prune: handle branches that track missing branches

Series of steps:
* Create a local "b1" branch with `repo start b1` that tracks a remote
  branch (totally fine)
* Manually create a local "b2" branch with `git branch --track b1 b2`
  that tracks the local "b1" (uh-oh...)
* Delete the local "b1" branch manually or via `repo prune` (....)
* Try to process the "b2" branch with `repo prune`

Since b2 tracks a branch that no longer exists, everything blows up
at this point as we try to probe the non-existent ref.  Instead, we
should flag this as unknown and leave it up to the user to resolve.

This probably could come up if a local branch was tracking a remote
branch that was deleted from the server, and users ran something like
`repo sync --prune` which cleaned up the remote refs.

Bug: https://crbug.com/gerrit/11485
Change-Id: I6b6b6041943944b8efa6e2ad0b8b10f13a75a5c2
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/236793
Reviewed-by: David Pursehouse <dpursehouse@collab.net>
Reviewed-by: Kirtika Ruchandani <kirtika@google.com>
Reviewed-by: Mike Frysinger <vapier@google.com>
Tested-by: Mike Frysinger <vapier@google.com>
3 files changed
tree: 4962f9913b689de734d3d11e981d3a2e18841504
  1. docs/
  2. hooks/
  3. subcmds/
  4. tests/
  5. .flake8
  6. .gitattributes
  7. .gitignore
  8. .mailmap
  9. .project
  10. .pydevproject
  11. color.py
  12. command.py
  13. COPYING
  14. editor.py
  15. error.py
  16. event_log.py
  17. git_command.py
  18. git_config.py
  19. git_refs.py
  20. git_ssh
  21. gitc_utils.py
  22. main.py
  23. manifest_xml.py
  24. pager.py
  25. platform_utils.py
  26. platform_utils_win32.py
  27. progress.py
  28. project.py
  29. pyversion.py
  30. README.md
  31. repo
  32. repo_trace.py
  33. run_tests
  34. SUBMITTING_PATCHES.md
  35. wrapper.py
README.md

repo

Repo is a tool built on top of Git. Repo helps manage many Git repositories, does the uploads to revision control systems, and automates parts of the development workflow. Repo is not meant to replace Git, only to make it easier to work with Git. The repo command is an executable Python script that you can put anywhere in your path.