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Error Identifier: enum.duplicateConstant

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); // lint >= 8.1

enum Suit
{
	const JOKER = 'joker';
	const JOKER = 'jester';
}

Why is it reported? #

An enum (like a class) cannot declare two constants with the same name. PHP will produce a fatal error when it encounters a duplicate constant declaration. This applies to both regular class constants and enum case names sharing the same namespace within the enum.

How to fix it #

Remove the duplicate constant declaration or rename one of the constants:

 enum Suit
 {
 	const JOKER = 'joker';
-	const JOKER = 'jester';
+	const JESTER = 'jester';
 }

Non-ignorable error #

This error cannot be ignored using @phpstan-ignore or the ignoreErrors configuration. Non-ignorable errors indicate code that would cause a crash or a fatal error at runtime, or a fundamental problem in the analysed code that must be addressed.

Rules that report this error #

• PHPStan\Rules\Classes\DuplicateDeclarationRule [1]

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