Fatal error: Uncaught Error: Class "MediaWikiIntegrationTestCase" not found in /var/www/html/w/extensions/MathSearch/tests/phpunit/integration/WikiTexVC/MMLRefFilesTest.php:15 Stack trace: #0 {main} thrown in /var/www/html/w/extensions/MathSearch/tests/phpunit/integration/WikiTexVC/MMLRefFilesTest.php on line 15