Bug report

When passing variables with types narrowed using conditionals to an anonymous function with the use keyword, there seems to be some loss of type information, making the type inside the function more broad than outside the scope.

This does not happen with arrow functions, which likely are treated differently, given how they also bind variables in a different manner.

Code snippet that reproduces the problem

https://phpstan.org/r/73f07010-4dee-4c3c-ac35-7dc5a29c6e9a

<?php declare(strict_types = 1);

interface HasFoo
{
    public function foo(): int;
}

interface HasBar
{
    public function bar(): int;
}

class HelloWorld
{
    /**
     * @param  "foo"|"bar"  $method
     * @param  ($method is "foo" ? HasFoo : HasBar)  $a
     * @param  ($method is "foo" ? HasFoo : HasBar)  $b
     */    
    public function add(string $method, HasFoo|HasBar $a, HasFoo|HasBar $b): void
    {
        $add = $a->{$method}() + $b->{$method}();
        $addInArrow = fn () => $a->{$method}() + $b->{$method}();
        $addInAnonymous = function () use ($a, $b, $method): int {
            return $a->{$method}() + $b->{$method}(); // this suddenly no longer knows about the relation between $method and $a/$b types
        };
    }
}

Expected output

All three cases to be considered equivalent and not reporting any errors.

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