[RFC PATCH 0/5] Submodule Groups

This is also available at https://github.com/stefanbeller/git/tree/submodule-groups It applies on top of the submodule-parallel-patch series I sent a few minutes ago.

Consider having a real large software project in Git with each component in a submodule (such as an operating system, Android, Debian, Fedora, no toy OS such as https://github.com/gittup/gittup as that doesn't quite demonstrate the scale of the problem).

If you have lots of submodules, you probably don't need all of them at once, but you have functional units. Some submodules are absolutely required, some are optional and only for very specific purposes.

This patch series adds meaning to a "groups" field in the .gitmodules file.

So you could have a .gitmodules file such as:

[submodule "gcc"]
        path = gcc
        url = git://...
        groups = default,devel
[submodule "linux"]
        path = linux
        url = git://...
        groups = default
[submodule "nethack"]
        path = nethack
        url = git://...
        groups = optional,games

and by this series you can work on an arbitrary subgroup of these submodules such using these commands:

    git clone --group default --group devel git://...
    # will clone the superproject and recursively
    # checkout any submodule being in at least one of the groups.

    git submodule add --group default --group devel git://... ..
    # will add a submodule, adding 2 submodule
    # groups to its entry in .gitmodule
    
    # as support for clone we want to have:
    git config submodule.groups default
    git submodule init --groups
    # will init all submodules from the default group
    
    # as support for clone we want to have:
    git config submodule.groups default
    git submodule update --groups
    # will update all submodules from the default group

Any feedback welcome, specially on the design level! (Do we want to have it stored in the .gitmodules file? Do we want to have the groups configured in .git/config as "submodule.groups", any other way to make it future proof and extend the groups syntax?)

Thanks, Stefan

Stefan Beller (5):
  submodule-config: keep submodule groups around
  git submodule add can add a submodule with groups
  git submodule init to pass on groups
  submodule--helper: module_list and update-clone have --groups option
  builtin/clone: support submodule groups

 Documentation/git-clone.txt     |  11 ++++
 Documentation/git-submodule.txt |   8 ++-
 builtin/clone.c                 |  33 ++++++++++-
 builtin/submodule--helper.c     |  68 ++++++++++++++++++++++-
 git-submodule.sh                |  20 ++++++-
 submodule-config.c              |  14 +++++
 submodule-config.h              |   2 +
 t/t7400-submodule-basic.sh      | 118 ++++++++++++++++++++++++++++++++++++++++
 t/t7406-submodule-update.sh     |  32 +++++++++++
 9 files changed, 299 insertions(+), 7 deletions(-)