Online PHP editor | output for TZk8B

@ 2017-01-27T23:35:11Z

<?php
# Acknowledging Stas Malyshev
# https://phabricator.wikimedia.org/T156364#2977719

# Given two classes with the same property name but different visibility
class WithPublic {
	public $property;
	function __construct( $p ) { $this->property = $p; }
	function getProperty() { print $this->property; }
}
class WithPrivate {
	private $property;
	function __construct( $p ) { $this->property = $p; }
	function getProperty() { print $this->property; }
}

$pub  = new WithPublic( 'value' );

# Lets pretend it is held in a permanent cache:
$cache = serialize( $pub );

# Later on NEW code is deployed which change the property signature to private.
# Simulate the class changed:
$mut_pub_to_priv = unserialize(
	str_replace( '10:"WithPublic"', '11:"WithPrivate"', $cache ) );

var_dump( $mut_pub_to_priv );
# class WithPrivate#2 (2) {
#   private $property =>
#   NULL
#   public $property =>
#   string(5) "value"
# }

var_export( $mut_pub_to_priv->getProperty() );
# NULL

# The object restored from cache is not quite the one we expected and cause
# some havoc ( https://phabricator.wikimedia.org/T156364 ). Then Zend and HHVM
# consistently yield "NULL".

# The other way around. Cache with private property restore to class with
# public property


$priv = new WithPrivate( 'value' );
$cache = serialize( $priv );

$mut_priv_to_pub = unserialize(
	str_replace( '11:"WithPrivate"', '10:"WithPublic"', $cache) );

var_dump( $mut_priv_to_pub );
# class WithPublic#4 (2) {
#   public $property =>
#   NULL
#   private $property =>
#   string(5) "value"
# }

var_export( $mut_priv_to_pub->getProperty() );
# On Zend PHP: NULL
# On HHVM 3.15.4, 3.17.1: valueNULL

Output for 8.2.0 - 8.2.18, 8.3.0 - 8.3.4, 8.3.6: object(WithPrivate)#2 (1) { ["property":"WithPrivate":private]=> string(5) "value" } valueNULL Deprecated: Creation of dynamic property WithPublic::$property is deprecated in /in/TZk8B on line 49 object(WithPublic)#4 (2) { ["property"]=> NULL ["property":"WithPrivate":private]=> string(5) "value" } NULL
Output for 8.3.5: Warning: PHP Startup: Unable to load dynamic library 'sodium.so' (tried: /usr/lib/php/8.3.5/modules/sodium.so (libsodium.so.23: cannot open shared object file: No such file or directory), /usr/lib/php/8.3.5/modules/sodium.so.so (/usr/lib/php/8.3.5/modules/sodium.so.so: cannot open shared object file: No such file or directory)) in Unknown on line 0 object(WithPrivate)#2 (1) { ["property":"WithPrivate":private]=> string(5) "value" } valueNULL Deprecated: Creation of dynamic property WithPublic::$property is deprecated in /in/TZk8B on line 49 object(WithPublic)#4 (2) { ["property"]=> NULL ["property":"WithPrivate":private]=> string(5) "value" } NULL
Output for 7.2.8 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28: object(WithPrivate)#2 (1) { ["property":"WithPrivate":private]=> string(5) "value" } valueNULLobject(WithPublic)#4 (2) { ["property"]=> NULL ["property":"WithPrivate":private]=> string(5) "value" } NULL
Output for 7.2.0 - 7.2.7: object(WithPrivate)#2 (1) { ["property":"WithPrivate":private]=> string(5) "value" } valueNULLobject(WithPublic)#4 (1) { ["property"]=> string(5) "value" } valueNULL
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.33: object(WithPrivate)#2 (2) { ["property":"WithPrivate":private]=> NULL ["property"]=> string(5) "value" } NULLobject(WithPublic)#4 (2) { ["property"]=> NULL ["property":"WithPrivate":private]=> string(5) "value" } NULL

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