1.2.1459. __toString() Throws Exception

Magical method __toString() can’t throw exceptions.

In fact, __toString() may not let an exception pass. If it throw an exception, but must catch it. If an underlying method throws an exception, it must be caught.

A fatal error is displayed, when an exception is not intercepted in the __toString() function.

<?php

class myString {
    private $string = null;

    public function __construct($string) {
        $this->string = $string;
    }

    public function __toString() {
        // Do not throw exceptions in __toString
        if (!is_string($this->string)) {
            throw new Exception("$this->string is not a string!!");
        }

        return $this->string;
    }
}

?>

See also __toString().

1.2.1459.1. Suggestions

• Remove any usage of exception from __toString() magic method

1.2.1459.2. Specs

Short name	Structures/toStringThrowsException
Rulesets	All, Analyze, Changed Behavior
Exakat since	0.8.4
PHP Version	With PHP 7.4 and older
Severity	Major
Time To Fix	Quick (30 mins)
Precision	Very high
Features	exception, magic-method
Available in	Entreprise Edition, Exakat Cloud