Unit testing is not the answer to everything, but it sure as hell does prevent a few embarrassing and mind numbing situations. Sometimes, no matter how careful you are when programming, some bugs go unnoticed and the simplest way to catch them before anyone else is unit testing.

In this guide, I will show you how to unit test your MERN stack’s backend using Jest. Specifically, Node.js and Mongoose.

If you’re experienced with Node.js then you can skip to Step 2 which details how to test your functions.

Step 1. Set up express backend

Step 2. Install Jest and mongodb-memory-server

Step 3. Handle in-memory Server

Step 4. Set up the test file

Step 5. Anatomy of a Test in Jest

Step 6. Testing createRestaurant()

Step 7. Running Tests

#mongodb #jest #tdd #node