Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in /home/demoinvfsanz/public_html/vendor/myclabs/deep-copy/tests/DeepCopyTest/Filter/KeepFilterTest.php:12 Stack trace: #0 {main} thrown in /home/demoinvfsanz/public_html/vendor/myclabs/deep-copy/tests/DeepCopyTest/Filter/KeepFilterTest.php on line 12