src/Type/Definition/ObjectType.php
public function isTypeOf($value, $context, ResolveInfo $info)
    {
        return isset($this->config['isTypeOf']) ? call_user_func(
            $this->config['isTypeOf'],
            $value,
            $context,
            $info
        ) : null;
    }
public function isTypeOf($value, $context, ResolveInfo $info)
    {
        return isset($this->config['isTypeOf']) ? call_user_func(
            $this->config['isTypeOf'],
            $value,
            $context,
            $info
        ) : null;
    }
@param mixed[]      $value
@param mixed[]|null $context

@return bool|null