Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in E:\xampp\htdocs\www\key\vendor\symfony\console\Tests\Formatter\OutputFormatterStyleTest.php:17 Stack trace: #0 {main} thrown in E:\xampp\htdocs\www\key\vendor\symfony\console\Tests\Formatter\OutputFormatterStyleTest.php on line 17