Getting errors about inferred and declared return types, but they don't make sense.

[ollieread]

I have the following method.

/**
 * @param E                               $element
 * @param \Smpl\Utils\Contracts\Predicate $filter
 * @return list<E>
 */
private function getElementsThatAre(mixed $element, Predicate $filter): array
{
    $elements = [];

    foreach ($this->elements as $existingElement) {
        $result = get_sign($this->getComparator()->compare($existingElement, $element));

        if ($filter($result)) {
            $elements[] = $existingElement;
        }
    }

    /** @infection-ignore-all */
    if (! empty($elements)) {
        usort($elements, $this->getComparator());
    }

    return $elements;
}

Which is causing the following error.

ERROR: MixedReturnTypeCoercion - src/Concerns/SortsCollection.php:284:16 - The declared return type 'list<int>' for Smpl\Collections\Concerns\SortsCollection::getElementsThatAre is more specific than the inferred return type 'list<(E:Smpl\Collections\Concerns\SortsCollection as mixed)|(E:Smpl\Collections\SortedQueue as mixed)>' (see https://psalm.dev/197)
     * @return list<E>

This method is not defined as returning list<int>, which appears nowhere in my codebase

[ollieread]

Hey @ollieread, can you reproduce the issue on https://psalm.dev ?

No, cannot recreate it.

[ollieread]

The trait that method is in, has the following class docblock.

/**
 * @template-covariant  I of mixed
 * @template            E of mixed
 *
 * @requires \Smpl\Collections\Contracts\SortedCollection<I, E>
 *
 * @mixin \Smpl\Collections\Contracts\Collection<I, E>
 */
trait SortsCollection {}

Everywhere that the trait is used, there's also this.

/** @use \Smpl\Collections\Concerns\SortsCollection<int, E> */
use SortsCollection;

It looks like it may, for some reason, be using I instead of E.

[ollieread]

I'm also having the following error with 5 other methods in this trait.

ERROR: MixedReturnTypeCoercion - src/Concerns/SortsCollection.php:178:16 - The declared return type 'int|null' for Smpl\Collections\Concerns\SortsCollection::lower is more specific than the inferred return type '(E:Smpl\Collections\SortedQueue as mixed)|null' (see https://psalm.dev/197)
     * @return E|null

[orklah]

Could you post the content of Collection and SortsCollection also? Or even better if you have the codebase available somewhere

[ollieread]

Could you post the content of Collection and SortsCollection also? Or even better if you have the codebase available somewhere

I've pushed all of my local changes (There were a lot) to a temporary branch called temporary-debug here: https://github.com/smplphp/collections/tree/temporary-debug

Here's SortsCollection https://github.com/smplphp/collections/blob/temporary-debug/src/Concerns/SortsCollection.php

And here's Collection https://github.com/smplphp/collections/blob/temporary-debug/src/Contracts/Collection.php

Let me know if you have any more specific questions, I'm aware that as far as small packages go, it isn't XD

[ollieread]

As a follow-up, the directory src/Concerns is ignored on that branch @orklah.

With the <directory> entry in psalm.xml, you get:

But without it, you get: