generalized conditions for saving entities with chunks

src/pocketmine/level/format/Chunk.php

@@ -667,6 +667,13 @@ class Chunk{
 		return $this->entities;
 	}
 
+	/**
+	 * @return Entity[]
+	 */
+	public function getSavableEntities() : array{
+		return array_filter($this->entities, function(Entity $entity) : bool{ return $entity->canSaveWithChunk() and !$entity->isClosed(); });
+	}
+
 	/**
 	 * @return Tile[]
 	 */