I have a couple of repositories hosted on bit bucket with wikis. Here is an example: https://bitbucket.org/runhello/jumpcore/wiki/Home Up until a few minutes ago, the wiki for this site was public editable-- any bitbucket account could edit it.
A few minutes ago, a spammer created a junk page (they have also been hitting my issues and bitbucket technical support is already assisting me) named "(Delaware) (((1800+[snip])) QuickBooks Pro Support Phone Number .md" on the wiki. I quickly noticed, deleted their page and turned off public edits.
However because of this i noticed something. Their edits are forever in my wiki edit history. If I check out the hg backed repository, I can see in
hg glog --style=compact:
@ 38[tip] 283c3d2d2c61 2016-04-22 21:13 +0000 runhello <REDACTED> | Removed files via bitbucket | o 37 7fb6101a5bc1 2016-04-22 21:11 +0000 makbaldwin1 <firstname.lastname@example.org> | Edited online | o 36 6fda7925433a 2014-10-06 15:34 +0000 runhello <REDACTED> | Edited online
makbaldwin1 edit is the bad one. I can still see its full contents using hg.
Because this is only one commit with one page, and it is just spam, this is not harmful. However I think this shows a feature limitation you should fix. Imagine: What if the edit had been harmful, for example posting someone's personal information? Then I would be stuck hosting that edit in the history of my bitbucket site forever. Or what if instead of one commit, it had been 400? Then the usefulness of my wiki would be restricted, because I would have to deal with those 400 commits every time I tried to edit my wiki using the mercurial interface.
A thing I notice: If this were a git repository and the wiki were backed by git, I could delete history from the wiki using
git push -f. Similarly, if this were a source repository instead of a wiki-repository I could delete history in an emergency using the "strip changeset" feature. The "strip changeset" feature does not work for the wiki.
I think "strip changeset" should be available for hg-backed wikis.