I think mandatory code formatting was popularized by Go? Plenty of code formatting tools had been around for quite a while by the time Go came out, but they wer

I think mandatory code formatting was popularized by Go? Plenty of code formatting tools had been around for quite a while by the time Go came out, but they were the sort of thing you ran on a codebase once to clean up a mess, not something you checked on each commit. A common sentiment was that it was a good idea but was only viable because Go had it from the beginning, which fortunately turned out to be wrong.