Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in C:\xampp\htdocs\CnVideosSite\vendor\topthink\framework\tests\CacheTest.php:15 Stack trace: #0 {main} thrown in C:\xampp\htdocs\CnVideosSite\vendor\topthink\framework\tests\CacheTest.php on line 15