Test-Driven Development 101 with jest

This excerpt is from my book Test-Driven Development with React. It is the fundamental part of the book — about applying TDD with an end-to-end example, follow this link for more details.

In this chapter, we will learn together about how to apply TDD in your daily development routine by a step-to-step guide. Along with this demo, you will get the idea of how to split a big task into relative smaller ones, and accomplish each one with a set of passing tests and a bit refactoring techniques. Just before we dive into the code, let's get some fundamental understanding…