Option --test-suite: cannot be empty Usage: php -f phpunitGroupConfig.php [--get-total] Option takes no value, when specified, script will return total number of groups for the test suite specified in --test-suite. It's the default if both --get-total and --get-group are specified or both --get-total and --get-group are not specified. [--get-group="|all"] When option takes a positive integer value , script will generate phpunit_.xml file in the same location as the config file specified in --configuration with a test suite named "group_" which contains the i-th group of tests from the test suite specified in --test-suite. When option takes value "all", script will generate config files for all groups at once. --test-suite="" Name of test suite to be splitted into groups. --group-size="" Number of tests per group. --configuration="" Path to phpunit configuration xml or xml.dist file. [--isolate-tests=""] Path to a text file containing tests that require group isolation. One test path per line. Note: Script uses getopt() which does not accept " "(space) as a separator for optional values. Use "=" for [--get-group] and [--isolate-tests] instead. See https://www.php.net/manual/en/function.getopt.php