Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in C:\xampp\htdocs\cms-propay\vendor\webklex\php-imap\tests\ClientTest.php:30 Stack trace: #0 {main} thrown in C:\xampp\htdocs\cms-propay\vendor\webklex\php-imap\tests\ClientTest.php on line 30