Git submodules removing on checkout another branch

Question

I have several branches with features in my Git repo.
Every feature is some foreign repo, plugged in as a submodule.
What should I do to correct switching between branches, with and without submodules?

Example:

$ git init
$ git commit -m "empty" --allow-empty
$ git checkout -b feature
$ git submodule init
$ git submodule add git://feature.git feature
$ git commit -a -m "add feature"
$ git checkout master
warning: unable to rmdir feature: Directory is not empty

And we have a feature in our master branch work directory.
How to prevent this?

Answer 1

git submodule deinit .

may do the trick

Answer 2

It seems the easiest way is manually deleting the submodule directories. The price is you have to git submodule init && git submodule update after every checkout.

To match the directories from .gitmodules:

grep path .gitmodules | sed 's/.*= //'

*From Prelang/gist/git-submodule-names

To remove it:

grep path .gitmodules | sed 's/.*= //' | xargs rm -rf