generics.noParent

Code example

<?php declare(strict_types = 1);

/**
 * @template T
 * @template U of \Exception
 */
class Collection
{
}

/**
 * @extends Collection<int, \InvalidArgumentException>
 */
class FooDoesNotExtendAnything
{
}

Why is it reported?

The class has an @extends PHPDoc tag specifying generic type arguments for Collection, but it does not actually extend any class. The @extends tag is meaningless without a corresponding extends clause in the class declaration.

The same applies to @implements tags on classes that do not implement the referenced interface, and @use tags on classes that do not use the referenced trait.

How to fix it

Add the missing extends clause:

 /**
  * @extends Collection<int, \InvalidArgumentException>
  */
-class FooDoesNotExtendAnything
+class FooDoesNotExtendAnything extends Collection
 {
 }

Or remove the unnecessary @extends tag if the class is not supposed to extend Collection:

-/**
- * @extends Collection<int, \InvalidArgumentException>
- */
 class FooDoesNotExtendAnything
 {
 }