Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in /home/edmedu/www/edmeducation.co.kr/tw-dev/vendor/sebastian/diff/tests/DiffTest.php:20 Stack trace: #0 {main} thrown in /home/edmedu/www/edmeducation.co.kr/tw-dev/vendor/sebastian/diff/tests/DiffTest.php on line 20