Introduction

In the previous chapter, we learned about host platform interoperability (inter-op) in Clojure. We explored how to use Java code in Clojure and JavaScript in ClojureScript. During our inter-op adventure, we created a coffee-ordering application. The application has various features, such as displaying a menu with coffee choices and ordering a coffee. We ran the code and we saw the application working. It is now time to learn about testing in Clojure.

Clojure was designed from the beginning to be a very practical language. Getting things done means interacting with the outside world, building projects, using libraries, and deploying your work. We need to be confident that the code that we write does what it is supposed to do. As a developer, you will need to test your applications. In this chapter, we will see what types of tests can be used. We will look at unit tests as they are the most common type of test written by developers.

Consider a situation where we have...