[RFC PATCH 0/2] share a config between submodule and superproject

Hi folks,

Especially after es/config-based-hooks makes its way to 'next' and 'master', we think it would be really useful to have a config that applies to a whole "project" - where "project" means "superproject and its submodules." There's a longer defense in patch 2, but that's the speedy summary.

I'm not wild about the implementation of this solution as it calls out to 'git rev-parse' and 'git ls-files' - not once, but twice! - and I understand that is considerably slower on some platforms than others. But I'm open to suggestions - I couldn't find any other examples of a repo figuring out whether it's a submodule or not. (I thought there may be some, as 'repository.submodule_prefix' exists, but it seems like that's only set in some special cases during operations initated from the superproject.)

I'm hoping to work on some other submodule-centric stuff over the coming months, and it might end up being very useful to be able to tell "am I a submodule?" and "how do I talk to my superproject?" more generally - so I'm really open to figuring out a better way than this, if folks have ideas.

Patch 1 is a small refactor that we can take or leave - I found "SCOPE_SUBMODULE" to be pretty ambiguous, especially since it seems to refer to configs from .gitmodules. Even though I decided that "superproject" was a better name than "submodule" I still wasn't super happy with the ambiguity. But we can drop it if folks don't want to rename.

Thanks a bunch,
 - Emily

Emily Shaffer (2):
  config: rename "submodule" scope to "gitmodules"
  config: add 'config.superproject' file

 Documentation/git-config.txt   |  21 +++++-
 builtin/config.c               |  10 ++-
 config.c                       |  30 +++++++-
 config.h                       |   5 +-
 submodule-config.c             |   2 +-
 submodule.c                    |  29 ++++++++
 submodule.h                    |   6 ++
 t/t1311-superproject-config.sh | 124 +++++++++++++++++++++++++++++++++
 8 files changed, 220 insertions(+), 7 deletions(-)
 create mode 100755 t/t1311-superproject-config.sh