Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in C:\xampp\htdocs\print\vendor\symfony\var-dumper\Tests\Dumper\HtmlDumperTest.php:21 Stack trace: #0 {main} thrown in C:\xampp\htdocs\print\vendor\symfony\var-dumper\Tests\Dumper\HtmlDumperTest.php on line 21