OMG: Gerrit is very buggy since the recent major updates

We've recently upgraded Gerrit through a few major versions, which has some important user-facing changes:

• Prolog is being deprecated in favour of a custom DSL (see also b/195)

• Gerrit now stores the state of labels on a CL explicitly somewhere, instead of computing it on the fly

• We had to switch to a different owners plugin due to some ... compat issues? (cl/6685)

• Other stuff, lukegb probably knows more details.

Related CLs to this are e.g. cl/6505, cl/6660, cl/6665, cl/6685

As a result of this, we now have a variety of bugs in Gerrit that didn't exist before, for example:

• Score copying randomly doesn't work, leading to situations where people e.g. change a commit message and lose Verified+1 (with no way to get it back, since there is no build to re-run for that patchset!) (e.g. cl/6948)

• Gerrit state gets out of sync with reality, e.g. in the overview the columns of label states don't reflect reality anymore

• Maybe issues with gerrit-queue have gotten worse? It's hard to tell

• There are random UI bugs where certain buttons don't work, or state switches around in strange ways

• Owners plugin seems to be broken on some users (e.g. in cl/6685 we never got all approvals to work, and it seemed to be an issue with users like e.g. qyliss, who has a different username configured, and the new owners plugin having a custom patch to make usernames work at all)

This list is inexhaustive, it's just noticeable in everyday flows that Gerrit is now kind of wonky.

I'm not sure what to do about this at the moment, filing issue for tracking and discussion.

1. Another one:

   • Gerrit will randomly mark commits in a chain as "Ready to submit" when they are not. Clicking the Submit button then causes an error.

   tazjin at 2022-10-16T10·14+00

2. Score copying randomly doesn't work, leading to situations where people e.g. change a commit message and lose Verified+1 (with no way to get it back, since there is no build to re-run for that patchset!) (e.g. cl/6948)

   Happened with https://cl.tvl.fyi/c/depot/+/7053/2 as well.

   flokli at 2022-10-21T16·25+00

3. I think some of the problems have been resolved:

   • Change indexing should work again, mostly, after cl/7172
   • Gerrit bump to the 3.7.0 RC has pulled in https://gerrit-review.googlesource.com/337968 which should fix vote copying - basically the problem was that the vote copying would happen, THEN CI would vote on a previous version, which wouldn't get copied forward.

   lukegb at 2022-11-06T16·57+00