Term changes in issue not being properly displayed in emails

Ultimately, the reason that this bug is showing up is that in comment_alter_taxonomy_project_issue_metadata(), for the case where $op == 'diff', we have this code:

      $old_terms = _comment_alter_taxonomy_build_term_list($node, $old_data);
      $new_terms = _comment_alter_taxonomy_build_term_list($node, $new_data);

Within _comment_alter_taxonomy_build_term_list(), there is this code:

  else {
    $cid = isset($comment->cid) ? $comment->cid : 0;
    $result = db_query(db_rewrite_sql('SELECT cat.tid, t.* FROM {comment_alter_taxonomy} cat LEFT JOIN {term_data} t ON cat.tid = t.tid LEFT JOIN {vocabulary} v ON t.vid = v.vid WHERE cat.nid = %d AND cat.cid = %d ORDER BY v.weight, t.weight, t.name', 't', 'tid'), $node->nid, $cid);
    while ($term = db_fetch_object($result)) {
      $term_list[$term->tid] = $term;
    }

So, when the project issue module is processing the original issue node, comment_alter_taxonomy_project_issue_metadata() effectively tells project_issue that there were no changes in terms for the issue, which is technically true, and so project issue doesn't print any terms that were added to the issue when the original issue was created.

The Issue tags terms are displayed in the metadata table at the top of all issue nodes on the web page because within project_issue_view() comment_alter_taxonomy_project_issue_metadata() is called with $op == 'current'. However, when project_issue is sending out emails of issues, it doesn't do the same thing, because for issue emails we don't always want to show all of the metadata for an issue and we want to point out changes in things like status, priority, etc. within the "table" at the top of the email.

So to actually fix this problem I think we'd need to rewrite some of the code in project issue that generates this table at the top of the email, probably so that it behaves more similarly to how the code executed when viewing the node behaves.