test-driven development (TDD) to React applications. It explains the problems that agile software development solves, the key role that test-driven development plays, and the way outside-in test-driven development helps end-to-end tests and unit tests to work together.
The main part of the book is an extended exercise building a React front-end application from scratch using outside-in TDD. You'll learn
How and why to get your app tested on CI and automatically deploying before the first feature is written
How to use the two-level TDD loop to stay laser-focused on building out one user-deliverable feature to completion
How to write tests that provide maximum safety with minimum ongoing cost by testing the interface instead of the implementation
How to get thorough coverage of edge cases while keeping your test suite fast