Gerrit

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What steps will reproduce the problem?
1. Mark a change work in progress
2. Search for that change or search for all wip changes with 'is:wip'
3. Notice that the WIP change is unconditionally marked as Merge Conflicted in the listing

What is the expected output?

The change should only be marked as merge conflict if there is an actual merge conflict.

What do you see instead?

All WIP changes are marked merge conflict.

Please provide any additional information below.

We see this behavior running Gerrit 3.5.2-35-g04be0ba23b-dirty with change.mergeabilityComputationBehavior = API_REF_UPDATED_AND_CHANGE_REINDEX set. I am not sure if we had this same problem under 3.4 as well.

Digging into rest API responses and the code a bit I think I see why this is happening but don't yet understand the root cause. It seems that every wip change's json data has mergeable:false and work_in_progress:true set. Then https://gerrit.googlesource.com/gerrit/+/refs/tags/v3.5.2/polygerrit-ui/app/utils/change-util.ts#160 is able to set both merge conflict and wip statuses as they are not part of the same if else if block but are checked separately. This code doesn't appear to have been updated recently.

I suspect the problem is that mergeable:false should be mergeable:null. This is based on isMergeable's behavior here: https://gerrit.googlesource.com/gerrit/+/refs/tags/v3.5.2/java/com/google/gerrit/server/query/change/ChangeData.java#1050. In that location we check if mergeable is null then we check if the change is a work in progress, if so we return null.

That implies mergeable is already true when calling isMergeable here: https://gerrit.googlesource.com/gerrit/+/refs/tags/v3.5.2/java/com/google/gerrit/server/change/ChangeJson.java#623. It seems the only location we call setMergeable with a non null value is : https://gerrit.googlesource.com/gerrit/+/refs/tags/v3.5.2/java/com/google/gerrit/server/index/change/ChangeField.java#802. Should this index query be updated to check if the change is a wip before setting the value? Or perhaps we should check if a work in progress in isMergeable and short circuit with null there?

I'm not entirely sure how this is all tied together yet so neither approach may be appropriate.