Introduction: Automated Testing

Overview

Now, it's time to get our QandA app ready for production. In this chapter, we are going to add automated tests to the frontend and backend of our app, which will give us the confidence to take the next step: moving our app into production.

First, we will focus on the backend and use xUnit to implement unit tests on pure functions with no dependencies. Then, we'll move on to testing our QuestionsController, which does have dependencies. We will also learn how to use Moq to replace our real implementation of dependencies with a fake implementation.

Next, we will turn our attention to testing the frontend of our app with the popular Jest tool. We will learn how to implement unit tests on pure functions and integration tests on React components by leveraging the fantastic React Testing Library.

Then, we will learn how to implement end-to-end tests with Cypress. We'll use this to test a key path through the app where the frontend and backend will be working together.

By the end of this section, our tests will give us more confidence that we are not breaking existing functionality when developing and shipping new versions of our app.