How to resolve static analysis error for QueryAdapter/AdapterInterface

[mustanggb]

I am doing:

  use Pagerfanta\Doctrine\MongoDBODM\QueryAdapter;
  use Pagerfanta\Pagerfanta;

  $adapter = new QueryAdapter($queryBuilder);
  $pagerfanta = Pagerfanta::createForCurrentPageWithMaxPerPage($adapter, $currentPage, $maxPerPage);

Which gives the static analysis error:

ERROR: MixedArgumentTypeCoercion - Argument 1 of Pagerfanta\Pagerfanta::createForCurrentPageWithMaxPerPage expects
Pagerfanta\Adapter\AdapterInterface<Pagerfanta\T>, but parent type Pagerfanta\Doctrine\MongoDBODM\QueryAdapter<mixed>
provided

So I tried to make it happy with:

  use Pagerfanta\Doctrine\MongoDBODM\QueryAdapter;
  use Pagerfanta\Pagerfanta;

+ /** @var \Pagerfanta\Adapter\AdapterInterface<\Pagerfanta\T> */
  $adapter = new QueryAdapter($queryBuilder);
  $pagerfanta = Pagerfanta::createForCurrentPageWithMaxPerPage($adapter, $currentPage, $maxPerPage);

But now it says:

ERROR: UndefinedDocblockClass - Docblock-defined class, interface or enum named Pagerfanta\T does not exist

Does anyone know the proper way to do this?

[mbabker]

T is just a placeholder for a generic type, not an actual class name.

/** @var QueryAdapter<mixed> **/
$adapter = new QueryAdapter($queryBuilder);

That should be the minimum OK annotation to provide a generic type. If your SA is groaning about the use of mixed, then change it to whatever result type your query is providing (I'm assuming this would be a mapped document in the ODM, so say you're querying the list of users, that would be /** @var QueryAdapter<\App\Document\User> **/).

[mustanggb]

Brilliant, thanks for the speedy reply.

/** @var QueryAdapter<mixed> */ works, and doesn't complain about being mixed.

However /** @var QueryAdapter<\App\Document\User> */ gives the error:

ERROR: InvalidArgument - Argument 1 of Pagerfanta\Pagerfanta::createForCurrentPageWithMaxPerPage expects
Pagerfanta\Adapter\AdapterInterface<Pagerfanta\T>, but Pagerfanta\Doctrine\MongoDBODM\QueryAdapter<App\Document\User> provided

I can go with mixed for now, but if there are any ideas as to why specifying the actual type has complaints I'd welcome the knowledge.

[mbabker]

Maybe the generic type's not being inferred from the adapter?

/** @var Pagerfanta<\App\Document\User> **/
$pagerfanta = Pagerfanta::createForCurrentPageWithMaxPerPage($adapter, $currentPage, $maxPerPage);

I can't say I'm a big Psalm user so I don't know if there's just something here that Psalm tries that PHPStan doesn't or if I've just never done anything to hit this particular SA issue before.

Also, if there are ways to improve the static analysis here, pull requests are highly welcome as I know I definitely don't get these generics/templates right more often than not 😅

[mustanggb]

if there are ways to improve the static analysis here, pull requests are highly welcome

Hmm, it might be the case.

This works without error:

  /** @var QueryAdapter<User> */
  $adapter = new QueryAdapter($queryBuilder);
  /** @var Pagerfanta<User> */
  $pagerfanta = new Pagerfanta($adapter);

But as mentioned previously, this gives an error:

  /** @var QueryAdapter<User> */
  $adapter = new QueryAdapter($queryBuilder);
  /** @var Pagerfanta<User> */
  $pagerfanta = Pagerfanta::createForCurrentPageWithMaxPerPage($adapter, $currentPage, $maxPerPage);

However, with the following change the error goes away:

  /**
   * @template T
   *
   * @implements PagerfantaInterface<T>
   */
  class Pagerfanta implements PagerfantaInterface, \JsonSerializable
  {
      /**
       * @param AdapterInterface<T> $adapter
       */
      public function __construct(
          private readonly AdapterInterface $adapter,
      ) {}
  
      /**
-      * @param AdapterInterface<T> $adapter
+      * @param AdapterInterface $adapter
       *
       * @return self<T>
       */
      public static function createForCurrentPageWithMaxPerPage(AdapterInterface $adapter, int $currentPage, int $maxPerPage): self
      {
          $pagerfanta = new self($adapter);
          $pagerfanta->setMaxPerPage($maxPerPage);
          $pagerfanta->setCurrentPage($currentPage);
  
          return $pagerfanta;
      }
  }

Does that seem a reasonable change to you?

I've recreated the issue at: https://psalm.dev/r/f6d313f1ba
Which suggests @param AdapterInterface<T> $adapter is perhaps not correct for createForCurrentPageWithMaxPerPage()?

[mustanggb]

Okay, might have found the answer, Psalm doesn't like templates being used in static functions: vimeo/psalm#7507 (comment)

So should be able to fix it with something like:

      /**
       * @param AdapterInterface<T> $adapter
+      * @psalm-param AdapterInterface<mixed> $adapter
       *
       * @return self<T>
       */
      public static function createForCurrentPageWithMaxPerPage(AdapterInterface $adapter, int $currentPage, int $maxPerPage): self
      {
          $pagerfanta = new self($adapter);
          $pagerfanta->setMaxPerPage($maxPerPage);
          $pagerfanta->setCurrentPage($currentPage);
  
          return $pagerfanta;
      }

If it's okay I created a pull request: BabDev/Pagerfanta#54