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