phpspec-contains-instance-matcher

<?php

class SomethingSpec extends ObjectBehavior
{
    function it_contains_an_instance_of(Class $object)
    {
        $this->getArray()->shouldContainAnInstanceOf($object);
    }
    
    public function getMatchers()
    {
        return [
            'containAnInstanceOf' => function($subject, $instance) {
                return is_array($subject) && false !== array_walk($instance, $subject);
            }
        ];
    }
}