[PATCH 1/2] filter-branch: Fix to allow replacing submodules with another content

When git filter-branch is used to replace a submodule with another content, it always fails on the first commit. Consider a repository with submod directory containing a submodule. If I want to remove the submodule and replace it with a file, the following command fails.

git filter-branch --tree-filter 'rm -rf submod &&
				 git rm -q submod &&
				 mkdir submod &&
				 touch submod/file'

The error message is: error: submod: is a directory - add files inside instead

The reason is that git diff-index, which generates the first part of the list of files updated by the tree filter, emits also the removed submodule even if it was replaced by a real directory.

Adding --ignored-submodules solves the problem for me and tests in t7003-filter-branch.sh pass correctly.

If somebody wants to replace one revision of the module with another, it
can be done with --index-filter. Using --tree-filter for this has no
sense since --tree-filter "git submodule update --init" fails with
  Clone of '/tmp/submod' into submodule path 'submod' failed
so that the revision must be replaced only in index.

Signed-off-by: Michal Sojka <sojkam1@fel.cvut.cz>
---
 git-filter-branch.sh |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)