Question on JS testing for Polyfills
First off, I'm not great at testing; I'll come right out and say that. But I've had a few issues lately and am curious how I'd automate testing to safeguard features. Here's the scenario:
On the beta signup form for DayTrip, I wanted to use the new
fetch() API as a replacement for jQuery and
$.ajax. Using this across all browsers requires two polyfills, a Fetch Polyfill and a Promises Polyfill. The form has has broken twice now which is not ideal for a new product.
- First time was just ignorance, didn't realize I needed a Promise polyfill for some modern browsers, even tho that's documented on the Fetch polyfill.
- Second time was a botched Asset Pipeline. The polyfills weren't included in my
home.js, maybe due switching to
rails_12factor, still not sure.
Another similar situation I have is with the
Different browers need different levels of polyfilling. So my question is this:
- Is it possible to automate testing that necessary polyfills exist as apart of an Integration test?
- Is it possible to automate that across multiple platforms and browsers? Or is the only way to test to manually click through each
formon each browser?
- Even if I did the testing and the Asset Pipeline didn't inclulde and minify the correct files, would JS testing be able to detect that?
- Is this out of scope for what I should be testing? What's a better way?
I would do something along the lines of https://www.jonathanfielding.com/unit-test-your-code-across-multiple-browsers-with-browserstack/: Writing a test (using QUnit, e.g.) and running it on a service like Browserstack or Saucelabs. Ideally integrated with a CI environment like Travis.