Force Git submodules to always stay current
I love git submodules. Also, I hate git submodules. What I love about them is how it enables to you to cleanly compartmentalize dependencies etc. I get the point of having them point to a specific commit on a repo, I do. But in my case, I'm building a library that will be used in another project, so I want to keep it in that seperate repo.
However, the annoyance comes when I'm working on a daily basis on this library and I constantly have to switch back to the app using my library to commit the pointer update.
So, is it possible to have a git submodule just always be on the head of the repo it's pointing at while I'm constantly updating and adding to this library?
Answer
As I mention in "git submodule tracking latest", you can since git 1.8.2 (March 2013) make a submodule track the HEAD of branch:
git submodule add -b <branch> <repository> [<path>]
A submodule SHA1 is still recorded in the parent repo as a gitlink (special entry in the index)
But a git submodule update --remote will update that entry to the SHA1 matching the HEAD of a branch of the submodule remote repo.
If you have an existing submodule, you can make it follow a branch with:
cd /path/to/your/parent/repo
git config -f .gitmodules submodule.<path>.branch <branch>
cd path/to/your/submodule
git checkout -b branch --track origin/branch
# if the master branch already exist:
git branch -u origin/master master
cd /path/to/your/parent/repo
git add path/to/your/submodule
git commit -m "Make submodule tracking a branch"