empty() returns true for magic method __get() results

[hibipo-ro]

Description

Description

The empty() function returns true when called on a property accessed through the __get() magic method, even though the property contains a non-empty value.

Expected Behavior

empty($accessor->name) should return false because the property contains the string "Tokyo".

Actual Behavior

empty($accessor->name) returns true, which is unexpected.

Code to Reproduce

<?php

class Accessor
{
    public function __construct(public $target) {}
    
    public function __get($key)
    {
        return $this->target->$key;
    }
}

$school = new stdClass();
$school->name = "Tokyo";

$accessor = new Accessor($school);
var_dump($accessor->name); // "Tokyo"
var_dump(strcmp($accessor->name, $accessor->target->name)); // 0
var_dump($accessor->name === $accessor->target->name); // true

var_dump(empty($accessor->name)); // true - WHY?
var_dump(empty($accessor->target->name)); // false

$name = $accessor->name;
var_dump(empty($name)); // false

Tested on

• PHP 8.1
• PHP 8.2
• PHP 8.3

PHP Version

PHP 8.2.28 (cli) (built: May 21 2025 23:17:46) (NTS)
Copyright (c) The PHP Group
Zend Engine v4.2.28, Copyright (c) Zend Technologies
    with Xdebug v3.4.3, Copyright (c) 2002-2025, by Derick Rethans

Operating System

No response

[MorganLOCode]

Generally when you're using the overloading functions like __get, you'll want to do something about the rest. In this case, empty() checks to see if $accessor->name is set or not (which it isn't, because Accessor doesn't have a property called name). Unset properties are considered empty.

To quote the linked page:

__isset() is triggered by calling isset() or empty() on inaccessible (protected or private) or non-existing properties.

You'd be wanting to implement Accessor::__isset() as well to handle such tests.

[nielsdos]

Well explained and correct. Thanks for replying!
Closing as per previous comment.