fix(index): handle adding symlinks to dirs

When expanding directories, check if it is a symlink and don't expand
them at all.

Previously, we followed symlinks and expanded their contents, which
could lead to weird index files.

Fixes #302

1 files changed, 11 insertions, 0 deletions

diff --git a/git/index/base.py b/git/index/base.py
index 10de3358..f8696800 100644
--- a/git/index/base.py
+++ b/git/index/base.py
@@ -367,6 +367,17 @@ class IndexFile(LazyMixin, diff.Diffable, Serializable):
                 abs_path = os.path.join(r, path)
             # END make absolute path
 
+            try:
+                st = os.lstat(abs_path)     # handles non-symlinks as well
+            except OSError:
+                # the lstat call may fail as the path may contain globs as well
+                pass
+            else:
+                if S_ISLNK(st.st_mode):
+                    yield abs_path.replace(rs, '')
+                    continue
+            # end check symlink
+
             # resolve globs if possible
             if '?' in path or '*' in path or '[' in path:
                 for f in self._iter_expand_paths(glob.glob(abs_path)):