I have my master branch set up to track the master branch of my fork (mainly because i don't want to accidentally pull in every git tag into my shallow clone), so upstream/master doesn't updated when i run git pull (presumably the upstream remote was created by ./x setup? i don't remember creating it, and lots of code needs it (or another branch pointing to this repo) to work).

as it turns out, ./x fmt uses the state of upstream/master to determine if a file has been modified. so instead of it formatting every file that i modified, it formats every file anyone has modified in the last few months.

at no point did anything warn me that i need to be updating a remote i didn't add. it should probably do that.