tests: make Patch usable as a context manager

neo/tests/__init__.py

@@ -26,6 +26,7 @@ import unittest
 import MySQLdb
 import transaction
 
+from functools import wraps
 from mock import Mock
 from neo.lib import debug, logging, protocol
 from neo.lib.protocol import NodeTypes, Packets, UUID_NAMESPACES
@@ -47,7 +48,7 @@ def expectedFailure(exception=AssertionError):
                 # XXX: passing sys.exc_info() causes deadlocks
                 raise _ExpectedFailure((type(e), None, None))
             raise _UnexpectedSuccess
-        return functools.wraps(func)(wrapper)
+        return wraps(func)(wrapper)
     if callable(exception) and not isinstance(exception, type):
         func = exception
         exception = Exception
@@ -514,6 +515,45 @@ class NeoUnitTestBase(NeoTestBase):
     def checkAnswerObjectPresent(self, conn, **kw):
         return self.checkAnswerPacket(conn, Packets.AnswerObjectPresent, **kw)
 
+
+class Patch(object):
+
+    applied = False
+
+    def __init__(self, patched, **patch):
+        (name, patch), = patch.iteritems()
+        wrapped = getattr(patched, name)
+        wrapper = lambda *args, **kw: patch(wrapped, *args, **kw)
+        self._patched = patched
+        self._name = name
+        self._wrapper = wraps(wrapped)(wrapper)
+        try:
+            orig = patched.__dict__[name]
+            self._revert = lambda: setattr(patched, name, orig)
+        except KeyError:
+            self._revert = lambda: delattr(patched, name)
+
+    def apply(self):
+        assert not self.applied
+        setattr(self._patched, self._name, self._wrapper)
+        self.applied = True
+
+    def revert(self):
+        del self.applied
+        self._revert()
+
+    def __del__(self):
+        if self.applied:
+            self.revert()
+
+    def __enter__(self):
+        self.apply()
+        return self
+
+    def __exit__(self, t, v, tb):
+        self.__del__()
+
+
 connector_cpt = 0
 
 class DoNothingConnector(Mock):

neo/tests/threaded/__init__.py

@@ -36,7 +36,7 @@ from neo.lib.connector import SocketConnector, \
 from neo.lib.event import EventManager
 from neo.lib.protocol import CellStates, ClusterStates, NodeStates, NodeTypes
 from neo.lib.util import SOCKET_CONNECTORS_DICT, parseMasterList, p64
-from .. import NeoTestBase, getTempDirectory, setupMySQLdb, \
+from .. import NeoTestBase, Patch, getTempDirectory, setupMySQLdb, \
     ADDRESS_TYPE, IP_VERSION_FORMAT_DICT, DB_PREFIX, DB_USER
 
 BIND = IP_VERSION_FORMAT_DICT[ADDRESS_TYPE], 0
@@ -386,23 +386,6 @@ class LoggerThreadName(str):
             return str.__str__(self)
 
 
-class Patch(object):
-
-    def __init__(self, patched, **patch):
-        (name, patch), = patch.iteritems()
-        wrapped = getattr(patched, name)
-        wrapper = lambda *args, **kw: patch(wrapped, *args, **kw)
-        orig = patched.__dict__.get(name)
-        setattr(patched, name, wraps(wrapped)(wrapper))
-        if orig is None:
-            self._revert = lambda: delattr(patched, name)
-        else:
-            self._revert = lambda: setattr(patched, name, orig)
-
-    def __del__(self):
-        self._revert()
-
-
 class ConnectionFilter(object):
 
     filtered_count = 0
@@ -469,6 +452,8 @@ class ConnectionFilter(object):
     def add(self, filter, *patches):
         with self.lock:
             self.filter_dict[filter] = patches
+            for p in patches:
+                p.apply()
 
     def remove(self, *filters):
         with self.lock:

neo/tests/threaded/test.py

@@ -28,8 +28,8 @@ from neo.storage.transactions import TransactionManager, \
 from neo.lib.connection import ConnectionClosed, MTClientConnection
 from neo.lib.protocol import CellStates, ClusterStates, NodeStates, Packets, \
     ZERO_TID
-from .. import expectedFailure, _UnexpectedSuccess
-from . import ClientApplication, NEOCluster, NEOThreadedTest, Patch
+from .. import expectedFailure, _UnexpectedSuccess, Patch
+from . import ClientApplication, NEOCluster, NEOThreadedTest
 from neo.lib.util import add64, makeChecksum
 from neo.client.exception import NEOStorageError
 from neo.client.pool import CELL_CONNECTED, CELL_GOOD
@@ -271,14 +271,11 @@ class Test(NEOThreadedTest):
             o1.value += 1
             o2.value += 2
 
