From f0d99f0ca2e7aed9b6d70132d029a48da6e90e31 Mon Sep 17 00:00:00 2001
From: Sean Dague <sean@dague.net>
Date: Thu, 27 Nov 2014 07:14:25 -0500
Subject: [PATCH] remove test.ReplaceModule from test.py

The ReplaceModule fixture is buggy and very sensitive to the sequence
things are imported in. It was only used in 3 places until the
functional test split landed (and had to be removed from there).

This removes the use of ReplaceModule for fake_ldap. Unwinding the
xenapi test code is a bit more challenging especially given how
spidery all that code is. So instead of fixing that move the
ReplaceModule into the xenapi test code where it's used and leave it
as an exercise for the xenapi folks to move to more real mocks or
monkey patching.

This gets it out of test.py so that no one else will accidentally use
it.

Change-Id: I2398a83039ef50a926c1adecbb680c935bae7ed8
---
 nova/test.py                            | 18 ------------------
 nova/tests/unit/network/test_manager.py |  4 +++-
 nova/tests/unit/virt/xenapi/stubs.py    | 23 +++++++++++++++++++++--
 3 files changed, 24 insertions(+), 21 deletions(-)

diff --git a/nova/test.py b/nova/test.py
index 45e7015715d1..904abd72fe76 100644
--- a/nova/test.py
+++ b/nova/test.py
@@ -30,7 +30,6 @@ import inspect
 import logging
 import os
 import shutil
-import sys
 import uuid
 
 import fixtures
@@ -150,23 +149,6 @@ class SampleNetworks(fixtures.Fixture):
             network.set_network_host(ctxt, net)
 
 
-class ReplaceModule(fixtures.Fixture):
-    """Replace a module with a fake module."""
-
-    def __init__(self, name, new_value):
-        self.name = name
-        self.new_value = new_value
-
-    def _restore(self, old_value):
-        sys.modules[self.name] = old_value
-
-    def setUp(self):
-        super(ReplaceModule, self).setUp()
-        old_value = sys.modules.get(self.name)
-        sys.modules[self.name] = self.new_value
-        self.addCleanup(self._restore, old_value)
-
-
 class ServiceFixture(fixtures.Fixture):
     """Run a service as a test fixture."""
 
diff --git a/nova/tests/unit/network/test_manager.py b/nova/tests/unit/network/test_manager.py
index 776160cd0c3e..eca7a663734e 100644
--- a/nova/tests/unit/network/test_manager.py
+++ b/nova/tests/unit/network/test_manager.py
@@ -3286,7 +3286,9 @@ class LdapDNSTestCase(test.TestCase):
     def setUp(self):
         super(LdapDNSTestCase, self).setUp()
 
-        self.useFixture(test.ReplaceModule('ldap', fake_ldap))
+        self.useFixture(fixtures.MonkeyPatch(
+            'nova.network.ldapdns.ldap',
+            fake_ldap))
         dns_class = 'nova.network.ldapdns.LdapDNS'
         self.driver = importutils.import_object(dns_class)
 
diff --git a/nova/tests/unit/virt/xenapi/stubs.py b/nova/tests/unit/virt/xenapi/stubs.py
index ad13ca41df85..a6395b6004be 100644
--- a/nova/tests/unit/virt/xenapi/stubs.py
+++ b/nova/tests/unit/virt/xenapi/stubs.py
@@ -15,7 +15,9 @@
 
 import pickle
 import random
+import sys
 
+import fixtures
 from oslo.serialization import jsonutils
 
 from nova import test
@@ -263,6 +265,23 @@ def stub_out_vm_methods(stubs):
     stubs.Set(vm_utils, '_wait_for_device', fake_wait_for_device)
 
 
+class ReplaceModule(fixtures.Fixture):
+    """Replace a module with a fake module."""
+
+    def __init__(self, name, new_value):
+        self.name = name
+        self.new_value = new_value
+
+    def _restore(self, old_value):
+        sys.modules[self.name] = old_value
+
+    def setUp(self):
+        super(ReplaceModule, self).setUp()
+        old_value = sys.modules.get(self.name)
+        sys.modules[self.name] = self.new_value
+        self.addCleanup(self._restore, old_value)
+
+
 class FakeSessionForVolumeTests(fake.SessionBase):
     """Stubs out a XenAPISession for Volume tests."""
     def VDI_introduce(self, _1, uuid, _2, _3, _4, _5,
@@ -354,12 +373,12 @@ class FakeSessionForFailedMigrateTests(FakeSessionForVMTests):
 class XenAPITestBase(test.TestCase):
     def setUp(self):
         super(XenAPITestBase, self).setUp()
-        self.useFixture(test.ReplaceModule('XenAPI', fake))
+        self.useFixture(ReplaceModule('XenAPI', fake))
         fake.reset()
 
 
 class XenAPITestBaseNoDB(test.NoDBTestCase):
     def setUp(self):
         super(XenAPITestBaseNoDB, self).setUp()
-        self.useFixture(test.ReplaceModule('XenAPI', fake))
+        self.useFixture(ReplaceModule('XenAPI', fake))
         fake.reset()