diff --git a/src/GraphQL/InputMapper/SearchQueryMapper.php b/src/GraphQL/InputMapper/SearchQueryMapper.php
index e1156ce..72ed5c4 100644
--- a/src/GraphQL/InputMapper/SearchQueryMapper.php
+++ b/src/GraphQL/InputMapper/SearchQueryMapper.php
@@ -104,7 +104,7 @@ function ($sortClauseClass) {
      *
      * @return \eZ\Publish\API\Repository\Values\Content\Query\Criterion\DateMetadata[]
      */
-    private function mapDateMetadata(array $queryArg = [], $dateMetadata)
+    private function mapDateMetadata(array $queryArg, $dateMetadata)
     {
         if (!isset($queryArg[$dateMetadata]) || !is_array($queryArg[$dateMetadata])) {
             return [];