private function setDueDate(Carbon $dueDate = null)
    {
        if (is_null($dueDate)) {
            $dueDate = Carbon::now();
        }

        $this->dueDate = $dueDate;
    }
private function setDueDate(Carbon $dueDate = null)
    {
        if (is_null($dueDate)) {
            $dueDate = Carbon::now();
        }

        $this->dueDate = $dueDate;
    }
private function setDueDate ( Carbon $ dueDate = null ) { if ( is_null ( $ dueDate ) ) { $ dueDate = Carbon :: now ( ) ; } $ this -> dueDate = $ dueDate ; }
Set the due date of the invoice, if null, set the current date.

@param Carbon $dueDate | null

@return void
Set the due date of the invoice if null set the current date .