-            p = (Patch(TransactionManager, storeObject=onStoreObject),
-                 Patch(MTClientConnection, ask=onAsk))
-            try:
+            with Patch(TransactionManager, storeObject=onStoreObject), \
+                 Patch(MTClientConnection, ask=onAsk):
                 t = self.newThread(t1.commit)
                 t2.commit()
                 t.join()
-            finally:
-                del p
             t1.begin()
             t2.begin()
             self.assertEqual(o1.value, 3)
@@ -578,6 +575,7 @@ class Test(NEOThreadedTest):
             x2 = c2.root()['x']
             p = Patch(cluster.client, _handlePacket=_handlePacket)
             try:
+                p.apply()
                 t = self.newThread(t1.commit)
                 l1.acquire()
                 t2.begin()
@@ -649,6 +647,7 @@ class Test(NEOThreadedTest):
             cache._remove(cache._oid_dict[x2._p_oid].pop())
             p = Patch(cluster.client, _loadFromStorage=_loadFromStorage)
             try:
+                p.apply()
                 t = self.newThread(x2._p_activate)
                 l1.acquire()
                 # At this point, x could not be found the cache and the result
@@ -685,6 +684,7 @@ class Test(NEOThreadedTest):
             t1.abort()
             p = Patch(c1, _flush_invalidations=_flush_invalidations)
             try:
+                p.apply()
                 t = self.newThread(t1.begin)
                 l1.acquire()
                 cluster.client.setPoll(0)
@@ -745,9 +745,8 @@ class Test(NEOThreadedTest):
             cluster.client.setPoll(1)
 
             # Check reconnection to storage.
-            p = Patch(cluster.client.cp, getConnForNode=getConnForNode)
-            self.assertFalse(cluster.client.history(x1._p_oid))
-            del p
+            with Patch(cluster.client.cp, getConnForNode=getConnForNode):
+                self.assertFalse(cluster.client.history(x1._p_oid))
             self.assertFalse(conn)
             self.assertTrue(cluster.client.history(x1._p_oid))
 
@@ -831,6 +830,7 @@ class Test(NEOThreadedTest):
                                            master_nodes=cluster.master_nodes)
                 p = Patch(client.storage_bootstrap_handler, notReady=notReady)
                 try:
+                    p.apply()
                     client.setPoll(1)
                     x = client.load(ZERO_TID)
                 finally:

neo/tests/threaded/testReplication.py

@@ -25,7 +25,8 @@ from neo.lib.connection import ClientConnection
 from neo.lib.protocol import CellStates, ClusterStates, Packets, \
     ZERO_OID, ZERO_TID, MAX_TID, uuid_str
 from neo.lib.util import p64
-from . import ConnectionFilter, NEOCluster, NEOThreadedTest, Patch, \
+from .. import Patch
+from . import ConnectionFilter, NEOCluster, NEOThreadedTest, \
     predictable_random, Serialized
 
 
@@ -225,10 +226,8 @@ class ReplicationTests(NEOThreadedTest):
                         # a second replication partially and aborts.
                         p = Patch(backup.storage_list[storage].replicator,
                                   fetchObjects=fetchObjects)
-                    try:
+                    with p:
                         importZODB(lambda x: counts[0] > 1)
-                    finally:
-                        del p
                     upstream.client.setPoll(0)
                     if event > 5:
                         backup.neoctl.checkReplicas(check_dict, ZERO_TID, None)
@@ -274,8 +273,7 @@ class ReplicationTests(NEOThreadedTest):
         def __init__(orig, *args, **kw):
             count[0] += 1
             orig(*args, **kw)
-        p = Patch(ClientConnection, __init__=__init__)
-        try:
+        with Patch(ClientConnection, __init__=__init__):
             upstream.storage.listening_conn.close()
             Serialized.tic(); self.assertEqual(count[0], 0)
             Serialized.tic(); count[0] or Serialized.tic()
@@ -284,8 +282,6 @@ class ReplicationTests(NEOThreadedTest):
             time.sleep(1.1)
             Serialized.tic(); self.assertEqual(count[0], 3)
             Serialized.tic(); self.assertEqual(count[0], 3)
-        finally:
-            del p
 
     @backup_test()
     def testBackupDelayedUnlockTransaction(self, backup):