The meta/lib/patchtest/selftest/selftest script should be run periodically on the autobuilder. This will help ensure that as the code is improved, no unintended functional changes or errors will arise in the test suite.
This has been done for some time. It's running here: https://autobuilder.yoctoproject.org/typhoon/#/builders/162 Merged in: https://git.yoctoproject.org/yocto-autobuilder-helper/commit/?id=3ac995a39f9f01527ceb591421c22332b019da84