Fatal error: Uncaught Error: Class "PHPUnit\Framework\TestCase" not found in /users/danielstruebig/www/Dart_software/vendor/mollie/mollie-api-php/tests/Mollie/API/CompatibilityCheckerTest.php:6 Stack trace: #0 {main} thrown in /users/danielstruebig/www/Dart_software/vendor/mollie/mollie-api-php/tests/Mollie/API/CompatibilityCheckerTest.php on line 6