Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in C:\xampp\htdocs\com.arbokcorp.app\vendor\theseer\tokenizer\tests\XMLSerializerTest.php:9 Stack trace: #0 {main} thrown in C:\xampp\htdocs\com.arbokcorp.app\vendor\theseer\tokenizer\tests\XMLSerializerTest.php on line 9