New comments reported for previously read ones [#14426]

I've noticed this on the drupal.org site for a while, and it recently started appearing on a couple of my sites. The recent overhaul of the comment.module and specifically comment statistics, may have indirectly addressed this problem, but I thought I'd report it just in case. Sorry if it is no longer relevant or if it is a duplicate.

Basically the comment links reports new comments even when previously read. Easiest place to see this is the user profile -> track listing of recent posts. Old posts will occasionally appear as having new posts when no new posts have been made. For example there was a node which I posted a single comment on. Sometime later it was reported as having 1 new comment, however the only comment available was the one I posted. Perhaps this is related to http://drupal.org/node/13984

Comments

Comment #1

moshe weitzman commented 20 December 2004 at 21:12

we throw out read/unread history after 30 days or so. i don't know the exact number. this is done in order to optimize all those red stars you know and love. as you can imagine, maintaining read/unread status on every node for every user for ever is not such a good idea. in the past, our queries sufferred because of this.

Comment #2

dtan commented 24 December 2004 at 09:17

Right. . .keeping a limited history is acceptable, but the behaviour is probably not the desired one. IMO it would make more sense not to display any 'new comments' for comments which were added before that history period.

function comment_num_new($nid, $timestamp = 0) {
  global $user;

  if ($user->uid) {
    // Retrieve the timestamp at which the current user last viewed the
    // specified node.
    if (!$timestamp) {
      $timestamp = node_last_viewed($nid);
    }

    // Use the timestamp to retrieve the number of new comments.
    $result = db_result(db_query('SELECT COUNT(c.cid) FROM {node} n INNER JOIN {comments} c ON n.nid = c.nid WHERE n.nid = %d AND timestamp > %d AND c.status = 0', $nid, $timestamp));

    return $result;
  }
  else {
    return 0;
  }

}

Perhaps I am misreading the code, but it appears as though if a node has not been viewed before ( either brand new or there is no history ), then the comment count would return all of the comments for that node. This is inconsistentent with viewing the actual node as no comments are actually marked as new. The theme_comments_view uses the node_is_new which uses the history limit.