[PATCH 10 of 10 py3] localrepo: forcibly copy list of filecache keys

[Augie Fackler]

# HG changeset patch
# User Augie Fackler <augie at google.com>
# Date 1489900260 14400
#      Sun Mar 19 01:11:00 2017 -0400
# Node ID 3e3eff548aecf281d22c70ba853c0f742fd6c64b
# Parent  ce928383cf5dfb0993d27340b3fcf936a129e0fb
localrepo: forcibly copy list of filecache keys

On Python 3, keys() is more like iterkeys(), so we got in trouble for
mutating the dict while we're iterating here. Since the list of caches
should be relatively small, work around this difference by just
forcing a copy of the key list.

diff --git a/mercurial/localrepo.py b/mercurial/localrepo.py
--- a/mercurial/localrepo.py
+++ b/mercurial/localrepo.py
@@ -1318,7 +1318,7 @@ class localrepository(object):
         redundant one doesn't).
         '''
         unfiltered = self.unfiltered() # all file caches are stored unfiltered
-        for k in self._filecache.keys():
+        for k in list(self._filecache.keys()):
             # dirstate is invalidated separately in invalidatedirstate()
             if k == 'dirstate':
                 continue