Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in /home/mohamed/education.mohamed-emad.com/vendor/symfony/type-info/Tests/Type/NullableTypeTest.php:19 Stack trace: #0 {main} thrown in /home/mohamed/education.mohamed-emad.com/vendor/symfony/type-info/Tests/Type/NullableTypeTest.php on line 19