filter-branch: Fix renaming a directory in the tree-filter
Commit d89c1df (filter-branch: don't use xargs -0, 2008-03-12) replaced a 'ls-files | xargs rm' pipeline by 'git clean'. 'git clean' however does not recurse and remove directories by default.
Now, consider a tree-filter that renames a directory.
1. For the first commit everything works as expected
2. Then filter-branch checks out the files for the next commit. This leaves the new directory behind because there is no real "branch switching" involved that would notice that the directory can be removed.
3. Then filter-branch invokes 'git clean' to remove exactly those left-overs. But here it does not remove the directory.
4. The next tree-filter does not work as expected because there already exists a directory with the new name.
Just add -d to 'git clean', so that empty directories are removed.
Signed-off-by: Johannes Sixt <firstname.lastname@example.org> Signed-off-by: Junio C Hamano <email@example.com>