Fatal error: Uncaught Error: Class 'PHPUnit\Framework\TestCase' not found in /opt/lampp/htdocs/vendor/topthink/think-filesystem/tests/FilesystemTest.php:16
Stack trace:
#0 {main}
thrown in /opt/lampp/htdocs/vendor/topthink/think-filesystem/tests/FilesystemTest.php on line 16