$ port installed php73-redis
Password:
  php73-redis @4.2.0_0
  php73-redis @4.2.0_0+debug (active)

$ vendor/bin/phpunit -c cache/stores/redis
Moodle 3.8dev (Build: 20190824), 01d6f0ed663e3abb72ba96e6b4cec15c603342d4
Php: 7.3.7, pgsql: 9.6.14, OS: Darwin 18.7.0 x86_64
PHPUnit 7.5.14 by Sebastian Bergmann and contributors.

.....                                                               5 / 5 (100%)

Time: 1.25 seconds, Memory: 44.00 MB