For MediaWiki core, the PHP code coverage is done twice per day because it takes two hours to generate ( build time trend).
Regardless, 2 hours is way too long and I am tempted to decline this task in our current state. It is potentially solvable though, a few ideas:
- actually spend time speeding up PHP tests
- figure out how to get coverage with HHVM and potentially up PHPUnit (we use Zend / xdebug / PHPUnit 3.x).
- split true unit tests and the integration tests