1.2.809. No Magic Method With Array

Magic method __set() doesn’t work for array syntax.

When overloading properties, they can only be used for scalar values, excluding arrays. Under the hood, PHP uses __get() to reach for the name of the property, and doesn’t recognize the following index as an array. It yields an error : “Indirect modification of overloaded property”.

It is possible to use the array syntax with a magic property : by making the __get returns an array, the syntax will actually extract the expected item in the array.

This is not reported by linting.

In this analysis, only properties that are found to be magic are reported. For example, using the b property outside the class scope is not reported, as it would yield too many false-positives.

<?php

class c {
    private $a;
    private $o = array();

    function __get($name) {
        return $this->o[$name];
    }

    function foo() {
        // property b doesn't exists
        $this->b['a'] = 3;

        print_r($this);
    }

    // This method has no impact on the issue
    function __set($name, $value) {
        $this->o[$name] = $value;
    }
}

$c = new c();
$c->foo();

?>

See also Overload.

1.2.809.1. Suggestions

• Use a distinct method to append a new value to that property

• Assign the whole array, and not just one of its elements

1.2.809.2. Specs

Short name	Classes/NoMagicWithArray
Rulesets	All, Analyze, CE, CI-checks, Changed Behavior, LintButWontExec
Exakat since	0.12.4
PHP Version	All
Severity	Major
Time To Fix	Slow (1 hour)
Precision	Medium
Features	magic-method
Note	This issue may lint but will not run
Available in	Entreprise Edition, Community Edition, Exakat Cloud