app/code/community/Adyen/Payment/Helper/Data.php
public function isOpenInvoice($paymentMethod)
    {
        if ($this->isKlarna($paymentMethod) ||
            strcmp($paymentMethod, self::RATEPAY) === 0 ||
            $this->isAfterPay($paymentMethod)) {
            return true;
        }

        return false;
    }
public function isOpenInvoice($paymentMethod)
    {
        if ($this->isKlarna($paymentMethod) ||
            strcmp($paymentMethod, self::RATEPAY) === 0 ||
            $this->isAfterPay($paymentMethod)) {
            return true;
        }

        return false;
    }
public function isOpenInvoice ( $ paymentMethod ) { if ( $ this -> isKlarna ( $ paymentMethod ) || strcmp ( $ paymentMethod , self :: RATEPAY ) === 0 || $ this -> isAfterPay ( $ paymentMethod ) ) { return true ; } return false ; }
Identifiy if payment method is an openinvoice payment method

@param $paymentMethod
@return bool
Identifiy if payment method is an openinvoice payment method