Score one for unit testing.

[Roy Smith]

We've got a test that's been running fine ever since it was written a
month or so ago. Now, it's failing intermittently on our CI (continuous
integration) box, so I took a look.

It turns out it's a stupid test because it depends on pre-existing data
in the database. But, the win is that while looking at the code to
figure out why this was failing, I noticed a completely unrelated bug in
the production code.

See, unit testing helps find bugs

 

[Chris Angelico]

We've got a test that's been running fine ever since it was written a
month or so ago. Now, it's failing intermittently on our CI (continuous
integration) box, so I took a look.

I recommend you solve these problems the way these folks did:

http://thedailywtf.com/Articles/Productive-Testing.aspx

ChrisA