The sorry tale of our article List of The Adventures of Tintin characters is an object lesson in what happens when articles are moved and merged thoughtlessly.
We begin with one article, A:
- 18 May 2008: Minor characters in The Adventures of Tintin was cut-and-paste moved, becoming X, Characters in The Adventures of Tintin.
- 15 July 2009: Characters in The Adventures of Tintin was moved to Characters of The Adventures of Tintin.
Meanwhile, at another article, Y:
- 4 October 2008: List of The Adventures of Tintin characters was moved to List of characters in The Adventures of Tintin.
Where it all went wrong was when the articles were history merged, despite having completely incompatible histories. This appears to have been a misunderstanding of a requested content merge for the two articles.
- 7 October 2009: Characters of The Adventures of Tintin was merged over List of characters in The Adventures of Tintin.
Finally, the resulting chimera article, Z, was moved again... to the same name one of its precursors had only a year and a half earlier.
- 10 March 2010: List of characters in The Adventures of Tintin was moved to List of The Adventures of Tintin characters.
I fixed the situation. It required this:
Ouch.
Here's what that diagram represents:
- deleted Z and restored only the post-merge revisions, which in reality only represented the continuation of X
- moved those to a subpage of the talk page
- restored the mixed-up merged revisions
- moved those to another subpage as a workspace
- moved the earlier subpage back to being Z so it could continue being read and/or edited
- deleted the workspace subpage
- identified the revisions from X (thankfully, a significant difference in size allowed them to be identified easily) and restored them
- moved the resulting subpage to a new subpage name
- deleted Z again
- moved the X subpage to Z
- restored the later revisions of Z, thus joining the two histories
- restored the leftover revisions in the workspace, thus resurrecting Y
- deleted the redirect at the former title of Y
- moved Y to its original location
- restored the Y redirect, merging its history with that of the Y page
- deleted the redirect at the original location of X
- restored the revisions prior to the c&p move
- deleted Z yet again
- moved A to Z
- restored the later revisions of A, the redirect
- restored Z, thus merging its history with that it was cut from.
I even left out some steps here. I also performed selective delete/restores in order to not include the revisions showing me moving the article parts around. Worse still, at the end MediaWiki simply failed to perform a restoration of the complete Z (T45911), requiring me to restore half of the ~1100 revisions at a time. That was annoying. MediaWiki needs to provide a much better mechanism for performing these sorts of procedures (T23312).