Introduction

In this chapter, we will look at the purpose and approaches to testing Vue.js applications effectively.

In previous chapters, we saw how to build reasonably complex Vue.js applications. This chapter is about testing them to maintain code quality and prevent defects.

Unit testing will allow us to write fast and specific tests that we can develop against and ensure that features don't exhibit unwanted behavior. We'll see how to write unit tests for different parts of a Vue.js application, such as components, mixins, filters, and routing. We will use tools supported by the Vue.js core team, such as vue-test-utils, and tools supported by the rest of the open source community, such as the Vue Testing library and the Jest testing framework. These different tools will serve to illustrate different philosophies and approaches to unit testing.