Comment 4 for bug 1655671

Our GH CI is basically autopkgtest, and its exactly what gets run on autopkgtest.ubuntu.com for package promotion (which is nice, because you know if it passes our CI, barring any weirdness, it will promote).

To run our ci, just create a source package (e.g. using `gbp buildpackage -S`) and then run `autopkgtest ubuntu-image_*.dsc`. For best results, use autopkgtest-buildvm-ubuntu-cloud to create a bootable image of whatever distroversion you want to test (zesty, yakkety, xenial), and use the qemu autopkgtest backend with this image. Many of the tests require an isolation level that only a VM can provide.

All that means that you'd need to write a debian/tests/foo file (and update debian/tests/control) to run this new CI test, but I think it could be pretty simple. It would just do a git diff/stat against master and make sure that d/changelog was touched. There are some complications though:

* This test should only ever run on PRs; it should not run when already on the master branch, since there will be no diff against master!

* There should be a way to explicitly skip this test on a PR. Some changes are too minor to be mentioned in the changelog, and that's fine, but I would like it to be an explicit bypass. Unfortunately, I haven't thought of a good way to do that that doesn't also leave cruft in our tree. That's been the hangup for me so far, but if you have any thoughts, let's discuss!