diff --git a/tests/phpunit-autotest.xml b/tests/phpunit-autotest.xml
index cba407dae7..17b0b62c0b 100644
--- a/tests/phpunit-autotest.xml
+++ b/tests/phpunit-autotest.xml
@@ -21,6 +21,7 @@
 				<directory suffix=".php">../3rdparty</directory>
 				<directory suffix=".php">../apps/*/composer</directory>
 				<directory suffix=".php">../apps/*/tests</directory>
+				<directory suffix=".php">../apps/files_external/3rdparty</directory>
 				<directory suffix=".php">../build</directory>
 				<directory suffix=".php">../lib/composer</directory>
 				<directory suffix=".php">../tests</directory>