prepare-upload-args does not handle error when remote branch cannot be fast-forwarded

[Athos Ribeiro]

When a branch changes locally, trying to use prepare-upload args crashes if a previous upload was performed using the same branch name.

While this is expected in most cases, it may be an issue when sponsoring uploads since the git-ubuntu user (i.e., the uploader) will not interact directly with their own remote/branch.

We could improve the experience here by providing a better error message or asking if the user want to retry with a force push.

$ dpkg-buildpackage -S -nc -v27.13.6 $(git ubuntu prepare-upload args)
To ssh://git.launchpad.net/~athos-ribeiro/ubuntu/+source/ubuntu-advantage-tools
 ! [rejected] upload-27.14.4-jammy -> upload-27.14.4-jammy (non-fast-forward)
error: failed to push some refs to 'ssh://<email address hidden>/~athos-ribeiro/ubuntu/+source/ubuntu-advantage-tools'
hint: Updates were rejected because the tip of your current branch is behind
hint: its remote counterpart. Integrate the remote changes (e.g.
hint: 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.
04/06/2023 11:19:41 - ERROR:Command exited 1: git push athos-ribeiro refs/heads/upload-27.14.4-jammy:refs/heads/upload-27.14.4-jammy
04/06/2023 11:19:41 - ERROR:stdout: [Not captured]

04/06/2023 11:19:41 - ERROR:stderr: [Not captured]

Traceback (most recent call last):
  File "/snap/git-ubuntu/1175/usr/bin/git-ubuntu", line 11, in <module>
    load_entry_point('gitubuntu==1.0', 'console_scripts', 'git-ubuntu')()
  File "/snap/git-ubuntu/1175/usr/lib/python3/dist-packages/gitubuntu/__main__.py", line 270, in main
    sys.exit(args.func(args))
  File "/snap/git-ubuntu/1175/usr/lib/python3/dist-packages/gitubuntu/prepare_upload.py", line 170, in cli_printargs
    headers = push(
  File "/snap/git-ubuntu/1175/usr/lib/python3/dist-packages/gitubuntu/prepare_upload.py", line 125, in push
    repo.git_run(
  File "/snap/git-ubuntu/1175/usr/lib/python3/dist-packages/gitubuntu/git_repository.py", line 1841, in git_run
    return git_run(
  File "/snap/git-ubuntu/1175/usr/lib/python3/dist-packages/gitubuntu/git_repository.py", line 267, in git_run
    return run(['git'] + list(args), env=env, **kwargs)
  File "/snap/git-ubuntu/1175/usr/lib/python3/dist-packages/gitubuntu/run.py", line 87, in run
    raise e
  File "/snap/git-ubuntu/1175/usr/lib/python3/dist-packages/gitubuntu/run.py", line 64, in run
    cp = subprocess.run(
  File "/snap/git-ubuntu/1175/usr/lib/python3.8/subprocess.py", line 516, in run
    raise CalledProcessError(retcode, process.args,
subprocess.CalledProcessError: Command '['git', 'push', 'athos-ribeiro', 'refs/heads/upload-27.14.4-jammy:refs/heads/upload-27.14.4-jammy']' returned non-zero exit status 1.
dpkg-buildpackage: info: source package ubuntu-advantage-tools
dpkg-buildpackage: info: source version 27.14.4~22.04
dpkg-buildpackage: info: source distribution jammy
dpkg-buildpackage: info: source changed by Renan Rodrigo <email address hidden>
 dpkg-source --before-build .
dpkg-buildpackage: warning: building a source package without cleaning up as you asked; it might contain undesired files
 dpkg-source -b .
dpkg-source: info: using source format '3.0 (native)'
dpkg-source: info: building ubuntu-advantage-tools in ubuntu-advantage-tools_27.14.4~22.04.tar.xz
dpkg-source: info: building ubuntu-advantage-tools in ubuntu-advantage-tools_27.14.4~22.04.dsc
 dpkg-genbuildinfo --build=source -O../ubuntu-advantage-tools_27.14.4~22.04_source.buildinfo
 dpkg-genchanges --build=source -v27.13.6 -O../ubuntu-advantage-tools_27.14.4~22.04_source.changes
dpkg-genchanges: warning: 'since' option specifies non-existing version '27.13.6'
dpkg-genchanges: warning: use newest entry that is earlier than the one specified
dpkg-genchanges: warning: the current version (27.14.4~22.04) is earlier than the previous one (27.14.4)
dpkg-genchanges: info: including full source code in upload
 dpkg-source --after-build .
dpkg-buildpackage: info: source-only upload: Debian-native package
 signfile ubuntu-advantage-tools_27.14.4~22.04.dsc
 signfile ubuntu-advantage-tools_27.14.4~22.04_source.buildinfo
 signfile ubuntu-advantage-tools_27.14.4~22.04_source.changes

[Robie Basak (racb)]

Fixed in 1.1.