Fatal error: Uncaught Error: Class "Interop\Http\Factory\StreamFactoryTestCase" not found in C:\xampp\htdocs\vendor\slim\psr7\tests\Factory\StreamFactoryTest.php:18 Stack trace: #0 {main} thrown in C:\xampp\htdocs\vendor\slim\psr7\tests\Factory\StreamFactoryTest.php on line 18