With admin level RevisionDelete now viewable and not the same as suppression in practice, we're seeing revisions with a wide range of combinations of delete/restore and RevDelete activity.
A major problem has come to light. The differences in how deleted and undeleted revisions are referenced, discussed in bug 18104, are causing RevisionDelete to break badly all over the place. Examples:
- Links in the suppression log often now error out. For example in my suppression 00:21 October 25 2009 (and several following it), "change visibility" now clicks through to non-working links. the links that once worked, no longer work, presumably since the revision(s) have since been deleted/undeleted.
- Diffs no longer show page history properly. Revisions exist where something's missing in history but it's not clear what. For example the first suppression on the deleted article [[Chris Fournier]], by IP user 126.96.36.199. Clicking "diff" on this revision shows a diff that appears to delete data but not add any new data (nothing on right hand side), and a revision text that includes clear defamatory material that (apparently) was neither introduced in that diff, nor existed in the previous revision.
- Revisions that were moved from "normal" to "deleted" after some RevDelete actions and before others, change their designation from "revision" to "archive" or something. RevDelete logs and page history becomes very hard to follow as the links fail and as revisions are split between multiple pages and sections within pages.
Sorry to throw this at the developers, but this is a ghastly mess; it's getting hard to track down what happened when something comes up on a wiki.
I think trying to keep two parallel schemes for "deleted revisions" and "all other revisions" is to blame.
The solution seems to be to ensure deleted revisions can also be looked up (and DIFFed) by their original revision_id even after deletion, which would mean RevisionDelete and other functionality wouldn't have to account for a possible change of reference id at some future time.
Suggestion for fixing:
- Ensure that revision_id's will transparently link through to the correct deleted revision if the revision is deleted, preventing breakage of links when a revision is deleted or restored. This allows revisions to be referenced by one fixed identifier in RevisionDelete regardless of later deletion/restoration.
- Modify RevDel and all functions that add page information to the logs, so that all links related to a revision are referenced by the revision's revision_id alone, whether or not the revision is deleted.
A big job but it's got to the point that we need revisions accessible via the same reference id (possibly keeping timestamp as a 2nd identifier for ease and compatibility) whether they are deleted or not.