Building open source software can be lots of fun. For some reason, it brings me way too much joy seeing code coverage and tests run on every push to github. It doesn't need to be hard to setup! I'm going to show you how to add automated testing and code coverage reporting to your apps and libraries for every push, pull request, and merge! Here's what we need to get started:
Jest is the best test runner out there right now. It may not be the absolute fastest, but it has the easiest and most useful features that you're going to need. If you use mocha, you'll end up installing istanbul or something else that will run coverage. You want snapshot testing? Jest has that built in too.
... read the whole story at zach.codes.