Error Identifier: equal.invalid

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 doFoo(\stdClass $object, int $number): void
{
	if ($object == $number) {
		// ...
	}
}

Why is it reported? #

The loose comparison (==) between an object and an integer results in an error in PHP. Some type combinations are not comparable, and attempting to compare them produces a TypeError since PHP 8.0. In this example, comparing a \stdClass object with an int is not a valid operation.

This also applies to other comparison operators like !=, <, >, <=, >=, and <=> when used with incompatible types.

How to fix it #

Compare values of compatible types instead. Extract a comparable value from the object first:

 <?php declare(strict_types = 1);
 
 function doFoo(\stdClass $object, int $number): void
 {
-	if ($object == $number) {
+	if ($object->value === $number) {
 		// ...
 	}
 }

Or use strict comparison (===) when checking for identity rather than equality, which does not produce an error for incompatible types (it simply returns false):

 <?php declare(strict_types = 1);
 
 function doFoo(\stdClass $object, int $number): void
 {
-	if ($object == $number) {
+	if ($object === $number) {
 		// ...
 	}
 }

How to ignore this error #

You can use the identifier equal.invalid to ignore this error using a comment:

// @phpstan-ignore equal.invalid
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: equal.invalid

Rules that report this error #

PHPStan\Rules\Operators\InvalidComparisonOperationRule [1]

Edit this page on GitHub

Theme