Tickets: Trying to modify deleted comment crashes cryptically (“TypeError: unsubscriptable object”)

[Jun Omae]

How to reproduce

1. Create a new ticket
2. Add a comment to it
3. In a browser/tab A, show the comment’s "Edit" form
4. From another browser/tab, remove the comment
5. From browser/tab A, submit the updated comment

The issue occurs with both 0.12-stable and 1.0-stable.

2014-09-16 12:15:40,582 Trac[main] ERROR: Internal Server Error:
Traceback (most recent call last):
  File "/src/tracdev/git/trac/web/main.py", line 529, in _dispatch_request
    dispatcher.dispatch(req)
  File "/src/tracdev/git/trac/web/main.py", line 243, in dispatch
    resp = chosen_handler.process_request(req)
  File "/src/tracdev/git/trac/ticket/web_ui.py", line 174, in process_request
    return self._process_ticket_request(req)
  File "/src/tracdev/git/trac/ticket/web_ui.py", line 499, in _process_ticket_request
    ticket.modify_comment(change['date'], req.authname, comment)
TypeError: unsubscriptable object

[Christian Boos]

Maybe too "corner-case" of a problem to be worth fixing on 0.12-stable. I'd suggest moving it on 1.0.3.

[Ryan J Ollos]

Retargeting tickets in milestone:1.0.3 that have no owner. Please retarget as appropriate.

[Ryan J Ollos]

Moved ticket assigned to next-stable-1.0.x since maintenance of 1.0.x is coming to a close. Please move the ticket back if it's critical to fix on 1.0.x.

[Ryan J Ollos]

Milestone renamed

[Philippe Cloutier <chealer@…>]

Thanks for reporting

Obviously, ideally:

1. Tab B would warn that the comment is being modified.
2. If deletion proceeds anyway, tab A would be notified as soon as the comment is deleted.

That being said, if this still occurs, I am not sure what is the best approach. Are all comments versioned (except for spam explicitly purged)? If so, should the deletion be deleted, or should a recreation entry be added? If not, should a purged comment be restored with its initial timestamp, or treated as a new comment? And if restoring, what should notifications say?

This comment is from Philippe "Chealer" Cloutier. All of my comments and contributions in this ticket are offered under the terms of CC0 1.0 (unless otherwise noted).

[Jun Omae]

It is a duplicate of #12623 which has been fixed in [15263] (Trac 1.0.14).