Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in C:\xampp\htdocs\xlsss\vendor - Copy\maennchen\zipstream-php\test\BigintTest.php:10 Stack trace: #0 {main} thrown in C:\xampp\htdocs\xlsss\vendor - Copy\maennchen\zipstream-php\test\BigintTest.php on line 10