Low quality post reviews and deleted posts

Question

The timeline for this post is intriguing:

Note that this was deleted by Glen and myself and a mod, then undeleted by the mod (not sure why - not an issue here) and then it was actually deleted through the low quality post review queue (I might have seen that once before).

The review for this that actually triggered the delete is #76538

Note that Glen and I both partook in that review. The six delete or recommend deletion on the post is what actually completed that review.

The post (10k link) now looks like:

The (possible) bugs exhibited here:

• Deleting (or undeleting) a post does not complete (or restart from fresh?) a LQP review that hasn't been completed.
• The 'deleted by' shows the first round of deletion, rather than the final deleted by however a review should show up.

Related (but not a dup): Low Quality post shows as "Review completed" with all "Delete" votes, but it's not deleted?

Answer 1

Related to #1:

Post deletion never completes a review, it invalidates a review. That process can take up to 15 minutes to occur, though, because the review item doesn't get officially invalidated immediately, but whenever the queue itself gets updated again. While in a deletion state, it is not further reviewable - as in the item won't be served to reviewers anymore while it's pending invalidation. But if the post gets quickly undeleted before the system can invalidate the task, the review item can continue on and remain active as if nothing ever happened, allowing further actions of any kind.

If the item does get invalidated, though, it does not resume if the post eventually gets undeleted. If it ever qualifies for review again (which is possible depending on which queue it was in), a new review task will be created for it.

Related to #2:

This is a very long-standing bug that pops up in many forms. When posts get deleted by review, no users get attached to the post deletion, so any users who were in there from a previous deletion will still be present. Likely the code looks for those users to be populated before anything else and, if they are, displays the users rather than looking for what the most recent deletion actually was.