← Back to assert.*

Error Identifier: assert.internalInterface

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);

// In package vendor/some-library:

namespace SomeLibrary;

/** @internal */
interface Logger
{
	public function log(string $message): void;
}

<?php declare(strict_types = 1);

// In your code:

namespace App;

use SomeLibrary\Logger;

class Checker
{
	/**
	 * @phpstan-assert Logger $value
	 */
	public function assertLogger(mixed $value): void
	{
		// ...
	}
}

Why is it reported? #

A @phpstan-assert PHPDoc tag references an interface that is marked as @internal. Internal types are not meant to be used outside of the package or namespace where they are defined. Depending on internal types in your assertions creates a fragile dependency on implementation details that can change without notice.

In the example above, the @phpstan-assert Logger $value tag references the internal Logger interface from SomeLibrary.

How to fix it #

Use a public (non-internal) type in the @phpstan-assert tag instead. If you need to assert against similar functionality, check whether the library provides a public interface, or define your own type:

 <?php declare(strict_types = 1);
 
 namespace App;

-use SomeLibrary\Logger;
+use Psr\Log\LoggerInterface;

 class Checker
 {
 	/**
-	 * @phpstan-assert Logger $value
+	 * @phpstan-assert LoggerInterface $value
 	 */
-	public function assertLogger(mixed $value): void
+	public function assertLoggerInterface(mixed $value): void
 	{
 		// ...
 	}
 }

How to ignore this error #

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

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

Rules that report this error #

• PHPStan\Rules\InternalTag\RestrictedInternalClassNameUsageExtension [1]

Edit this page on GitHub