Deinitialize a submodule and merge it as a branch

deinit.sh

#!/bin/bash -xe
deinit() {
	module_path=$1
	test -d $module_path
	current_branch=$(git rev-parse --abbrev-ref HEAD)
	url=$(cd $module_path; git config --get remote.origin.url)
	remote_name=$(basename $url)
	branch_name=$(basename $url)
	head=$(cd $module_path; git rev-parse HEAD)

	git remote add -f $remote_name $url
	git checkout -fb $branch_name $head
	rm -rf $module_path

	git filter-branch -f --index-filter \
		'git ls-files -s | gsed "s-\t\"*-&'$module_path'/-" |
GIT_INDEX_FILE=$GIT_INDEX_FILE.new \
git update-index --index-info &&
mv "$GIT_INDEX_FILE.new" "$GIT_INDEX_FILE"'

	git checkout $current_branch
	git submodule deinit $module_path
	git rm -rf $module_path
	git commit -m "Remove $module_path as a submodule"
	git merge $branch_name
	git branch -d $branch_name
}

deinit $1