X Server Integration Testing. Yes, it's possible
Aside from the dusty X Test Suite, X server testing tends to be sporadic, manual and ad-hoc. This leads to recurring bugs and breakage that may last several months.
Over the last couple of weeks, I've been working on a test suite based on googletest and xorg-gtest to automate input driver testing, bug replication and general server behaviour. In this talk, I'll give an outline of the current state of this test suite, followed by a discussion on the future direction of this test suite. Amongst the topics to be discussed are scalability, test case design, the requirement for test cases to be added to bug fixes, etc. Audience participation required and appreciated.
See http://who-t.blogspot.de/2012/08/xorg-integration-test-suite.html for more info and (links to) examples