End-to-end testing is awesome because it mirrors the user’s experience. Where you might need a ton of unit tests to get good coverage (the kind where you test that a function returns a value you expect), you can write a single end-to-end test that acts like a real human as it tests several pieces of your app at once. It’s a very economical way of testing your app.
Cypress is a new-ish test runner with some features that take some of the friction out of end-to-end testing. It sports the ability to automatically wait for elements (if you try to grab onto an element it can’t find), wait for Ajax requests, great visibility into your test outcomes, and an easy-to-use API.
We use Cypress for our own in-house testing, so when I saw the post on CSS-Tricks, I wanted to share it.