Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in /var/www/html/autocar/vendor/phpdocumentor/graphviz/tests/phpDocumentor/GraphViz/Test/AttributeTest.php:22 Stack trace: #0 {main} thrown in /var/www/html/autocar/vendor/phpdocumentor/graphviz/tests/phpDocumentor/GraphViz/Test/AttributeTest.php on line 22