Tags · chooglen/git

fetch-init-from-superproejct-tree

submodule: init from superproject tree when checking for commits

To minimize the number of fetches, "fetch --recurse-submodules" checks
if the 'changed' commits are already in the submodule, and skips the
fetch if the submodule already has all of the commits. To make this work
with submodules that are not in the index, we need to teach
submodule_has_commits() to init the submodule from a superproject tree
instead of reading `.gitmodules` from the filesystem. This does not
change the existing behavior because Git still inits the same submodule
when checking for commits, just that it uses the `.gitmodules` and path
from the super_oid tree.

Add super_oid to struct changed_submodule_data and use super_oid when
Git calls submodule_has_commits() during "fetch --recurse-submodules".
Do not change the submodule_has_commits() call during "push
--recurse-submodules".

Signed-off-by: Glen Choo <chooglen@google.com>