src/Selector/Key.php
public function equivalentTo(Expression $other)
    {
        if (!parent::equivalentTo($other)) {
            return false;
        }

        /* @var static $other */
        return $this->key === $other->key;
    }
public function equivalentTo(Expression $other)
    {
        if (!parent::equivalentTo($other)) {
            return false;
        }

        /* @var static $other */
        return $this->key === $other->key;
    }
{@inheritdoc}