Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in C:\xampp\htdocs\r10csm\vendor\phpunit\php-invoker\tests\InvokerTest.php:21 Stack trace: #0 {main} thrown in C:\xampp\htdocs\r10csm\vendor\phpunit\php-invoker\tests\InvokerTest.php on line 21