Error Identifier: mul.rightNonNumeric

← Back to mul.*

Every error reported by PHPStan has an error identifier. Here’s a list of all error identifiers. In PHPStan Pro you can see the error identifier next to each error and filter errors by their identifiers.

Code example #

<?php declare(strict_types = 1);

function multiply(int $a, bool $flag): int
{
	return $a * $flag;
}

Why is it reported? #

This rule is part of phpstan-strict-rules.

The right operand of the multiplication operator (*) is not a numeric type. PHP will attempt to cast non-numeric values to numbers, which can lead to unexpected results or warnings. Strict rules require that only numeric types are used in arithmetic operations.

How to fix it #

Ensure the operand is a numeric type:

-function multiply(int $a, bool $flag): int
+function multiply(int $a, int $b): int
 {
-	return $a * $flag;
+	return $a * $b;
 }

Or explicitly cast the value:

 function multiply(int $a, bool $flag): int
 {
-	return $a * $flag;
+	return $a * (int) $flag;
 }

How to ignore this error #

You can use the identifier mul.rightNonNumeric to ignore this error using a comment:

// @phpstan-ignore mul.rightNonNumeric
codeThatProducesTheError();

You can also use only the identifier key to ignore all errors of the same type in your configuration file in the ignoreErrors parameter:

parameters:
	ignoreErrors:
		-
			identifier: mul.rightNonNumeric

Rules that report this error #

• PHPStan\Rules\Operators\OperandsInArithmeticMultiplicationRule [1] phpstan/phpstan-strict-rules