A costly kind of typo

I just spent two hours or more to fix a bug in the software that I am writing. In the end, the problem was that I was suppose to name a file "SomeInsanelyLongNameThatOnlyAProgrammerWouldUse.hbm.xml", but I misnamed it "SomeInsanelyLongNameThatOnlyAProgrammerWouldUse.xml". What a drag!