Fatal error: Uncaught Error: Class "PHPUnit\Framework\Constraint\Constraint" not found in C:\Apache24_x64\htdocs\ipad\vendor\symfony\http-foundation\Test\Constraint\ResponseHasHeader.php:17 Stack trace: #0 {main} thrown in C:\Apache24_x64\htdocs\ipad\vendor\symfony\http-foundation\Test\Constraint\ResponseHasHeader.php on line 17