1--TEST-- 2Serializable deprecation 3--FILE-- 4<?php 5 6interface I extends Serializable {} 7abstract class A implements Serializable {} 8 9class C extends A implements I { 10 public function serialize(): string {} 11 public function unserialize(string $data) {} 12} 13 14class D extends A implements I { 15 public function serialize(): string {} 16 public function unserialize(string $data) {} 17 public function __serialize(): array {} 18 public function __unserialize(array $data) {} 19} 20 21?> 22--EXPECTF-- 23Deprecated: %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 24