use git rev-parse to look for config file

Author: bdauvergne

git/repo/base.py

@@ -202,14 +202,21 @@ def __init__(self, path=None, odbt=GitCmdObjectDB, search_parent_directories=Fal
         # END working dir handling
 
         self.working_dir = self._working_tree_dir or self.common_dir
-        self.git = self.GitCommandWrapperType(self.working_dir)
 
         # special handling, in special times
         args = [osp.join(self.common_dir, 'objects')]
         if issubclass(odbt, GitCmdObjectDB):
             args.append(self.git)
         self.odb = odbt(*args)
 
+    class GitCommand(object):
+        def __get__(self, instance, owner):
+            if instance is not None:
+                return instance.GitCommandWrapperType(instance._working_tree_dir or instance.common_dir)
+            raise AttributeError('git')
+
+    git = GitCommand()
+
     def __enter__(self):
         return self
 
@@ -431,7 +438,12 @@ def _get_config_path(self, config_level):
         elif config_level == "global":
             return osp.normpath(osp.expanduser("~/.gitconfig"))
         elif config_level == "repository":
-            return osp.normpath(osp.join(self._common_dir or self.git_dir, "config"))
+            try:
+                config_path = self.git.rev_parse("config", git_path=True)
+            except GitCommandError:
+                return osp.normpath(osp.join(self._common_dir or self.git_dir, "config"))
+            else:
+                return osp.normpath(osp.join(self.git._working_dir, config_path))
 
         raise ValueError("Invalid configuration level: %r" % config_level)