Bug report

When creating a first class callable, I'm getting the error "Creating callable from a non-native method" (callable.nonNativeMethod) even when the code is protected by a call to method_exists() or is_callable().

The idea is that a base class that is meant to be extended has a method that creates a callable out of a target method that an extending class may or may not define. The base class uses a method_exists() (or is_callable()) guard to ensure that the callable is only generated when the extending class actually defines the target method. However, PHPStan still reports the error.

https://3v4l.org/imBZu

class BaseClass
{
    public function getCallable() : ?Closure {
        // This works fine, but PHPStan reports callable.nonNativeMethod error.
        return method_exists($this, 'myCallable') ? $this->myCallable(...) : null;
    }
}

class ChildOne extends BaseClass
{
    //
}

class ChildTwo extends BaseClass
{
    public function myCallable() : string {
        return 'I exist on child two.';
    }
}

Code snippet that reproduces the problem

https://phpstan.org/r/7ddd69de-cc28-4038-963c-0f04bda2b00e

Expected output

Expect no errors when callable generation is guarded.

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