I spent my morning digging into google mug and came away with a fun debugging story.
While reading through their dot parse regex engine I noticed malformed escape sequences like incomplete unicode or empty character names were quietly passing through. A broad fallback rule was catching them and turning them into plain letters.
Looking deeper into the test folder I found an entire suite of error tests that had never been running in ci simply because the file name had a plural s at the end.
I renamed the test file so maven would pick it up, tightened the escape parser rules, and opened a pull request.
The lead maintainer reviewed it within hours, suggested adding a few more characters to the exclusion set to catch property edge cases, and merged the whole thing.
Fixing a silent parsing bug and bringing seventy tests back to life in one morning felt pretty sweet.
You can check out the merged pull request here: https://github.com/google/mug/pull/130
