Re: Integrating submodules with no side effects

From: Stefan Beller <sbeller@google.com>
Date: Oct 18, 2016, 21:17 UTC
Message-ID: <CAGZ79kaFtzQDZrSJhJZ59xvBzn+6+UVDO65Ac+T6aFxMQaM_xQ@mail.gmail.com>
In-Reply-To: <CAHd499AN2VHL66c6JWxHqS-1bQ6y4PrGjZJiR_ad6HJsCGpeDQ@mail.gmail.com>

On Tue, Oct 18, 2016 at 12:35 PM, Robert Dailey <rcdailey.lists@gmail.com> wrote:

Show 28 quoted lines

> Hello git experts,
>
> I have in the past attempted to integrate submodules into my primary
> repository using the same directory name. However, this has always
> caused headache when going to and from branches that take you between
> when this integration occurred and when it didn't. It's a bit hard to
> explain. Basically, if I have a submodule "foo", and I delete that
> submodule and physically add its files under the same directory "foo",
> when I do a pull to get this change from another clone, it fails
> saying:
>
> error: The following untracked working tree files would be overwritten
> by checkout:
>         foo/somefile.txt
> Please move or remove them before you switch branches.
> Aborting
> could not detach HEAD
>
>
> Obviously, git can't delete the submodule because the files have also
> been added directly. I don't think it is built to handle this
> scenario. Here is the series of commands I ran to "integrate" the
> submodule (replace the submodule with a directory containing the exact
> contents of the submodule itself):
>
> #!/usr/bin/env bash
> mv "$1" "${1}_"
> git submodule deinit "$1"

This removes the submodule entries from .git/config (and it would remove the contents of that submodule, but they are moved)

> git rm "$1"

Removing the git link here.

So we still have the entries in the .gitmodules file there. Maybe add:

    name=$(git submodule-helper name $1)
    git config -f .gitmodules --unset submodule.$name.*
    git add .gitmodules

? (Could be optional)

> mv "${1}_" "$1"
> git add "$1/**"

Moving back into place and adding all files in there.

Show 10 quoted lines

>
> The above script is named git-integrate-submodule, I run it like so:
>
> $ git integrate-submodule foo
>
> Then I do:
>
> $ git commit -m 'Integrated foo submodule'
>
> Is there any way to make this work nicely?

I think you can just remove the gitlink from the index and not from the working tree ("git rm --cached $1")

> The only solution I've
> found is to obviously rename the directory before adding the physical
> files, for example name it foo1. Because they're different, they never
> "clash".

Also look at the difference between plumbing and porcelain commands[1], as plumbing is more stable than the porcelain, so it will be easier to maintain this script.

I think this would be an actually reasonable feature, which Git itself could support via "git submodule [de]integrate", but then we'd also want to see the reverse, i.e. take a sub directory and make it a submodule.

[1] e.g. https://www.kernel.org/pub/software/scm/git/docs/

Thanks, Stefan