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Error Identifier: class.nameInUse

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 SomeNamespace;

use SomeOtherNamespace\Foo;

class Foo
{
}

Why is it reported? #

A class is being declared with a name that is already in use within the same namespace. This happens when a use statement imports a class with the same name as a class being declared in the current file. PHP cannot resolve which Foo is intended, resulting in a fatal error at runtime.

In the example above, Foo is imported via use SomeOtherNamespace\Foo and then a class named Foo is declared in the SomeNamespace namespace. Both refer to the short name Foo, creating a conflict.

How to fix it #

Rename the local class to avoid the conflict:

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

 use SomeOtherNamespace\Foo;

-class Foo
+class MyFoo
 {
 }

Or use an alias for the imported class:

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

-use SomeOtherNamespace\Foo;
+use SomeOtherNamespace\Foo as OtherFoo;

 class Foo
 {
 }

Or remove the use statement if the imported class is not needed:

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

-use SomeOtherNamespace\Foo;
-
 class Foo
 {
 }

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\Names\UsedNamesRule [1]

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