Error Identifier: mixin.internalInterface

← Back to mixin.*

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);

namespace Vendor {
	/** @internal */
	interface InternalInterface {
		public function doFoo(): void;
	}
}

namespace App {
	/** @mixin \Vendor\InternalInterface */
	class MyClass {}
}

Why is it reported? #

The @mixin PHPDoc tag references an interface that is marked as @internal. Internal interfaces are not part of the public API of the package that defines them. Referencing internal types in PHPDoc tags creates a dependency on implementation details that may change without notice in future versions of the package.

How to fix it #

Use a public (non-internal) interface or class provided by the package instead:

 namespace App {
-	/** @mixin \Vendor\InternalInterface */
+	/** @mixin \Vendor\PublicInterface */
 	class MyClass {}
 }

If no public alternative exists, remove the @mixin tag and implement the needed methods directly in the class.

How to ignore this error #

You can use the identifier mixin.internalInterface to ignore this error using a comment:

// @phpstan-ignore mixin.internalInterface
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: mixin.internalInterface

Rules that report this error #

• PHPStan\Rules\InternalTag\RestrictedInternalClassNameUsageExtension [1]