I have six distributions on the CPAN, yet I've never had a single test fail. I could pat myself on the back, but I do wonder if this is because I didn't write enough tests, skipped corner cases, or in the case of AI::NeuralNet::Simple, I didn't know how to test it (and hence have only 18 tests). A couple of days ago, I finally received a report of a test failure. It was on AI::NeuralNet::Simple. I wasn't surprised because the bulk of the code is written in C, so I naturally assumed that I was going to have some obvious error that a C neophyte like myself had overlooked.
Nope. The module depends Inline::C and a couple of test modules. Somewhere in the modules I use is a dependency on Sub::Uplevel. I haven't tracked down who uses it yet, but I'm kind of bummed out that my perfect (cough) track record was ruined by someone else's module. I don't want to put Sub::Uplevel in my Makefile.PL, so I'll have to get off my rear and find out who left it out of their dependencies.