Git Submodules

Add New Submodules

git submodule add -b <branch> <repository> [<submodule-path>]
git submodule update --remote

Remove Submodules

# Delete the relevant section from .gitmodules
git add .gitmodules
# Delete the relevant section from .git/config
git rm --cached path_to_submodule   # no trailing slash
rm -rf .git/modules/path_to_submodule
git commit -m "Removed submodule <name>"
rm -rf path_to_submodule

Submodule Detached HEAD

If a submodule ends up with a detached HEAD:

cd <submodule-path>
git checkout <branch>
git branch -u refs/remotes/origin/master master

Check .gitmodule and .git/config, or:

cd <submodule-path>
git checkout <branch>
cd <parent-repo-path>
git config -f .gitmodules submodule.<submodule-path>.branch <branch>