LP #142667: ensure _reader uses new cache in _resetCache.

NEWS.txt

-What's new in ZODB3 3.6.3?
+What's new in ZODB3 3.6.4?
 ==========================
-Release date: 03-Jul-2007
+Release date: DD-MMM-YYYY
+
+Connection
+----------
 
+- (3.6.4) Reset ``_cache`` on a connection's ``_reader`` object when
+  resetting the cache, to prevent reads from the old cache object, e.g.
+  during Zope2's auto-refresh of products.
+  (https://bugs.launchpad.net/zodb/+bug/142667).
 
 
+What's new in ZODB3 3.6.3?
+==========================
+Release date: 03-Jul-2007
+
 Following is combined news from internal releases (to support ongoing
 Zope2 / Zope3 development).  These are the dates of the internal releases:
 

src/ZODB/Connection.py

@@ -961,6 +961,8 @@ class Connection(ExportImport, object):
         self._invalidated.clear()
         cache_size = self._cache.cache_size
         self._cache = cache = PickleCache(self, cache_size)
+        if getattr(self, '_reader', None) is not None:
+            self._reader._cache = cache
 
     ##########################################################################
     # Python protocol

src/ZODB/tests/testConnection.py

@@ -146,6 +146,14 @@ class ConnectionDotAdd(unittest.TestCase):
         self.datamgr.tpc_finish(self.transaction)
         self.assert_(obj._p_oid not in self.datamgr._storage._stored)
 
+    def check__resetCacheResetsReader(self):
+        # https://bugs.launchpad.net/zodb/+bug/142667
+        old_cache = self.datamgr._cache
+        self.datamgr._resetCache()
+        new_cache = self.datamgr._cache
+        self.failIf(new_cache is old_cache)
+        self.failUnless(self.datamgr._reader._cache is new_cache)
+
 class UserMethodTests(unittest.TestCase):
 
     # add isn't tested here, because there are a bunch of traditional