Auto-update odb caches after fetch or pull.

Fixes #34

Author: Byron

doc/source/changes.rst

@@ -6,6 +6,7 @@ Changelog
 ================
 * push/pull/fetch operations will not block anymore
 * diff() can now properly detect renames, both in patch and raw format. Previously it only worked when create_patch was True.
+* repo.odb.update_cache() is now called automatically after fetch and pull operations. In case you did that in your own code, you might want to remove your line to prevent a double-update that causes unnecessary IO.
 * A list of all fixed issues can be found here: https://github.com/gitpython-developers/GitPython/issues?q=milestone%3A%22v0.3.5+-+bugfixes%22+
 
 0.3.4 - Python 3 Support

git/remote.py

@@ -610,7 +610,9 @@ def fetch(self, refspec=None, progress=None, **kwargs):
             args = [refspec]
 
         proc = self.repo.git.fetch(self, *args, with_extended_output=True, as_process=True, v=True, **kwargs)
-        return self._get_fetch_info_from_stderr(proc, progress or RemoteProgress())
+        res = self._get_fetch_info_from_stderr(proc, progress or RemoteProgress())
+        self.repo.odb.update_cache()
+        return res
 
     def pull(self, refspec=None, progress=None, **kwargs):
         """Pull changes from the given branch, being the same as a fetch followed
@@ -622,7 +624,9 @@ def pull(self, refspec=None, progress=None, **kwargs):
         :return: Please see 'fetch' method """
         kwargs = add_progress(kwargs, self.repo.git, progress)
         proc = self.repo.git.pull(self, refspec, with_extended_output=True, as_process=True, v=True, **kwargs)
-        return self._get_fetch_info_from_stderr(proc, progress or RemoteProgress())
+        res = self._get_fetch_info_from_stderr(proc, progress or RemoteProgress())
+        self.repo.odb.update_cache()
+        return res
 
     def push(self, refspec=None, progress=None, **kwargs):
         """Push changes from source branch in refspec to target branch in refspec.