Check release sometime fails to find remote ref

[brichet]

Description

Sometime the prep-git action fails with an error relative to the remote ref, for example in jupyterlab/jupyter-collaboration#378:

fatal: couldn't find remote ref refs/pull/378/merge.

The workaround is to close the PR and open a new one.

Error log

Initialized empty Git repository in /home/runner/work/jupyter-collaboration/jupyter-collaboration/.jupyter_releaser_checkout/.git/
fatal: couldn't find remote ref refs/pull/378/merge
Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.11.10/x64/bin/jupyter-releaser", line 8, in 
    sys.exit(main())
             ^^^^^^
  File "/opt/hostedtoolcache/Python/3.11.10/x64/lib/python3.11/site-packages/click/core.py", line 1157, in __call__
    return self.main(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/hostedtoolcache/Python/3.11.10/x64/lib/python3.11/site-packages/click/core.py", line 1078, in main
    rv = self.invoke(ctx)
         ^^^^^^^^^^^^^^^^
  File "/home/runner/work/_actions/jupyter-server/jupyter_releaser/v2/jupyter_releaser/cli.py", line 121, in invoke
    super().invoke(ctx)
  File "/opt/hostedtoolcache/Python/3.11.10/x64/lib/python3.11/site-packages/click/core.py", line 1688, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/hostedtoolcache/Python/3.11.10/x64/lib/python3.11/site-packages/click/core.py", line 1434, in invoke
    return ctx.invoke(self.callback, **ctx.params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/hostedtoolcache/Python/3.11.10/x64/lib/python3.11/site-packages/click/core.py", line 783, in invoke
    return __callback(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/runner/work/_actions/jupyter-server/jupyter_releaser/v2/jupyter_releaser/cli.py", line 367, in prep_git
    lib.prep_git(ref, branch, repo, auth, username, git_url)
  File "/home/runner/work/_actions/jupyter-server/jupyter_releaser/v2/jupyter_releaser/lib.py", line 537, in prep_git
    util.run(f"{util.GIT_FETCH_CMD} +{ref}:{ref_alias}")
  File "/home/runner/work/_actions/jupyter-server/jupyter_releaser/v2/jupyter_releaser/util.py", line 94, in run
    raise e
  File "/home/runner/work/_actions/jupyter-server/jupyter_releaser/v2/jupyter_releaser/util.py", line 86, in run
    process = tee(cmd, **kwargs)
              ^^^^^^^^^^^^^^^^^^
  File "/home/runner/work/_actions/jupyter-server/jupyter_releaser/v2/jupyter_releaser/tee.py", line 159, in run
    raise subprocess.CalledProcessError(
subprocess.CalledProcessError: Command 'git fetch origin --filter=blob:none --quiet +refs/pull/378/merge:refs/pull/378/merge' returned non-zero exit status 128.
Traceback (most recent call last):
  File "", line 198, in _run_module_as_main
  File "", line 88, in _run_code
  File "/home/runner/work/_actions/jupyter-server/jupyter_releaser/v2/jupyter_releaser/actions/prep_release.py", line 11, in 
    run_action("jupyter-releaser prep-git")
  File "/home/runner/work/_actions/jupyter-server/jupyter_releaser/v2/jupyter_releaser/actions/common.py", line 25, in run_action
    _run(target, *args, **kwargs)
  File "/home/runner/work/_actions/jupyter-server/jupyter_releaser/v2/jupyter_releaser/util.py", line 94, in run
    raise e
  File "/home/runner/work/_actions/jupyter-server/jupyter_releaser/v2/jupyter_releaser/util.py", line 86, in run
    process = tee(cmd, **kwargs)
              ^^^^^^^^^^^^^^^^^^
  File "/home/runner/work/_actions/jupyter-server/jupyter_releaser/v2/jupyter_releaser/tee.py", line 159, in run
    raise subprocess.CalledProcessError(
subprocess.CalledProcessError: Command 'jupyter-releaser prep-git' returned non-zero exit status 1.

Reproduce

This seems to be random, so difficult to reproduce.

Context

• Widget to display users of a collaborative document jupyterlab/jupyter-collaboration#378
• Use filepath relative to repo root jupyterlite/litegitpuller#22
• Upload to current working directory jupyterlite/litegitpuller#23

[krassowski]

I was under impression that this happens when closing and reopening some PRs.

[jtpio]

I was under impression that this happens when closing and reopening some PRs.

That's what we often do on the JupyterLab repo after a Galata snapshot update, but not sure to have seen on https://github.com/jupyterlab/jupyterlab yet?

[krassowski]

It did pop up a couple of times, here for example: jupyterlab/jupyterlab#16866. The workaround I was using was to merge with main branch.

[krassowski]

It started appearing a month ago or so, I think this was a change in GitHub API behaviour.

[jtpio]

Good to know. I wonder if there is something we can do in the releaser to handle this new behavior.

[brichet]

I was under impression that this happens when closing and reopening some PRs.

I hadn't noticed it.

The workaround I was using was to merge with main branch.

Thanks, this is a better workaround than closing the PR, as long as it is not handled in the releaser.

[krassowski]

This is because when you close and re-open the PR the merge refs (refs/pull/*/merge) are deleted not regenerated until a new commit is pushed.

This was reported to GitHub on https://github.com/orgs/community/discussions/142978.

If GitHub is not going to fix this behaviour we could instead checkout the PR branch, check out the merge target and perform the merge manually, something along the lines of (I did not test that):

git fetch origin ${{ github.event.pull_request.base.ref }}:${{ github.event.pull_request.base.ref }}
git fetch origin ${{ github.event.pull_request.head.ref }}:${{ github.event.pull_request.head.ref }}
git checkout ${{ github.event.pull_request.base.ref }}
git merge --no-ff --no-commit ${{ github.event.pull_request.head.ref }}