Configure Jest - JavaScript - Node.js - Express - No commentary

If you are a javascript developer on the backend side, you need to write unit tests in a daily basis. One of the most popular library for doing unit tests in the Node.js ecosystem is Jest. It's a pretty decent solution, but it has not an easy configuration curve, so I made this short example to make it simple for you.

TypeScripted version: https://youtu.be/M-8i6bJRK4k

0:00 - Start
0:40 - Init new project
1:21 - Install dependencies
2:18 - Define "start" npm command
2:48 - Add first route / endpoint
3:06 - Route function
4:12 - Wire route function into the application
4:30 - Start application
5:00 - First attempt to call the endpoint - failed
5:13 - Fix the mistake in the path
5:19 - Second attempt to call the endpoint - success
5:16 - Add Jest configuration file
6:39 - Define "test" npm command uses the Jest configuration file
7:00 - Create first test suite
10:11 - Run tests - error failed
10:24 - Fix wrong expected users array
10:36 - Run tests again - green result

Jest: https://jestjs.io/
Express.js: https://expressjs.com/
Node.js: https://nodejs.org/en/

Source code: https://github.com/davidcsejtei/jest-express-example

Udemy profile: https://www.udemy.com/user/david-csejtei/
LinkedIn profile: https://www.linkedin.com/in/davidcsejtei/
Medium profile: https://codinglikedavid.medium.com/

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