1--TEST-- 2Enum must not implement Serializable 3--FILE-- 4<?php 5 6enum Foo implements Serializable { 7 case Bar; 8 9 public function serialize() { 10 return serialize('Hello'); 11 } 12 13 public function unserialize($data) { 14 return unserialize($data); 15 } 16} 17 18var_dump(unserialize(serialize(Foo::Bar))); 19 20?> 21--EXPECTF-- 22Deprecated: %s implements the Serializable interface, which is deprecated. Implement __serialize() and __unserialize() instead (or in addition, if support for old PHP versions is necessary) in %s on line %d 23 24Fatal error: Enums may not implement the Serializable interface in %s on line %d 25