Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in C:\xampp\htdocs\tests\unit\Packet\ModbusFunction\WriteMultipleRegistersRequestTest.php:12 Stack trace: #0 {main} thrown in C:\xampp\htdocs\tests\unit\Packet\ModbusFunction\WriteMultipleRegistersRequestTest.php on line 12