fix test_cancel

tests/test_cancel.py

@@ -1,5 +1,3 @@
-from unittest import skip
-
 from .dispersytestclass import DispersyTestFunc
 from ..util import blocking_call_on_reactor_thread
 
@@ -80,17 +78,22 @@ def create_cancel():
         cancel1 = node.call(create_cancel)
         self.assertIsNotNone(cancel1.packet)
 
+        self._logger.debug(u"!!!! second time")
         self.assertRaises(RuntimeError, create_cancel)
 
-    @skip("Will change this test to a meaningful one")
     def test_node_resolve_cancel_twice(self):
         """
-        Make sure that in the event of receiving two cancel messages from the same member, both will be stored,
-        and in case of receiving a lower one, that we will send the higher one back to the sender.
+        If we receive two cancel messages canceling the same message, the higher one should be stored as the
+        latest cancel messages.
+
+        The latest cancel message is the one that has the highest (global_time, mid) combination.
 
-        MM gives NODE permission to cancel, NODE generates a message and then cancels it twice.
-        Both messages should be kept and the lowest one should be canceled.
+        In this test, we first same the original message C0, then we send the higher cancel message C2,
+        and finally the lower cancel message C1.
 
+        The receiver first updates its database with C2 as the latest cancel message of C0.
+        When it receives C1, it will recognise that it has C2 > C1, and it sends C2 to the sender
+        to inform him with the latest cancel message of C0.
         """
         node, other = self.create_nodes(2)
         node.send_identity(other)
@@ -108,12 +111,9 @@ def test_node_resolve_cancel_twice(self):
         cancel1 = node.create_cancel_own(message, 11)
         cancel2 = node.create_cancel_own(message, 12)
         low_message, high_message = sorted([cancel1, cancel2], key=lambda msg: msg.packet)
-        self._logger.debug("!!! give message")
         other.give_message(message, node)
-        self._logger.debug("!!! give low_message")
-        other.give_message(low_message, node)
-        self._logger.debug("!!! give high_message")
         other.give_message(high_message, node)
+        other.give_message(low_message, node)
         # OTHER should send the first message back when receiving
         # the second one (its "higher" than the one just received)
         cancel_packets = list()
@@ -136,17 +136,16 @@ def fetch_all_messages():
                 self._logger.debug("_______ %s", row)
         other.call(fetch_all_messages)
 
-        self._logger.debug("%d", len(low_message.packet))
+        self._logger.debug("%d", len(high_message.packet))
 
-        self.assertEqual(len(cancel_packets), len([low_message.packet]))
+        self.assertEqual(len(cancel_packets), len([high_message.packet]))
 
         # NODE should have both messages on the database and the lowest one should be undone by the highest.
         messages = other.fetch_messages((u"dispersy-cancel-own",))
         self.assertEquals(len(messages), 2)
-        other.assert_is_done(low_message)
-        other.assert_is_canceled(high_message)
-        other.assert_is_canceled(high_message, canceled_by=low_message)
-        other.assert_is_canceled(message, canceled_by=low_message)
+        other.assert_is_stored(low_message)
+        other.assert_is_stored(high_message)
+        other.assert_is_canceled(message, canceled_by=high_message)
 
     def test_missing_message(self):
         """
@@ -170,7 +169,7 @@ def test_missing_message(self):
 
         # receive the dispersy-missing-message messages
         global_times = [message.distribution.global_time for message in messages]
-        global_time_requests = []
+        global_time_requests = list()
 
         for _, message in node.receive_messages(names=[u"dispersy-missing-message"]):
             self.assertEqual(message.payload.member.public_key, node.my_member.public_key)
@@ -187,8 +186,8 @@ def test_missing_message(self):
 
     def test_revoke_causing_cancel(self):
         """
-        SELF gives NODE permission to cancel, OTHER created a message, NODE cancels the message, SELF
-        revokes the cancel permission AFTER the message was canceled -> the message is not re-done.
+        SELF gives NODE permission to cancel, OTHER created a message M1, NODE cancels the message with C1, SELF
+        revokes the cancel permission AFTER the message was canceled -> the message is not resumed.
         """
         node, other = self.create_nodes(2)
         node.send_identity(other)
@@ -207,11 +206,11 @@ def test_revoke_causing_cancel(self):
         # NODE cancels the message
         cancel = node.create_cancel_other(message, message.distribution.global_time + 1)
         other.give_message(cancel, node)
-        other.assert_is_canceled(message)
+        other.assert_is_canceled(message, canceled_by=cancel)
         other.assert_is_stored(cancel)
 
         # SELF revoke cancel permission from NODE
         revoke = self._mm.create_revoke([(node.my_member, self._community.get_meta_message(u"full-sync-text"),
                                           u"cancel")])
         other.give_message(revoke, self._mm)
-        other.assert_is_canceled(message)
+        other.assert_is_canceled(message, canceled_by=cancel)