$re = '/^.*\/(.*)\.py.*::(.*?(\[.*?\])?)$/m';
$str = 'CERTIFICATION/repos_1/test_examples_1_01_C.py::test_case[6]
CERTIFICATION/repos_1/test_examples_2_01_C.py::test_case[7]
INTEGRATION/test_example_scan_1.py::test_case
INTEGRATION/test_example_scan_2.py::test_case';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php