Singing the praises of continuous integration
One thing that almost every project seems to struggle with is unit testing. Not so much the writing of said tests as much as the fact that inevitably you will get really busy and no one will run all of the unit tests for a week or so, and then all of a sudden you decide to run them and you find out that half of them are failing.
Many times these are easy to fix, but when there are so many failing, you don’t have time to dive in and fix them all. So no one fixes them, and the unit tests become pretty much worthless because you can’t count on any of them.
At this point, many people stop writing unit tests because they’re not used to ever running unit tests anymore, so they forget about writing them altogether.
Someone will eventually decide that the unit tests need to be fixed, so someone will spend an entire week fixing them all up. But by then the code coverage is lacking because people had stopped writing them (see above). You don’t have time to add tests at that point because you’re a week behind because you spent a week fixing unit tests.
For the first time I am working on a project where none of this is happening. Much of the credit goes to my co-workers, who do a great job of writing lots of good tests and keeping them up. But what is going to keep everything going is using continuous integration with TFS 2008.
I know, some people are getting ready to click the comment button and say that they’ve been doing CI with CruiseControl for years. CruiseControl is great, I won’t deny that.
Much to my surprise, it took me no more than 10 minutes to set up our CI build using TFS 2008. Now I can look at a dashboard screen and see that all 684 of our unit tests have been passing all day. If a check-in causes a test to break, everyone gets an email saying so and TFS automatically creates a bug for the person that broke it. So we stop and fix the tests right away and we get back to work.
Next up is to figure out how can configure our USB Missile Launcher to automatically shoot someone when they break the tests!