I looked to see if BYU had made the source code available, but it doesn't look like they've published it. It's called code recorder, and before we do an assignment we have to enable recording. It generates a .json file that lists every single edit made in terms of a textual diff. They must have some sort of tool that reconstructs it when they grade. Sorry I don't know more!
Edit: I expect it wouldn't be super hard to create though, you'd just have to hook into the editor's change event, probably compute the diff to make sure you don't lose anything, and then append it to the end of the json.
I looked to see if BYU had made the source code available, but it doesn't look like they've published it. It's called code recorder, and before we do an assignment we have to enable recording. It generates a .json file that lists every single edit made in terms of a textual diff. They must have some sort of tool that reconstructs it when they grade. Sorry I don't know more!
Edit: I expect it wouldn't be super hard to create though, you'd just have to hook into the editor's change event, probably compute the diff to make sure you don't lose anything, and then append it to the end of the json.