Reply-to address may be invalid

I have found with Messaging 6.x-2.x and 6.x-4.x, if you use PHPMailer the reply-to address is not set properly. There is a fix for this. I'm not sure it would work with 7.x

If you use PHPMailer, rather than Drupal Mail to send messages you must fix a bug in the messaging_phpmailer.module file to ensure that the reply-to address is set properly in outgoing. Find the following code:

if (!empty($replyto['name']) && !empty($replyto['email'])) {
  $mail->AddReplyTo($replyto['email'], $replyto['name']);
  }

Replace it with:

if(!empty($message['headers']['Reply-To'])) {
    $mail->AddReplyTo($message['headers']['Reply-To']);
  }

You're correct, it is a regression. All I can tell you is that it works and the change to preg_match does not work on 3 sites I have. These sites use messaging 6.x-4.x-dev. I can't explain why this is so.

I am using the phpmailer 5.1 library if that is helpful.

I was getting the wrong 'reply-to' - it was defaulting to the 'from' but only for some emails.

More weirdly, if I only sent to some of my subscribers it was ok, but if I sent to all of them, the reply-to would be wrong.
But inconsistently - I had 2 admin users subscribing to check - sometimes one, the other, both, none would have the wrong reply-to.

So I added a line at the end to hard code the reply-to, hence ignoring any if statements wrapped around it earlier on (see bottom of this post)
This works, but not ideal - do you think some of those if conditions need to be reviewed?
Why do we need these conditions? If any fail then quite a few steps won't be done

if ($params ----------------------- OK, so what is the problem if no params?
&& ($reply = variable_get('mailcomment_mailbox', '')) -------------- why do we need this if we set reply-to in the UI?
&& user_access('post comments', $account) ---------------------- doesn't Mailhandler and feeds already do this?
&& (node_load($event->objects['node']->value)->comment == 2) ---- OK I guess just checking that comments are open

function mailcomment_notifications_notifications_message_alter(&$message) {
    $params = array();
    // For now, just for non digested emails
    if (($account = current($message->get_destinations())->get_user()) && $message->digest == FALSE && $message->send_method()->type == 'mail') {
        $event = current($message->events);
        if (($event->type == 'node-post' || $event->type == 'node-comment') && !empty($event->objects['node'])) {
            $node = node_load($event->objects['node']->value);
            $params['uid'] = $node->uid;
            $params['nid'] = $node->nid;
            $params['cid'] = 0;
            $params['time'] = $node->created;
            if ($event->action == 'comment' && !empty($event->objects['comment'])) {
                $comment = comment_load($event->objects['comment']->value);
                $params['uid'] = $comment->uid;
                $params['cid'] = $comment->cid;
                $ancestor_msg_id = mailcomment_mail_comment_ancestor_message_id($params['nid'], $params['cid']);
                $params['time'] = $comment->created;
            }
        }
    }
    // If we've got some params out of the message, embed them into the message id for emails only
    // and only if the recipient of the message is allowed to post comments.
if ($params && ($reply = variable_get('mailcomment_mailbox', '')) && user_access('post comments', $account) && (node_load($event->objects['node']->value)->comment == 2)) {
        // Alter message subjects
        if (variable_get('mailcomment_alter_subjects', 1)) {
            $subject = $message->get_template()->get_element('subject');
            if (($event->type == 'node' || $event->type == 'node-comment') && !empty($event->objects['node'])) {
                $subject['#markup'] = variable_get('site_name', '') ? '[' . variable_get('site_name', '') . '] ' . node_load($event->objects['node']->value)->title : $subject['#markup'];
            }
            if ($event->action == 'comment') {
                $subject['#markup'] = t('Re:') . ' ' . $subject['#markup'];
            }
            $message->subject = $subject;
        }

        $message->params['mail']['headers']['Message-ID'] = mailcomment_build_messageid($params);
        $message->params['mail']['headers']['Reply-To'] = $reply;
        if (isset($ancestor_msg_id)) {
            $message->params['mail']['headers']['In-Reply-To'] = $ancestor_msg_id;
        }
        // Add marker text into the message header part taking care of already existing text
        $insert_reply_text = variable_get('mailcomment_insert_reply_text', 1);
        $text = variable_get('mailcomment_reply_text', t('((( Reply ABOVE this LINE to POST a COMMENT )))'));
        if ($text && $insert_reply_text) {
            $prefix = array($text);
            $header = $message->get_template()->get_element('header');
            $prefix[] = $header['#markup'];
            $header['#markup'] = implode("\n", $prefix);
            $message->get_template()->add_element('header', $header);
        }
        // Alter $params in order to provide recipient uid in message signature
        $params['uid'] = $account->uid;
        $footer = $message->get_template()->get_element('footer');
        //$footer['mailcomment'] = array('#type' => 'messaging_link', '#text' => 'View original post: ', '#url' =>  url('mailcomment/redirect/' . mailcomment_build_messageid($params), array('absolute' => TRUE)));
        $message->get_template()->add_element('footer', $footer);
    }
  $message->params['mail']['headers']['Reply-To'] = 'myhardcodedemailaddress@mydomain.com';
}

UPDATE - ok the hard coding works, but I've noticed a couple of other issues:

• the 'reply line' was also missing - I now realise that the emails with the wrong reply-to also have missing reply-line
• this leads me to believe that even in the same notification run, the module isn't taking effect for some emails
• I can't isolate which conditions are not being met as it's not the same user recipient or sender or even the same mail
• it's something to do with the combination of factors together which result in some notifications bypassing function mailcomment_notifications_notifications_message_alter

Another thing I noticed in the code is different event types -should they be the same? First line uses 'node-post'

if (($event->type == 'node-post' || $event->type == 'node-comment') && !empty($event->objects['node'])) 
 

Then later it uses 'node'

if (($event->type == 'node' || $event->type == 'node-comment') && !empty($event->objects['node']))