PHPUnit 5.7 is the old stable release series.
It became stable on December 2, 2016.
Support for PHPUnit 5 ends on February 2, 2018.
— https://phpunit.de/
Coverage remained the same at 100.0% when pulling e18083f0d3d0cc77710c8dcb0827f91b9efafb95 on foaly-nr1:phpunit6 into 491c47f0eecc9f7471dec0cb97d6f1f97cad0127 on kleijnweb:master.