# HG changeset patch
# User Gregory Szorc <gregory.szorc@gmail.com>
# Date 2018-08-07 17:24:49
# Node ID 4f06e0360bad2ed6533e899a0e47793ce601b120
# Parent  633249d226c74c1fe4467aaa3f9c1bcdbe10e733

changegroup: restore original behavior of _nextclrevtolocalrev

0548f696795b accidentally changed the behavior of cgpacker._close().
The old behavior moved _nextclrevtolocalrev to _clrevtolocalrev only
when _nextclrevtolocalrev was present and then removed
_nextclrevtolocalrev. The bad behavior performed this move
then cleared _clrevtolocalrev because it was the same object as
_nextclrevtolocalrev.

This commit restores the previous behavior.

Surprisingly, no tests changed as a result of this bad logic. I'm
not sure why.

Differential Revision: https://phab.mercurial-scm.org/D4155

diff --git a/mercurial/changegroup.py b/mercurial/changegroup.py
--- a/mercurial/changegroup.py
+++ b/mercurial/changegroup.py
@@ -604,9 +604,9 @@ class cgpacker(object):
     def _close(self):
         # Ellipses serving mode.
         self._clrevtolocalrev.clear()
-        if self._nextclrevtolocalrev:
+        if self._nextclrevtolocalrev is not None:
             self._clrevtolocalrev = self._nextclrevtolocalrev
-            self._nextclrevtolocalrev.clear()
+            self._nextclrevtolocalrev = None
         self._changelogdone = True
 
         return closechunk()