From 5632b8dc552be924001e3bde0127f9c9fd21f038 Mon Sep 17 00:00:00 2001
From: Sean Dague <sean@dague.net>
Date: Thu, 17 Dec 2015 11:25:37 -0500
Subject: [PATCH] introduce ``stub_out`` method to base test class

We would like to fully remove mox from the test tree. Even for tests
that don't use mox's validation, many of them are using the symbol
patching with self.stubs.Set. We can do the same thing with the
monkeypatch fixture instead.

This introduces self.stub_out to nova/test.py and an example of what a
stubs => stub_out change would look like.

The teardown function in the converted test was removed at the same
time, as those should no longer be used.

Part of bp:remove-mox

Change-Id: I5afc3a45d9ad9c629072891b52cd5625d28b99fc
---
 nova/test.py                                  | 12 ++++++++++
 .../api_sample_tests/test_services.py         | 24 ++++++++-----------
 2 files changed, 22 insertions(+), 14 deletions(-)

diff --git a/nova/test.py b/nova/test.py
index 3dbfe764872f..cffaed044e9b 100644
--- a/nova/test.py
+++ b/nova/test.py
@@ -256,6 +256,18 @@ class TestCase(testtools.TestCase):
             if key != 'id':
                 del self.__dict__[key]
 
+    def stub_out(self, old, new):
+        """Replace a function for the duration of the test.
+
+        Use the monkey patch fixture to replace a function for the
+        duration of a test. Useful when you want to provide fake
+        methods instead of mocks during testing.
+
+        This should be used instead of self.stubs.Set (which is based
+        on mox) going forward.
+        """
+        self.useFixture(fixtures.MonkeyPatch(old, new))
+
     def flags(self, **kw):
         """Override flag variables for a test."""
         group = kw.pop('group', None)
diff --git a/nova/tests/functional/api_sample_tests/test_services.py b/nova/tests/functional/api_sample_tests/test_services.py
index 15128204c3cd..a12e04b9b5a8 100644
--- a/nova/tests/functional/api_sample_tests/test_services.py
+++ b/nova/tests/functional/api_sample_tests/test_services.py
@@ -16,7 +16,6 @@
 from oslo_config import cfg
 from oslo_utils import timeutils
 
-from nova import db
 from nova.tests.functional.api_sample_tests import api_sample_base
 from nova.tests.unit.api.openstack.compute import test_services
 
@@ -44,19 +43,16 @@ class ServicesJsonTest(api_sample_base.ApiSampleTestBaseV21):
 
     def setUp(self):
         super(ServicesJsonTest, self).setUp()
-        self.stubs.Set(db, "service_get_all",
-                       test_services.fake_db_api_service_get_all)
-        self.stubs.Set(timeutils, "utcnow", test_services.fake_utcnow)
-        self.stubs.Set(timeutils, "utcnow_ts",
-                       test_services.fake_utcnow_ts)
-        self.stubs.Set(db, "service_get_by_host_and_binary",
-                       test_services.fake_service_get_by_host_binary)
-        self.stubs.Set(db, "service_update",
-                       test_services.fake_service_update)
-
-    def tearDown(self):
-        super(ServicesJsonTest, self).tearDown()
-        timeutils.clear_time_override()
+        self.stub_out("nova.db.service_get_all",
+                      test_services.fake_db_api_service_get_all)
+        self.stub_out("oslo_utils.timeutils.utcnow", test_services.fake_utcnow)
+        self.stub_out("oslo_utils.timeutils.utcnow_ts",
+                      test_services.fake_utcnow_ts)
+        self.stub_out("nova.db.service_get_by_host_and_binary",
+                      test_services.fake_service_get_by_host_binary)
+        self.stub_out("nova.db.service_update",
+                      test_services.fake_service_update)
+        self.addCleanup(timeutils.clear_time_override)
 
     def test_services_list(self):
         """Return a list of all agent builds."""