Re: [PATCH] git-submodule add: Record branch name in .gitmodules

On Mon, Oct 22, 2012 at 6:55 PM, W. Trevor King [off-list ref] wrote:

On a tangentially related note, it would be nice to set environment
variables for each of the settings in submodule.$name during a foreach
call.  Then you could use

  git submodule foreach 'git checkout $branch && git pull'

Perhaps you'd want to blacklist/whitelist or downcase settings names
to avoid things like

  [submodule "foo"]
        PATH = /my/rootkit/

but the update line is much cleaner.

This is ugly as can be, but it works in my meagre testing.  It defines
"submodule_path=/my/rootkit/" for the above bit of .gitmodules.  That
is, it adds definitions for 'submodule_<var-name>' for each <var-name>
in .gitmodules in submodule.$name.<var-name>, but <var-name> is
lowercased and defanged (everything that's not already [a-z0-9] is
replaced with underscore).  For example,

  git submodule foreach 'echo $submodule_url'

--- >8 ---
diff --git c/git-submodule.sh i/git-submodule.sh
index 6dd2338..79b3467 100755
--- c/git-submodule.sh
+++ i/git-submodule.sh

@@ -416,7 +416,15 @@ cmd_foreach()
                                prefix="$prefix$sm_path/"
                                clear_local_git_env
                                # we make $path available to scripts ...
                                path=$sm_path
+
+                               # make all submodule variables

available to scripts
+                               eval $(git config -f .gitmodules
--get-regexp "^submodule\.${name}\..*" |
+                               sed -e "s|^submodule\.${name}\.||" |
+                               while read VAR_NAME VAR_VALUE ; do
+                                       VAR_NAME=$(printf '%s'
"$VAR_NAME" | tr A-Z a-z | sed -e 's/^[^a-z]/_/' -e 's/[^a-z0-9]/_/g')
+                                       printf 'submodule_%s=%s;\n'
"$VAR_NAME" "'$VAR_VALUE'"
+                               done)
                                cd "$sm_path" &&
                                eval "$@" &&
                                if test -n "$recursive"