Update a submodule to the latest commit

Question

I have a project A which is a library and it is used in a project B.

Both projects A and B have a separate repository on github BUT inside B we have a submodule of A.

I edited some classes on the library, which is in the repo A, I pushed on the remote repo, so the library (repo A) is updated.

These updates do not reflect on the "reference" (the submodule) the submodule refers to a previous commit.... what should I do in order to update the submodule on git?

Answer 1

Enter the submodule directory:

cd projB/projA 

Pull the repo from you project A (will not update the git status of your parent, project B):

git pull origin master 

Go back to the root directory & check update:

cd .. git status 

If the submodule updated before, it will show something like below:

# Not currently on any branch. # Changed but not updated: #   (use "git add ..." to update what will be committed) #   (use "git checkout -- ..." to discard changes in working directory) # #       modified:   projB/projA (new commits) # 

Then, commit the update:

git add projB/projA git commit -m "projA submodule updated" 

---

UPDATE

As @paul pointed out, since git 1.8, we can use

git submodule update --remote --merge 

to update the submodule to the latest remote commit. It'll be convenient in most cases.

Answer 2

Since git 1.8 you can do

git submodule update --remote --merge 

This will update the submodule to the latest remote commit. You will then need to add and commit the change so the gitlink in the parent repository is updated:

First, git add it

git add project/submodule_proj_name 

then git commit it

git commit -m 'gitlink to submodule_proj_name was updated' 

the git push it

git push 

And then push the changes as without this, the SHA-1 identity the pointing to the submodule won't be updated and so the change won't be visible to anyone else.