Sorry about that, I just need to rant a little...
Here's what's got me so upset; TDD is a great cool thing. Everybody should be doing it. It's just the best thing since sliced bread, fluffy puppies and free Wi-Fi as Starbucks all rolled into one.
Now, I am NOT a TDD guru by any means. I've read some articles, tried rolling it into my approach and have had great results. I learn a little more everyday, and my understanding increases over time. If you really want to geek out on it you should talk to guys like Steve Harman and Jay Wren!
But there is an evil specter lurking that is threatening to ruin it all.
Well, maybe not code coverage, but the way people with only a passing knowledge of TDD cling to code coverage like it's the last Red Bull in the fridge. The people who don't understand that the point of unit testing is not to increase code coverage at all cost, but to ensure your code does exactly what it is supposed to do; no more and no less.
I come not to bury code coverage, it's a perfect way to see what code is being tested, and more importantly what code is not being tested.
Here's where I get frustrated with peoples attitudes to code coverage (henceforth referred to at CC because I'm a lazy typist); there is a perception that a high CC number will guarantee quality code. That's simply not the case as you can hide a lot of skeletons behind a big enough door.
One "trick" I've seen to increase CC is to simply test EVERY method on the public interface of an object. This sucks.
My philosophy is that I really don't care about the individual gets/sets on a class. And to be honest, I don't like explicit tests of public methods on entities either. My belief is that you test the features. If you then find that there are methods and properties on a class that aren't being covered you have two options; either your tests suck or you don't need that property/method.
So maybe your tests suck. The best way around that is to make sure you write your tests first, THEN write your code. If you approach your tests like you approach your business requirements (user stories drive unit tests maybe?) and your test are meaningful this shouldn't be a problem, right?
Or maybe you don't need the property/method in question. I'm a big fan of pruning classes. If there is a method property on a class that never gets used why keep it? It sits there like a parasite, consuming maintenance costs and provides nothing in return. I say get rid of it!
We as developers/architects/information workers/whatever need to educate ourselves, our co-workers and are clients on this. High CC is NOT a panacea! The quality and intelligence of your tests is what ensures you are not developing crap-ware! Please, write your tests first, make sure all the features you develop are well tested. Review your co-workers tests and have them review yours. And if a high CC number is your goal look at what you are testing and don't be afraid to trim unused code!
OK, I feel better now. Code on!