diff --git a/Tests/Functional/Common/SolrIndexingTest.php b/Tests/Functional/Common/SolrIndexingTest.php
index 002e75f122..07d092d4fb 100644
--- a/Tests/Functional/Common/SolrIndexingTest.php
+++ b/Tests/Functional/Common/SolrIndexingTest.php
@@ -137,7 +137,9 @@ public function canSearchInCollections()
         $collections = $this->collectionRepository->findCollectionsBySettings([
             'index_name' => ['Musik', 'Projekt: Dresdner Hefte'],
         ]);
+        $music = [];
         $music[] = $collections[0];
+        $dresdnerHefte = [];
         $dresdnerHefte[] = $collections[1];
 
         $settings = [