# HG changeset patch
# User Stanislau Hlebik <stash@fb.com>
# Date 2017-02-13 10:26:18
# Node ID 6037caa6a2f366b614ab29460a26b92d94e0fd50
# Parent  76a1e735449ca8c2e93ca6823fefdcb5fc242572

localrepo: cache self.changelog in local variable

Repeated self.changelog lookups can incur overhead. Let's cache it in the
separate variable.

diff --git a/mercurial/localrepo.py b/mercurial/localrepo.py
--- a/mercurial/localrepo.py
+++ b/mercurial/localrepo.py
@@ -1853,8 +1853,9 @@ class localrepository(object):
 
     def heads(self, start=None):
         if start is None:
-            headrevs = sorted(self.changelog.headrevs(), reverse=True)
-            return [self.changelog.node(rev) for rev in headrevs]
+            cl = self.changelog
+            headrevs = sorted(cl.headrevs(), reverse=True)
+            return [cl.node(rev) for rev in headrevs]
 
         heads = self.changelog.heads(start)
         # sort the output in rev descending order