# HG changeset patch
# User Durham Goode <durham@fb.com>
# Date 1441670915 25200
# Node ID 327d09f0b5d48f4aaa02e13966dec84a15594c61
# Parent  bf1b24785f13c91c32a95c762ce586833586a8c9
exchange: allow fallbackheads to use lazy set behavior

The common ancestor set implementation was made lazy a couple years ago, but
this piece of code still required processing the entire repo by putting set()
around the lazy set. The code was introduced in 5653f2d166ea, a year before the
lazy ancestor set was added.

Dropping the set() shaves 3.5 seconds off of 'push -r' in repos with hundreds of
thousands of commits.

diff -r bf1b24785f13 -r 327d09f0b5d4 mercurial/exchange.py
--- a/mercurial/exchange.py	Sat Aug 22 16:38:51 2015 -0700
+++ b/mercurial/exchange.py	Mon Sep 07 17:08:35 2015 -0700
@@ -147,7 +147,7 @@
         #
         # We can pick:
         # * missingheads part of common (::commonheads)
-        common = set(self.outgoing.common)
+        common = self.outgoing.common
         nm = self.repo.changelog.nodemap
         cheads = [node for node in self.revs if nm[node] in common]
         # and