Last modified: 2013-03-06 17:04:36 UTC

Wikimedia Bugzilla is closed!

Wikimedia migrated from Bugzilla to Phabricator. Bug reports are handled in Wikimedia Phabricator.
This static website is read-only and for historical purposes. It is not possible to log in and except for displaying bug reports and their history, links might be broken. See T46360, the corresponding Phabricator task for complete and up-to-date bug report information.
Bug 44360 - Edit conflict handling is broken on Wikimedia wikis
Edit conflict handling is broken on Wikimedia wikis
Status: RESOLVED DUPLICATE of bug 21494
Product: Wikimedia
Classification: Unclassified
General/Unknown (Other open bugs)
wmf-deployment
All All
: High major (vote)
: ---
Assigned To: Nobody - You can work on this!
:
Depends on:
Blocks:
  Show dependency treegraph
 
Reported: 2013-01-25 22:22 UTC by MZMcBride
Modified: 2013-03-06 17:04 UTC (History)
5 users (show)

See Also:
Web browser: ---
Mobile Platform: ---
Assignee Huggle Beta Tester: ---


Attachments

Description MZMcBride 2013-01-25 22:22:35 UTC
Edit conflict handling is quite simply broken on Wikimedia wikis. I've hit a number of edit conflicts in the past week or so, and the "Stored text" and the text in the top textarea is simply wrong. So if you try to submit with it, you overwrite someone else's edit silently. This should be easy to reproduce.
Comment 1 Andre Klapper 2013-01-25 23:31:23 UTC
On a number of wikis, or en.wikipedia.org? 
Any specific example / screenshot / testcase?

This reminded me of bug 41280... Tentatively moving to ContentHandler component.
Comment 2 MZMcBride 2013-01-25 23:32:35 UTC
I've only experienced the issue on the English Wikipedia.
Comment 3 MZMcBride 2013-01-26 00:11:57 UTC
There are various reports of users hitting outdated page histories on the English Wikipedia's technical village pump. I wonder if something similar is going on here.

I tried to reproduce this bug on test.wikipedia.org and en.wikipedia.org and wasn't able to. :-/
Comment 4 Andre Klapper 2013-01-26 00:26:01 UTC
On en.wp:VP I see many mentions that link to https://en.wikipedia.org/wiki/Wikipedia:Village_pump_%28technical%29#Users_reporting_site_time_issues_and_delay_in_visible_update_of_edits which I so far didn't understand as an editing issue but an issue with serving outdated content on the mainpage.
Comment 5 Aude 2013-01-26 02:42:11 UTC
hmm.... the phpunit tests pass for me (on the deployment branch and master).  I am not sure what's going on, but can try to reproduce.
Comment 6 Aude 2013-01-26 02:43:31 UTC
the EditPage phpunit tests pass, which test edit conflicts
Comment 7 MZMcBride 2013-01-26 06:56:04 UTC
Throwing this back to Wikimedia, as I don't think it's ContentHandler-related. Also lowering the priority, since it doesn't seem like it's getting reported a lot right now. It's an annoying bug, but it doesn't seem pervasive. I'll try to take a screenshot the next time I encounter the problem.
Comment 8 Andre Klapper 2013-01-26 20:01:20 UTC
Leslie has commented in http://en.wikipedia.org/wiki/Village_pump_%28technical%29#Users_reporting_site_time_issues_and_delay_in_visible_update_of_edits

In short: Likely multicast forwarding router bug, and she is investigating.

Related: bug 44391 - "old revisions of pages are shown when not logged in and also revision history is outdated".
Comment 9 Nemo 2013-01-28 08:23:22 UTC
This bug is a mess. Last comments should have been on bug 44360.
As for the edit conflicts, WORKSFORME. Please reopen if there are specific examples or steps to reproduce.
Comment 10 MZMcBride 2013-01-28 22:23:09 UTC
(In reply to comment #9)
> This bug is a mess. Last comments should have been on bug 44360.

