I can understand why some projects close bugs due to inactivity, but I was a little surprised to see that it was closed after only a month of idling.

Asking for a code sample test case in this instance is inappropriate, and IMHO is a lazy shirk of one's responsibilities. Sure, if I can't reproduce the bug I'll ask for a test case, but in this situation it was not called for. That's certainly not how I'd treat a user who cared enough to submit a bug in one of my programs.