diff --git a/apps/dav/lib/CalDAV/CalDavBackend.php b/apps/dav/lib/CalDAV/CalDavBackend.php
index fc23b6545e514..c57d3a2764f1e 100644
--- a/apps/dav/lib/CalDAV/CalDavBackend.php
+++ b/apps/dav/lib/CalDAV/CalDavBackend.php
@@ -2732,7 +2732,7 @@ protected function addChange(int $calendarId, string $objectUri, int $operation,
 	 * @param string $calendarData
 	 * @return array
 	 */
-	public function getDenormalizedData($calendarData) {
+	public function getDenormalizedData(string $calendarData): array {
 		$vObject = Reader::read($calendarData);
 		$vEvents = [];
 		$componentType = null;
@@ -2746,7 +2746,7 @@ public function getDenormalizedData($calendarData) {
 			if ($component->name !== 'VTIMEZONE') {
 				// Finding all VEVENTs, and track them
 				if ($component->name === 'VEVENT') {
-					array_push($vEvents, $component);
+					$vEvents[] = $component;
 					if ($component->DTSTART) {
 						$hasDTSTART = true;
 					}