Unit testing is a crucial practice in software development that ensures individual components of an application work as expected. This guide covers everything know about unit testing in Node.js, including a comparison between Mocha/Chai and Jest, and information on additional useful packages like Nock, Sinon, Mocha Awesome, NYC, and Chai-HTTP.
Unit testing helps identify issues early in the development cycle when they are easier and cheaper to fix. By writing tests for each unit of code, you can catch bugs as soon as they are introduced, preventing them from propagating to other parts of the application.