# HG changeset patch
# User Mads Kiilerich <madski@unity3d.com>
# Date 2014-10-03 00:20:36
# Node ID 18f6bdd1e3fc81972eb52398a295921380a98271
# Parent  cb360bf4086368949a90cc01740bfef3a3e4db21

hg: make get_ref_revision('rev', '00000000000000') give the null revision

It gave tip revision and caused weird pull request diffs and lots of grief when
(accidentally) creating a pull request from the null revision.

diff --git a/kallithea/lib/vcs/backends/hg/repository.py b/kallithea/lib/vcs/backends/hg/repository.py
--- a/kallithea/lib/vcs/backends/hg/repository.py
+++ b/kallithea/lib/vcs/backends/hg/repository.py
@@ -452,6 +452,8 @@ class MercurialRepository(BaseRepository
         Returns revision number for the given reference.
         """
         ref_name = safe_str(ref_name)
+        if ref_type == 'rev' and not ref_name.strip('0'):
+            return self.EMPTY_CHANGESET
         # lookup up the exact node id
         _revset_predicates = {
                 'branch': 'branch',