Call parent magic method from override magic method in a trait

Question

Problem

I am open sourcing a trait which includes the magic method __call(). During testing, I encountered a challenge when the parent class of the class using the trait contains the __call method.

What I Tried

trait SomeTrait {
    public function __call($method, array $parameters) {
        // ...
        return parent::__call($method, $parameters);
    }
}

This results in the fatal error: Cannot access parent:: when current class scope has no parent

I also tried the following, based on some other answers:

return call_user_func_array([$this, '__call'], [$method, $parameters]);

This results in a Segmentation fault: 11. I imagine because of an infinite call loop.

Question

How can I invoke the parent's __call method from within the __call method of the trait?

If it is not possible from within the trait directly, how might I invoke the parent's __call method otherwise?

Answer 1

Please check code below:

trait SomeTrait
{
    public function __call($method, array $parameters)
    {
        // ...
        return is_callable(['parent', '__call']) ? parent::__call($method, $parameters) : null;
    }
}

class GreatParentClass
{
    public function __call($method, array $parameters)
    {
        return 'bar';
    }
}

class ParenClassWithoutCall
{

}

class ProxyClass extends GreatParentClass
{

}

class FooClass extends ProxyClass
{
    use SomeTrait;
}

class BarClass extends GreatParentClass
{
    use SomeTrait;
}

class BazClass extends ParenClassWithoutCall
{
    use SomeTrait;
}

class SomeClassWithoutParent
{
    use SomeTrait;
}

$class = new FooClass();
var_dump($class->foobar());

$class = new BarClass();
var_dump($class->foobar());

$class = new BazClass();
var_dump($class->foobar());

$class = new SomeClassWithoutParent();
var_dump($class->foobar());

This will print:

string(3) "bar"
string(3) "bar"
NULL
NULL

Sandbox with the code to check: http://3v4l.org/R8hI3

EDIT: I think this will cover all possibilities.