PHPUnit version 7.3 adds a new argument `--cache-result` which allows you to do awesome things like re-run test failures using a command like:
`phpunit --cache-result --order-by=defects --stop-on-defect`
The cache file is stored as `.phpunit.result.cache`
I believe PHPUnit 8 will have caching on by default, so this file will start popping up in everyone's project quickly.
Caleb Porzio