[PATCH 0/4] implement automatic submodule merge strategy when possible

This series implements a semi-automatic submodule merge as was discussed in this thread:

http://thread.gmane.org/gmane.comp.version-control.git/148942

In short:

Suppose we merge two submodule hashes A and B. If either A->B or B->A is a fast-forward the automatic result is the one containing both.

If there is not direct relation between A and B but we find a merge on any ref that contains both we suggest this as a possible resolution to the user. If there are more merges we output a list of them.

The suggestion tells the user to use update-index because checkout_submodule() on which Jens is working is not finished yet. This is a temporary solution and we can automatically checkout a submodule later when this is implemented.

Note: As I am not that familiar with the git codebase yet another pair
of eyes would be really appreciated.

The newest version of this series can always be found on

git://github.com/hvoigt/git.git

Branch: submodule_merge_v2

Heiko Voigt (4):
  add missing && to submodule-merge testcase
  teach ref iteration module about submodules
  extent setup_revisions() so it works with submodules
  implement automatic fast forward merge for submodules

 cache.h                    |    3 +
 merge-recursive.c          |    9 ++-
 path.c                     |   38 +++++++++++
 refs.c                     |  130 +++++++++++++++++++++++++++++--------
 refs.h                     |    8 ++
 revision.c                 |   32 +++++----
 revision.h                 |    1 +
 submodule.c                |  154 ++++++++++++++++++++++++++++++++++++++++++++
 submodule.h                |    2 +
 t/t7405-submodule-merge.sh |  124 +++++++++++++++++++++++++++++++++--
 10 files changed, 450 insertions(+), 51 deletions(-)