Support multiple refspecs in fetch.

Git supports fetching many refs at once - support this in GitPython too for more efficient operations when selectively mirroring repositories.

Author: rbtcollins

git/remote.py

@@ -583,6 +583,10 @@ def fetch(self, refspec=None, progress=None, **kwargs):
  See also git-push(1).
 
  Taken from the git manual
+
+ Fetch supports multiple refspecs (as the
+ underlying git-fetch does) - supplying a list rather than a string
+ for 'refspec' will make use of this facility.
  :param progress: See 'push' method
  :param kwargs: Additional arguments to be passed to git-fetch
  :return:
@@ -593,7 +597,11 @@ def fetch(self, refspec=None, progress=None, **kwargs):
  As fetch does not provide progress information to non-ttys, we cannot make 
  it available here unfortunately as in the 'push' method."""
 kwargs=add_progress(kwargs, self.repo.git, progress)
-proc=self.repo.git.fetch(self, refspec, with_extended_output=True, as_process=True, v=True, **kwargs)
+ifisinstance(refspec, list):
+args=refspec
+else:
+args= [refspec]
+proc=self.repo.git.fetch(self, *args, with_extended_output=True, as_process=True, v=True, **kwargs)
 returnself._get_fetch_info_from_stderr(proc, progressorRemoteProgress())
 
 defpull(self, refspec=None, progress=None, **kwargs):

git/test/test_remote.py

@@ -199,6 +199,10 @@ def get_info(res, remote, name):
 # ... with respec and no target
 res=fetch_and_test(remote, refspec='master')
 assertlen(res) ==1
+
+# ... multiple refspecs
+res=fetch_and_test(remote, refspec=['master', 'fred'])
+assertlen(res) ==1
 
 # add new tag reference
 rtag=TagReference.create(remote_repo, "1.0-RV_hello.there")