Fatal error: Uncaught Error: Class 'Symfony\Component\HttpFoundation\Tests\ResponseTestCase' not found in E:\xampp\htdocs\www\key\vendor\symfony\http-foundation\Tests\ResponseTest.php:20 Stack trace: #0 {main} thrown in E:\xampp\htdocs\www\key\vendor\symfony\http-foundation\Tests\ResponseTest.php on line 20