12. Unit Testing

Overview

In this chapter, we will look at approaches to unit testing Vue.js applications in order to improve our quality and speed of delivery. We will also look at using tests to drive development using Test-Driven Development (TDD).

As we proceed, you will gain an understanding of why code needs to be tested and what kinds of testing can be employed on different parts of a Vue.js application. You will see how to unit test isolated components and their methods using shallow rendering and vue-test-utils, and you will learn how to test asynchronous component code. Throughout the course of the chapter, you will gain familiarity with techniques to write efficient unit tests for mixins and filters. Toward the end of the chapter, you will become familiar with approaches to testing a Vue.js applications that includes routing and Vuex, and you will learn about using snapshot tests to validate your user interface.