Currently there has been movement to start continuous integration of Plone addons on Travis CI service. I have seen a lot of packages doing their own this and that testing, from running unit tests to do source code linting of merge requests. I see this healthy development as it takes the pain of setting up your own test runner and makes it easier for less Python-sawy community members to have tests run for their patches.
However, I have not found a definite guide of best practices how one should test his/her addon on Travis CI. At least in my case this has resulted to cargo cult programming and copy-pasting code from other random addons, because I don't know what's available and how one should do it.
Could authors, who have insight how Travis CI and Plone testing works clarify
What kind of tests you should run on Travis CI
How you should run these tests, in particulary in the context of collective package
What are the best examples you should look into
Where these practices are or should be documented*
How one should test against multiple Plone versions, or is it possbile
Where to pipe the result? Personal email?
*) Traditional Finnish carrot provided for those who open their text editor and spend five minutes to dump the contents of their brain