Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in C:\xampp\htdocs\r10ca\vendor\symfony\var-dumper\Tests\Dumper\CliDumperTest.php:28 Stack trace: #0 {main} thrown in C:\xampp\htdocs\r10ca\vendor\symfony\var-dumper\Tests\Dumper\CliDumperTest.php on line 28