Re: Moving (renaming) submodules, recipe/script

[Jonathan Nieder <jrnieder@gmail.com>]

(just cc-ing Jens and Peter, who might be interested)

W. Trevor King wrote:

> Today I had to move my first submodule, and I discovered that Git's
> support for this is pretty limited.  There have been a few patch
> series attempting to address this [1,2], but none of them seems to
> have pushed through into master (although I can't put my finger on a
> reason for why).  There are also some SO postings discussing this
> [3,4].  It would be nice if `git mv` worked out of the box on
> submodules.  Failing that, there could be a `git submodule mv` command
> that casts the appropriate spell.  Failing that, there could be a
> recipe in Documentation/git-submodule.txt.  Here's the best I could
> come up with for a `git-submodule-mv.sh`:
>
>   #!/bin/sh
>   # usage: git-submodule-mv.sh OLD NEW
>   OLD=$(realpath --relative-to . "$1")
>   NEW=$(realpath --relative-to . "$2")
>   SHA=$(git ls-files -s "$OLD" | sed 's|^[0-9]* \([0-9a-f]*\) .*|\1|')
>   NAME=$(git config -f .gitmodules --get-regexp 'submodule\..*\.path' "$OLD" |
>     sed -e 's|^submodule.||' -e "s|.path $OLD\$||")
>   GITDIR=$(realpath --relative-to "$NEW" .git/modules/"$NAME")
>   git config -f .gitmodules submodule."$NAME".path "$NEW"
>   git config -f .git/modules/"$NAME"/config core.worktree "../../../$NEW"
>   git rm --cached "$OLD"
>   mv "$OLD" "$NEW"
>   echo "gitdir: $GITDIR" > "$NEW/.git"
>   git update-index --add --cacheinfo 160000 "$SHA" "$NEW"
>
> This only works from the repository root directory, and I'm sure makes
> a number of poor assumptions (e.g. old-style submodules that don't use
> `gitdir` links are not supported).  It does work for some simple test
> cases.  The tricky parts (e.g. path -> name conversion) are already
> worked out more robustly git-submodule.sh, so adding a new cmd_mv
> shouldn't be very difficult.
>
> Could something like this live somewhere in Git, or are we waiting for
> a more integrated solution?
>
> Cheers,
> Trevor
>
> [1]: http://thread.gmane.org/gmane.comp.version-control.git/88720
> [2]: http://thread.gmane.org/gmane.comp.version-control.git/143250
> [4]: http://stackoverflow.com/questions/4323558/moving-submodules-with-git
> [3]: http://stackoverflow.com/questions/4604486/how-do-i-move-an-existing-git-submodule-within-a-git-repository