How to add static analysis to this tricky code?

[javaDeveloperKid]

This is very tricky for me. Could someone be so kind and help?
https://phpstan.org/r/11b388b4-0070-4a8c-a938-1c48cc208375

/**
 * @template T
 */
interface ItemsProvider
{

    /**
     * @return array<T>
     */
    public function getItems(): array;
}

class Executor
{
    public function execute(ItemsProvider $itemsProvider, callable $cb, array $cbArgs): void
    // or maybe should use this ...$cbArgs notation (forgot the this functionality name)?
    // public function execute(BatchItemsProviderInterface $subject, callable $cb, ...$cbArgs): void
    {
        foreach ($itemsProvider->getItems() as $item) {
            $cb($item, ...$cbArgs);
        }
    }
}

class FooDto {}

class SomeClass
{
    public function f()
    {
        /** @var ItemsProvider<FooDto> $itemsProvider */
        $itemsProvider = new class() implements ItemsProvider {
            public function getItems(): array {
                return [new FooDto, new FooDto];
            }
        };
        // HERE! How do I have it covered by PHPStan that doSth will be called with FooDto, x, y, z parameters respectively?
        (new Executor)->execute($itemsProvider, $this->doSth(...), ['x', 'y', 'z']);
        // or
        // (new Executor)->execute($itemsProvider, $this->doSth(...), 'x', 'y', 'z');
    }

    private function doSth(FooDto $fooDto, string $paramX, string $paramY, string $paramZ): void
    {
    }
}

[ondrejmirtes]

What's the expected output? What error do you want to report?

[javaDeveloperKid]

Hi. Don't look at the current errors in the playground. I've just copy-pasted the code sample there.
What I want to achieve is to backup this code with SA that makes sure that the arguments passed to Executor::execute() fulfill the SomeClass::doSth() signature.

[ondrejmirtes]

Yes, tell me what exact error message do you expect and why :)

[javaDeveloperKid]

Let's see:

function doSth(FooDto $fooDto, string $paramX, string $paramY, string $paramZ): void;

/** ItemsProvider<NotFooDto> $itemsProvider */
$itemsProvider;

// should report "Argument 1 passed to doSth should be of type FooDto, NotFooDto given"
// "Argument 2 passed to doSth should be of type string, int given"
(new Executor)->execute($itemsProvider, $this->doSth(...), [1, 'y', 'z']);
// or
// (new Executor)->execute($itemsProvider, $this->doSth(...), 1, 'y', 'z');

P.S. As said in the discussion, I wonder if the 3rd parameter in execute() should be array ...$cbArgs rather than array $cbArgs, i.e. what would PHPStan like more.

[ondrejmirtes]

You can achieve that with a custom rule that will check these calls. But personally I'd just do this:

    /**
     * @template T
     * @param ItemsProvider<T> $subject
     * @param callable(T): void $cb
     */
    public function execute(BatchItemsProviderInterface $subject, callable $cb): void
    {
        foreach ($itemsProvider->getItems() as $item) {
            $cb($item);
        }
    }

And call it like this:

(new Executor)->execute($itemsProvider, function (FooDto $item) {
    $this->doSth($item, 'x', 'y', 'z');
});

That's type safe with already present PHPStan capabilities.

[javaDeveloperKid]

That looks promising. I have to remind myself why I've written my signature instead of yours 🤔 Thank you Ondrej.