So, as a follow-up to the original silly-formatting post, I spent some time trying to figure out just how bad the LALRPOP-based sillyfmt implementation was. It turns out that there’s really nice utilities for using the afl fuzzer with Rust, so I hooked that up with some pretty basic heuristics and let it run for a few seconds. Then, since it turned out to be really bad, I got nerd-sniped into setting up a different parser called tree-sitter that uses a more generic parsing algorithm.