diff --git a/tests/lib/SimpleSAML/Auth/SourceTest.php b/tests/lib/SimpleSAML/Auth/SourceTest.php
index 42799c77c0f7ad2a8f135539ac29feb327734d4c..0cbf1e849027d7bf63493d449160591915dad832 100644
--- a/tests/lib/SimpleSAML/Auth/SourceTest.php
+++ b/tests/lib/SimpleSAML/Auth/SourceTest.php
@@ -28,7 +28,7 @@ class SourceTest extends ClearStateTestCase
 
 class TestAuthSource extends \SimpleSAML_Auth_Source
 {
-    public function authenticate(array &$state)
+    public function authenticate(&$state)
     {
     }
 }