Don't actually connect to libvirtd in unit tests.

The libvirt tests shouldn't actually be connecting to libvirtd
while running unit tests. Many of the tests were calling either
getLibVersion or getCapabilites, which would start a connection.
Fake these out so the tests can run properly without libvirtd.

Fixes bug 1157992

Change-Id: Iff1a60fc3cc912fdaf641f1f289744bcc9cc9736

nova/tests/test_libvirt.py

@@ -307,6 +307,19 @@ class LibvirtConnTestCase(test.TestCase):
 
         self.stubs.Set(libvirt_driver.disk, 'extend', fake_extend)
 
+        class FakeConn():
+            def getCapabilities(self):
+                return """<capabilities>
+                            <host><cpu><arch>x86_64</arch></cpu></host>
+                          </capabilities>"""
+
+            def getLibVersion(self):
+                return (0 * 1000 * 1000) + (9 * 1000) + 11
+
+        self.conn = FakeConn()
+        self.stubs.Set(libvirt_driver.LibvirtDriver, '_connect',
+                       lambda *a, **k: self.conn)
+
         instance_type = db.instance_type_get(self.context, 5)
         sys_meta = instance_types.save_instance_type_info({}, instance_type)
 
@@ -721,10 +734,10 @@ class LibvirtConnTestCase(test.TestCase):
         self.flags(libvirt_type="kvm",
                    libvirt_cpu_mode=None)
 
-        def get_lib_version_stub(self):
+        def get_lib_version_stub():
             return (0 * 1000 * 1000) + (9 * 1000) + 11
 
-        self.stubs.Set(libvirt.virConnect,
+        self.stubs.Set(self.conn,
                        "getLibVersion",
                        get_lib_version_stub)
         conn = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), True)
@@ -769,10 +782,10 @@ class LibvirtConnTestCase(test.TestCase):
         self.assertEquals(conf.cpu, None)
 
     def test_get_guest_cpu_config_host_passthrough_new(self):
-        def get_lib_version_stub(self):
+        def get_lib_version_stub():
             return (0 * 1000 * 1000) + (9 * 1000) + 11
 
-        self.stubs.Set(libvirt.virConnect,
+        self.stubs.Set(self.conn,
                        "getLibVersion",
                        get_lib_version_stub)
         conn = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), True)
@@ -790,10 +803,10 @@ class LibvirtConnTestCase(test.TestCase):
         self.assertEquals(conf.cpu.model, None)
 
     def test_get_guest_cpu_config_host_model_new(self):
-        def get_lib_version_stub(self):
+        def get_lib_version_stub():
             return (0 * 1000 * 1000) + (9 * 1000) + 11
 
-        self.stubs.Set(libvirt.virConnect,
+        self.stubs.Set(self.conn,
                        "getLibVersion",
                        get_lib_version_stub)
         conn = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), True)
@@ -811,10 +824,10 @@ class LibvirtConnTestCase(test.TestCase):
         self.assertEquals(conf.cpu.model, None)
 
     def test_get_guest_cpu_config_custom_new(self):
-        def get_lib_version_stub(self):
+        def get_lib_version_stub():
             return (0 * 1000 * 1000) + (9 * 1000) + 11
 
-        self.stubs.Set(libvirt.virConnect,
+        self.stubs.Set(self.conn,
                        "getLibVersion",
                        get_lib_version_stub)
         conn = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), True)
@@ -833,10 +846,11 @@ class LibvirtConnTestCase(test.TestCase):
         self.assertEquals(conf.cpu.model, "Penryn")
 
     def test_get_guest_cpu_config_host_passthrough_old(self):
-        def get_lib_version_stub(self):
+        def get_lib_version_stub():
             return (0 * 1000 * 1000) + (9 * 1000) + 7
 
-        self.stubs.Set(libvirt.virConnect, "getLibVersion",
+        self.stubs.Set(self.conn,
+                       "getLibVersion",
                        get_lib_version_stub)
         conn = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), True)
         instance_ref = db.instance_create(self.context, self.test_instance)
@@ -852,7 +866,7 @@ class LibvirtConnTestCase(test.TestCase):
                           disk_info)
 
     def test_get_guest_cpu_config_host_model_old(self):
-        def get_lib_version_stub(self):
+        def get_lib_version_stub():
             return (0 * 1000 * 1000) + (9 * 1000) + 7
 
         # Ensure we have a predictable host CPU
@@ -869,7 +883,7 @@ class LibvirtConnTestCase(test.TestCase):
             caps.host.cpu = cpu
             return caps
 
-        self.stubs.Set(libvirt.virConnect,
+        self.stubs.Set(self.conn,
                        "getLibVersion",
                        get_lib_version_stub)
         self.stubs.Set(libvirt_driver.LibvirtDriver,
@@ -894,10 +908,10 @@ class LibvirtConnTestCase(test.TestCase):
         self.assertEquals(conf.cpu.features[1].name, "ht")
 
     def test_get_guest_cpu_config_custom_old(self):
-        def get_lib_version_stub(self):
+        def get_lib_version_stub():
             return (0 * 1000 * 1000) + (9 * 1000) + 7
 
-        self.stubs.Set(libvirt.virConnect,
+        self.stubs.Set(self.conn,
                        "getLibVersion",
                        get_lib_version_stub)
         conn = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), True)
@@ -3574,7 +3588,7 @@ class LibvirtConnTestCase(test.TestCase):
         driver = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), True)
         conn = driver._conn
         self.mox.StubOutWithMock(driver, 'list_instance_ids')
-        self.mox.StubOutWithMock(conn, 'lookupByID')
+        conn.lookupByID = self.mox.CreateMockAnything()
 
         driver.list_instance_ids().AndReturn([1, 2])
         conn.lookupByID(1).AndReturn(DiagFakeDomain(None))