This appears to be a typo, as this is bug 44360.

> As for the edit conflicts, WORKSFORME. Please reopen if there are specific
> examples or steps to reproduce.

Specific examples:

* https://en.wikipedia.org/w/index.php?title=Wikipedia:Requests_for_comment/Article_feedback&diff=prev&oldid=534372779

* https://en.wikipedia.org/w/index.php?title=Wikipedia:Requests_for_comment/Article_feedback&diff=prev&oldid=534738771

In both of these cases, I hit an edit conflict, I copied and pasted just my text from the second (lower) textarea, and then when I submitted my edit, I somehow silently overwrote other users' edits.
Comment 11 Nemo 2013-01-28 22:30:42 UTC
(In reply to comment #10)
> (In reply to comment #9)
> > This bug is a mess. Last comments should have been on bug 44360.
> 
> This appears to be a typo, as this is bug 44360.

Sure, I meant bug 44391.

> Specific examples:
> 
> *
> https://en.wikipedia.org/w/index.php?title=Wikipedia:Requests_for_comment/
> Article_feedback&diff=prev&oldid=534372779
> 
> *
> https://en.wikipedia.org/w/index.php?title=Wikipedia:Requests_for_comment/
> Article_feedback&diff=prev&oldid=534738771
> 
> In both of these cases, I hit an edit conflict, I copied and pasted just my
> text from the second (lower) textarea, and then when I submitted my edit, I
> somehow silently overwrote other users' edits.

Thanks. The two examples are a bit different.
In the first it's about two different sections: were you section-editing just the first of the two? Probably originally you were, but then had an edit conflict with the 19:59 comment, and ended up saving the full text of the page after the 20:03 comment? If you re-did a section edit and removed something on another section, this would be a bug (it sometimes happened in the past).
In the second, it's just a normal double edit conflict. I'm not sure how smart the edit conflict detection is supposed to be here, maybe it could get smarter (and this would be a feature request); surely it's better to check the diff before saving after a conflict, as usual.
Comment 12 MZMcBride 2013-02-11 11:28:23 UTC
It seems to have happened again in this edit:

https://en.wikipedia.org/w/index.php?title=Wikipedia:In_the_news/Candidates&diff=537690318&oldid=537690261
Comment 13 Nemo 2013-02-11 11:30:04 UTC
(In reply to comment #12)
> It seems to have happened again in this edit:
> 
> https://en.wikipedia.org/w/index.php?title=Wikipedia:In_the_news/
> Candidates&diff=537690318&oldid=537690261

How do you know? Did the user say what they did? It's hard to guess from the diff only. Thanks.
Comment 14 MZMcBride 2013-02-12 02:14:26 UTC
(In reply to comment #13)
> How do you know? Did the user say what they did? It's hard to guess from the
> diff only.

I hit the same issue as described in comment 0 during this period of intense editing. It's some kind of nasty race condition, I think.

That diff shows that the user accidentally overwriting another user's edit. I think it's safe to assume this overwrite was unintentional.
Comment 15 Nemo 2013-02-12 06:49:45 UTC
(In reply to comment #14) 
> I hit the same issue as described in comment 0 during this period of intense
> editing. It's some kind of nasty race condition, I think.

Without asking the user it's impossible to tell. Maybe the "your text" below was just blindly copied to the edit area. There are too many ways to produce a diff like that.

> 
> That diff shows that the user accidentally overwriting another user's edit. I
> think it's safe to assume this overwrite was unintentional.

Sure, we can mourn and pray together, but without specific information nothing can be understood or done.
Comment 16 MZMcBride 2013-03-06 00:53:01 UTC
https://en.wikipedia.org/w/index.php?title=User_talk:MZMcBride&diff=542292244&oldid=542292175

Presumably another instance of whatever this issue is.
Comment 17 Nemo 2013-03-06 09:31:05 UTC

*** This bug has been marked as a duplicate of bug 21494 ***

Note You need to log in before you can comment on or make changes to this bug.


Navigation
Links