1--TEST-- 2References to objects for which Serializable::serialize() returned NULL should use N; 3--FILE-- 4<?php 5 6class NotSerializable implements Serializable { 7 public function serialize() { 8 return null; 9 } 10 11 public function unserialize($serialized) { 12 } 13} 14 15$obj = new NotSerializable(); 16$data = [$obj, $obj]; 17var_dump($s = serialize($data)); 18var_dump(unserialize($s)); 19 20?> 21--EXPECT-- 22string(18) "a:2:{i:0;N;i:1;N;}" 23array(2) { 24 [0]=> 25 NULL 26 [1]=> 27 NULL 28} 29