Merge when pipeline succeeds still set after resolving conflicts

Summary

In some weird sequences, MWPS can remain set and the MR stays unmerged even when the pipeline has successfully run. Weird, I know!

Steps to reproduce

  1. Create an MR.
  2. Set it to MWPS.
  3. Pipeline starts running.
  4. Create an unresolved discussion thread.
  5. Pipeline complete successfully.
  6. Resolve discussion thread.

At this point the MR is unmerged, set to MWPS, and the pipeline has already successfully completed.

The work around is to unset MWPS and then Merge.

Example Project

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What is the current bug behavior?

(What actually happens)

What is the expected correct behavior?

When discussions are resolved, the code should figure out whether MWPS is set and if the pipeline has already completed successfully it should unset MWPS and display the regular "Merge" button.

Relevant logs and/or screenshots

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Output of checks

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Results of GitLab environment info

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sudo gitlab-rake gitlab:env:info)


(For installations from source run and paste the output of:
sudo -u git -H bundle exec rake gitlab:env:info RAILS_ENV=production)

Results of GitLab application Check

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(For installations with omnibus-gitlab package run and paste the output of:
sudo gitlab-rake gitlab:check SANITIZE=true)


(For installations from source run and paste the output of:
sudo -u git -H bundle exec rake gitlab:check RAILS_ENV=production SANITIZE=true)


(we will only investigate if the tests are passing)

Possible fixes

(If you can, link to the line of code that might be responsible for the problem)