[PATCHv3 00/21] git notes merge

Hi,

This is the 3rd iteration of the 'git notes merge' patch series.

Changes between v2 and v3:

- Add initial patch fixing a missing sha1_to_hex() call in die() message
  from init_notes().

- (Ævar Arnfjörð Bjarmason) Don't use C99 comments.

- (Ævar Arnfjörð Bjarmason) Fix nonsense sentence in --commit description

- (Stephen Boyd) Use correct option name

- (Stephen Boyd) Remove unbalanced '('

- (Jonathan Nieder) Split the function reordering from (then) patch
  #3 into a separate patch (now patch #4), preceding the rest of the
  original patch (now patch #5). Also, clarify the behavioural change
  of that patch in its commit message.
  
- (Jonathan Nieder) Describe in the commit message how existing callers
  of add_note() are modified to deal with add_note()'s return value.

- (Jonathan Nieder) Add patch implementing 'git notes get-ref'

To be done in later series:

- Handle merging of notes trees with non-notes

- Allow notes merge strategies to be specified (per (group of?) notes
  ref) in the config

Some open questions:

- Sverre Rabbelier suggests renaming 'git notes merge --reset' to
  'git notes merge --abort'. I sort of agree, but would want some
  consistency with 'git merge', e.g. by providing 'git merge --abort'
  as an alias to 'git reset --merge'.

- Should we refuse to finalize a notes merge when conflict markers
  present in .git/NOTES_MERGE_WORKTREE? Since add/commit in regular
  merges does NOT do this, I have not implemented it for notes merge.

- When resolving notes merge conflicts, you can add/remove files/notes
  in .git/NOTES_MERGE_WORKTREE; 'git notes merge --commit' does not
  check that the notes have any relationship to the notes originally
  put there by 'git notes merge'. Should we warn about removed and
  added notes in .git/NOTES_MERGE_WORKTREE? Currently we don't, and
  I'm not sure it's worth it. Users can always review the merge commit
  afterwards.

- Fetching and pushing note refs:
  - Add refs/notes/* to default fetch refspec?
  - A way to specify (at clone time) which refspec(s) to set up?
  - A way for the remote repo to hint at which refspecs you might want
    to set up (by default?)

Have fun! :)

...Johan

Johan Herland (21):
  notes.c: Hexify SHA1 in die() message from init_notes()
  (trivial) notes.h: Minor documentation fixes to copy_notes()
  notes.h: Make default_notes_ref() available in notes API
  notes.c: Reorder functions in preparation for next commit
  notes.h/c: Clarify the handling of notes objects that are == null_sha1
  notes.h/c: Propagate combine_notes_fn return value to add_note() and beyond
  (trivial) t3303: Indent with tabs instead of spaces for consistency
  notes.c: Use two newlines (instead of one) when concatenating notes
  builtin/notes.c: Split notes ref DWIMmery into a separate function
  git notes merge: Initial implementation handling trivial merges only
  builtin/notes.c: Refactor creation of notes commits.
  git notes merge: Handle real, non-conflicting notes merges
  git notes merge: Add automatic conflict resolvers (ours, theirs, union)
  Documentation: Preliminary docs on 'git notes merge'
  git notes merge: Manual conflict resolution, part 1/2
  git notes merge: Manual conflict resolution, part 2/2
  git notes merge: List conflicting notes in notes merge commit message
  git notes merge: --commit should fail if underlying notes ref has moved
  git notes merge: Add another auto-resolving strategy: "cat_sort_uniq"
  git notes merge: Add testcases for merging notes trees at different fanouts
  Provide 'git notes get-ref' to easily retrieve current notes ref

 Documentation/git-notes.txt           |   85 ++++-
 Makefile                              |    2 +
 builtin.h                             |    2 +-
 builtin/notes.c                       |  268 +++++++++++--
 notes-cache.c                         |    3 +-
 notes-merge.c                         |  718 +++++++++++++++++++++++++++++++++
 notes-merge.h                         |   97 +++++
 notes.c                               |  274 +++++++++-----
 notes.h                               |   47 ++-
 t/t3301-notes.sh                      |   23 +
 t/t3303-notes-subtrees.sh             |   19 +-
 t/t3308-notes-merge.sh                |  327 +++++++++++++++
 t/t3309-notes-merge-auto-resolve.sh   |  647 +++++++++++++++++++++++++++++
 t/t3310-notes-merge-manual-resolve.sh |  556 +++++++++++++++++++++++++
 t/t3311-notes-merge-fanout.sh         |  436 ++++++++++++++++++++
 t/t3404-rebase-interactive.sh         |    1 +
 t/t9301-fast-import-notes.sh          |    5 +
 17 files changed, 3367 insertions(+), 143 deletions(-)
 create mode 100644 notes-merge.c
 create mode 100644 notes-merge.h
 create mode 100755 t/t3308-notes-merge.sh
 create mode 100755 t/t3309-notes-merge-auto-resolve.sh
 create mode 100755 t/t3310-notes-merge-manual-resolve.sh
 create mode 100755 t/t3311-notes-merge-fanout.sh