generics.notSupportedBound

Code example

<?php declare(strict_types = 1);

/**
 * @template T of resource
 */
class ResourceWrapper
{
}

Why is it reported?

The @template tag specifies a bound type that is not supported as a generic type constraint. PHPStan supports the following types as template bounds: mixed, object, class/interface types (including generic classes), array, string, int, float, bool, null, union types, intersection types, iterable, key-of, object-shape, and other template types.

Types like resource, callable, void, and never are not supported as template bounds.

How to fix it

Use a supported type as the bound. If the template type does not need a specific bound, omit the of clause entirely:

 <?php declare(strict_types = 1);

 /**
- * @template T of resource
+ * @template T
  */
 class ResourceWrapper
 {
 }

Or use a more appropriate supported bound type:

 <?php declare(strict_types = 1);

 /**
- * @template T of resource
+ * @template T of object
  */
 class ResourceWrapper
 {
 }