Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in E:\xampp\htdocs\key1\vendor\symfony\http-kernel\Tests\Config\EnvParametersResourceTest.php:20 Stack trace: #0 {main} thrown in E:\xampp\htdocs\key1\vendor\symfony\http-kernel\Tests\Config\EnvParametersResourceTest.php on line 20