Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in C:\xampp\htdocs\tests\unit\Composer\Write\Register\StringWriteRegisterAddressTest.php:10 Stack trace: #0 {main} thrown in C:\xampp\htdocs\tests\unit\Composer\Write\Register\StringWriteRegisterAddressTest.php on line 10