This is my browser clone of the jest framework, I wrote this at a time when there was no native ES6 module support, I had used jest previously and really liked the syntax so i tried to make this project nearly one for one with jest syntax.
About the project
This project was the culmination of two frustrations.
I Couldn't fully wrap my head around the Jest testing library.
It was a chore to get it working in a ES6 Environment without using babel and other tools.
Now problem 2 was recently solved by the Jest Team with ES6 module support.
But I had problem 1 to deal with.
This project was a fantastic exercise in making code to spec.
I made the entirety of this projects testing functions , to replicate as closely as possible Jest's documented behaviors.
My goal was never to write a competitor for jest but rather to write a test library I could use while I waited for Jest to support how I make projects.
If you are ever in a position to attempt something like this for one of your favorite libraries I would highly recommend it.
I was able to get a MUCH better understanding of not only where Jest was useful but also how it works under the hood.
This not only increased my proficiency in writing tests but also greatly increased my appreciation for what Jest does for me behind the curtain.
I have since gained a immense satisfaction from writing good tests for my programming projects and having that safety net in place for when I add new code or refactor old code.