Support/EventListener/TicketEventListener.php
protected function updateNumber(TicketInterface $ticket)
    {
        if (0 == strlen($ticket->getNumber())) {
            $this->numberGenerator->generate($ticket);

            return true;
        }

        return false;
    }
protected function updateNumber(TicketInterface $ticket)
    {
        if (0 == strlen($ticket->getNumber())) {
            $this->numberGenerator->generate($ticket);

            return true;
        }

        return false;
    }
Updates the number.

@param TicketInterface $ticket

@return bool Whether the sale number has been update.