Setting up the environment
We have covered the simple unit test on the frontend JavaScript with different frameworks in our previous chapters. When it comes to unit testing the code on the server side, we mostly remain unaware of the order in which the functions will be called, we may either try to run the tests in a callback, or we might be interested in checking asynchronous behavior in the functions.
We have lots of frameworks available in the market for testing a server-side code as JUnit, PHPUnit, NUnit, QUnit, Mocha, and other frameworks for server-side code testing. We will use Mocha along with Node.js in this chapter to understand the server side testing with JS. Most of the unit testing frameworks are similar in the features that they provide, and a choice must be made as per the project and the comfort of the team.
In a project, classes are usually models and helper classes contain business logics. For server-side testing, we usually write unit tests for components with business...
