diff --git a/lib/Share/Helper/FilesMetadataCache.php b/lib/Share/Helper/FilesMetadataCache.php
index 587d2a7066c..e7612bab66e 100644
--- a/lib/Share/Helper/FilesMetadataCache.php
+++ b/lib/Share/Helper/FilesMetadataCache.php
@@ -70,11 +70,12 @@ public function getMetadataPhotosSizeForFileId(int $fileId): array {
 			}
 		}
 
-		if ($this->filesSizeData[$fileId] === null) {
+		$data = $this->filesSizeData[$fileId];
+		if ($data === null) {
 			throw new FilesMetadataNotFoundException();
 		}
 
-		return $this->filesSizeData[$fileId];
+		return $data;
 	}
 
 	protected function cachePhotosSize(int $fileId, IFilesMetadata $metadata): void {