I was about to merge 2 duplicated items in Wikidata, but I accidentally merged the wrong one (Q9143779 and Q4702008). I have undone the merge on Q4702008, however when I clicked undo on the changes on Q9143779, I got the error
Internal error [WbugggpAMEwAAFUt4DkAAAAQ] 2017-09-15 09:42:26: Fatal exception of type "Diff\Patcher\PatcherException"
And when I clicked restore on the last good revision, I got
Undo failed Invalid content data Return to Wikidata:Main Page.
clicking restore on the last good version takes me to https://www.wikidata.org/w/index.php?title=Q9143779&action=edit&restore=198877769 , and clicking Save also results in Invalid content data for me too.
The page https://pl.wikipedia.org/wiki/Akwanga_(meteoryt) is unlinked.
I just did another restore of a bad merge, and it failed with Invalid content data
https://www.wikidata.org/w/index.php?title=Q19281208&action=edit&restore=309323077
Rolling back the merge still works, apparently, and afterwards it’s also possible to restore the old version. I used this on Q38906046 (rollback diff), and @MisterSynergy also had success with this on Q34836264 (rollback diff).
I dont have rollback it seems.
I now have rollback, and can confirm it is a workaround for some of the merges. Thanks for finding that!
OTOH, it isnt useful for some of the merges I have to undo, because the editor made many good edits before doing a merge.
Is somebody able to provide a full stacktrace for one of the error messages mentioned above?
/srv/mediawiki/php-1.30.0-wmf.18/extensions/Wikidata/extensions/Wikibase/repo/includes/Actions/EditEntityAction.php(314): Wikibase\EntityContent->getPatchedCopy(Wikibase\Repo\Content\EntityContentDiff)
#1 /srv/mediawiki/php-1.30.0-wmf.18/extensions/Wikidata/extensions/Wikibase/repo/includes/Actions/EditEntityAction.php(260): Wikibase\EditEntityAction->showUndoForm()
#2 /srv/mediawiki/php-1.30.0-wmf.18/includes/MediaWiki.php(499): Wikibase\EditEntityAction->show()
#3 /srv/mediawiki/php-1.30.0-wmf.18/includes/MediaWiki.php(293): MediaWiki->performAction(Article, Title)
#4 /srv/mediawiki/php-1.30.0-wmf.18/includes/MediaWiki.php(848): MediaWiki->performRequest()
#5 /srv/mediawiki/php-1.30.0-wmf.18/includes/MediaWiki.php(523): MediaWiki->main()
#6 /srv/mediawiki/php-1.30.0-wmf.18/index.php(43): MediaWiki->run()
#7 /srv/mediawiki/w/index.php(3): include(string)
#8 {main}Diff\Patcher\PatcherException from line 587 of /srv/mediawiki/php-1.30.0-wmf.18/extensions/Wikidata/extensions/Wikibase/repo/includes/Content/EntityContent.php: EntityContent must not contain Entity data as well as a redirect after applying the patch!
I only see three hits in the past 24 hours, not sure if that's the error users are seeing or not.
Change 378934 had a related patch set uploaded (by Thiemo Mättig (WMDE); owner: Thiemo Mättig (WMDE)):
[mediawiki/extensions/Wikibase@master] Fix undoing merge operations that turned Items into a redirects
I was able to reproduce this quite easily by merging two items, and the trying to undo (not revert) the last edit that turned the first item into a redirect. This fails much, much more often now because https://gerrit.wikimedia.org/r/377298 removed an optimization. No test properly covered this.
Change 378934 merged by jenkins-bot:
[mediawiki/extensions/Wikibase@master] Fix undoing merge operations that turned Items into a redirects
Change 378954 had a related patch set uploaded (by Ladsgroup; owner: Thiemo Mättig (WMDE)):
[mediawiki/extensions/Wikibase@wmf/1.30.0-wmf.19] Fix undoing merge operations that turned Items into a redirects
Change 378955 had a related patch set uploaded (by Ladsgroup; owner: Thiemo Mättig (WMDE)):
[mediawiki/extensions/Wikibase@wmf/1.30.0-wmf.18] Fix undoing merge operations that turned Items into a redirects
Change 378960 had a related patch set uploaded (by Ladsgroup; owner: Amir Sarabadani):
[mediawiki/extensions/Wikidata@wmf/1.30.0-wmf.18] Fix undoing merge operations that turned Items into a redirects
Change 378961 had a related patch set uploaded (by Ladsgroup; owner: Amir Sarabadani):
[mediawiki/extensions/Wikidata@wmf/1.30.0-wmf.19] Fix undoing merge operations that turned Items into a redirects
Change 378954 merged by jenkins-bot:
[mediawiki/extensions/Wikibase@wmf/1.30.0-wmf.19] Fix undoing merge operations that turned Items into a redirects
Change 378955 merged by jenkins-bot:
[mediawiki/extensions/Wikibase@wmf/1.30.0-wmf.18] Fix undoing merge operations that turned Items into a redirects
Change 378961 merged by jenkins-bot:
[mediawiki/extensions/Wikidata@wmf/1.30.0-wmf.19] Fix undoing merge operations that turned Items into a redirects
Change 378960 merged by jenkins-bot:
[mediawiki/extensions/Wikidata@wmf/1.30.0-wmf.18] Fix undoing merge operations that turned Items into a redirects
Mentioned in SAL (#wikimedia-operations) [2017-09-19T18:07:03Z] <ladsgroup@tin> Synchronized php-1.30.0-wmf.19/extensions/Wikidata/extensions/Wikibase/repo/includes/Content/EntityContent.php: Fix undoing merge operations that turned Items into a redirects, part I (T175984) (duration: 00m 50s)
Mentioned in SAL (#wikimedia-operations) [2017-09-19T18:08:27Z] <ladsgroup@tin> Synchronized php-1.30.0-wmf.19/extensions/Wikidata/extensions/Wikibase/repo/tests/phpunit/includes/Content/EntityContentTest.php: Fix undoing merge operations that turned Items into a redirects, part II (T175984) (duration: 00m 50s)
Mentioned in SAL (#wikimedia-operations) [2017-09-19T18:15:37Z] <ladsgroup@tin> Synchronized php-1.30.0-wmf.18/extensions/Wikidata/extensions/Wikibase/repo/includes/Content/EntityContent.php: Fix undoing merge operations that turned Items into a redirects, part I (T175984) (duration: 00m 49s)
Mentioned in SAL (#wikimedia-operations) [2017-09-19T18:17:02Z] <ladsgroup@tin> Synchronized php-1.30.0-wmf.18/extensions/Wikidata/extensions/Wikibase/repo/tests/phpunit/includes/Content/EntityContentTest.php: Fix undoing merge operations that turned Items into a redirects, part II (T175984) (duration: 00m 48s)
Okay, the deploy is done and I tested and it worked, I call this resolved, feel free to reopen if the problem persists.