Question

This seems a to be a common issue, but i just can’t find a reasonable solution:
IMHO, the worse problem with git submodules is where submodule committed but not pushed changes are easily deleted with the containing repository usage of git submodule update. Quoting:

It’s not safe to run git submodule update if you’ve made and committed
changes within a submodule without checking out a branch first. They
will be silently overwritten:

(…followed by an example there).

So, to the question-
Let super be a repository root folder and submod be a child folder containing a submodule:

-super   
     -submod

When i commit in the submodule but not push, and then run git submodule update i get my committed changes in submod deleted (oh, the horror).
How can i add a confirmation are you sure question when i’m doing this?
hooks, scripts or any other applicable ideas are more the welcome.

TIA

Answer 1

There’s no hook for pre-submodule-update, so what you’d probably need to do is instead write a script that you use instead of git submodule update.

A simple way to see if you have any modified submodules is this:

if git submodule status | grep -q '^+'; then
    # at least one submodule has changes
fi

Also note that if an accidental update blows away your changes, you might still be able to salvage them via the submodule checkout’s reflog (since submodule checkouts are effectively full Git repositories in their own right).