Use a timeout argument in a test to avoid waiting too long when demonstrating...

Use a timeout argument in a test to avoid waiting too long when demonstrating ClientDisconnected errors

src/ZEO/ClientStorage.py

@@ -476,10 +476,12 @@ class ClientStorage(object):
 
         return buf
 
-    def history(self, oid, size=1):
+    def history(self, oid, size=1,
+                timeout=None, # for tests
+                ):
         """Storage API: return a sequence of HistoryEntry objects.
         """
-        return self._call('history', oid, size)
+        return self._call('history', oid, size, timeout=timeout)
 
     def record_iternext(self, next=None):
         """Storage API: get the next database record.

src/ZEO/tests/ConnectionTests.py

@@ -782,7 +782,8 @@ class ReconnectionTests(CommonSetupTearDown):
         self.pollDown()
 
         # Accesses should fail now
-        self.assertRaises(ClientDisconnected, self._storage.history, ZERO)
+        self.assertRaises(ClientDisconnected, self._storage.history, ZERO,
+                          timeout=1)
 
         # Restart the server, this time read-write
         self.startServer(create=0, keep=0)