Question: I'm working on a codebase with multiple blocks of code setting some behavior on document.ready() (jQuery). Is there a way to enforce that one specific block is called before any of the others? 

Background:
I need to detect JS errors in an automated testing environment, so I need the code that starts logging JS errors to execute before any other JS code executes.

Answer: 
You should be able to use [holdReady](http://api.jquery.com/jQuery.holdReady/) to do this. As long as it is included before your ready events, you can run your own code and then trigger the other ready events.
I was trying to do something similar, I was loading a bunch of polyfills that had .ready() functions, but I also had my own .ready()s on page that I needed executed first, though the polyfills were loaded in the header.

I found a nice way around it by having a .ready() very early on (right after jQuery loads) that executes functions from an array. Because it's very early in the source code it's .ready() is executed first. Further down the page I can add functions to the array and, so they all execute before any other .ready()s.

I've wrapped it up in a .beforeReady() function and put it on GitHub as jQuery-Before-Ready for anyone that is interested. 
<https://github.com/aim12340/jQuery-Before-Ready>