Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in C:\xampp\htdocs\r10ca\vendor\sebastian\code-unit\tests\unit\FunctionUnitTest.php:25 Stack trace: #0 {main} thrown in C:\xampp\htdocs\r10ca\vendor\sebastian\code-unit\tests\unit\FunctionUnitTest.php on line 25