Well, just because its a package, doesn't mean it would flawless. Yes the probability so less for something breaking down, but there still could be. So I would write tests if its feasible.
Check out this repo. It shows how the test took place. https://github.com/bradenkeith/testing-nova
There are already a lot more packages for nova testing and discussions over different platforms, you should check them out too, if you haven't. (: