They're also great for remembering what the heck functions do. At one of my jobs we have a file called filters.js which had hundreds of functions in it. I made

They're also great for remembering what the heck functions do. At one of my jobs we have a file called filters.js which had hundreds of functions in it. I made it a rule that anytime I used or added one of these functions in the future I would have to write at least one unit test for it.