Support `__invoke` methods

[darthf1]

Hi!

Thanks a lot for this great phpstan plugin, i was able to cleanup a lot of stuff in my repository.

I would like to be able to mark certain classes as not used, or skip marking certain classes as used, when certain conditions apply.

<?php

final readonly class MyDomainEvent {};
final readonly class MyDomainEvent2 {};

final readonly class MyDomainEventHandler()
{
  public function __invoke(MyDomainEvent $event): void
  {}
}

public function doSomething(): void
{
    $this->raise(new MyDomainEvent()); // class is used inside the raise method call, and inside the invoke method call inside the event handler
    $this->raise(new MyDomainEvent2()); // class is only used inside the raise method call
}

Specifically, I want to mark domain events which are raised (through ->raise(...)) but not handled through an event handler, as unused. Or, i dont want to count the "raise" method as usage for any event class.

I tried overriding the getUsages for this but i dont have any luck so far. Since there is only the MemberUsageProvider interface, this was the only location i could think of to do this.

Question: is the above do-able with the current way things work with dead-code-detector?

[darthf1]

Ah, i dont know why i didnt see https://github.com/shipmonk-rnd/dead-code-detector?tab=readme-ov-file#excluding-usages before.

final class EventRaisingUsageExcluder implements MemberUsageExcluder
{
    public function shouldExclude(ClassMemberUsage $usage, Node $node, Scope $scope): bool
    {
        $origin = $usage->getOrigin();

        return $origin->getMethodName() === 'raise';
    }

    public function getIdentifier(): string
    {
        return 'raise_exclude';
    }
}

I guess something like this, but this doesnt work. Ill continue to investigate on my end :)

[janedbal]

Sadly, __invoke methods are not yet supported. So this is currently impossible to do.

[janedbal]

In order to support __invoke tracking without false-positives, we would need to:

• Support all native functions that cause implicit __invoke calls (e.g. array_map]
• Most probably mark __invoke as used when such class is passed to some vendor code (as we cannot track if it really gets called there or not)
• Support direct calls $object()
• ...