While I wouldn't say it isn't a hack, Vintageous includes tests:
I've abstracted out the testing helpers into their own package:
It should work, but Vintageous still uses the older testing helpers, which are included with Vintageous' code, though I hope to use AAAPT exclusively at some point.
Note that you have to start ST in order to run the tests.
An idea would be to run the tests passing a -command parameter to sublime_text, but I didn't have too much luck last time I tried.
(Also, AAAPT has a funny name because there should be some guarantee that it will be loaded before other packages call it.)