Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in C:\xampp73\htdocs\MonitoresCIE_C\vendor\sebastian\diff\tests\DiffTest.php:20 Stack trace: #0 {main} thrown in C:\xampp73\htdocs\MonitoresCIE_C\vendor\sebastian\diff\tests\DiffTest.php on line 20