I'm fairly new to unit testing. In school it's always been, "hey it works, onward!" But I've started to write professionally, and even at work that's been basically the mantra. However, I've started to see the validity of unit testing and TDD. I've come to a realization, that when I write maybe a 20 line piece of code, I'll usually write a 100-250 lines of code testing those lines of code. Is this about average? Are there better best practices of unit testing that I'm not aware of?
Any way, I thought it was an interesting observation and was wondering, on average how much more code do you write when you write your unit tests?