Testing tutorials needed

I know testing is not the sexiest thing but it is great when you have it because you can prevent regressions and focus on building, not fixing. However, I have found it difficult to find any sort of information on testing, especially 2D. I've been trying to test my collisions of 2D platforms and am no closer after a few days of work. Unity does have a few tutorials here (E2E) and here (Unit) but they are not comprehensive scenarios, nor are they really meant to be. Has anybody come across any good testing scenarios?

 

Here's a link I found recently. Don't know if this might be helpful, but I thought I'd share.
http://honkbarkstudios.com/page/2/