Fix unit tests failing in some cases

TestZeroCopy used to fail when 'localhost' resolved to an ipv6
address. https://github.com/eventlet/eventlet/issues/8

Also, "test_container_sync_realms.py:TestUtils.test_os_error"
used to fail when unit tests were run as root user. This is
because despite os.chmod(), a root user still has permission
to access the file and hence OSError is not raised.

Change-Id: Ife80b203358557999734515261814ce76c0e00cd
Signed-off-by: Prashanth Pai <ppai@redhat.com>

test/unit/common/test_container_sync_realms.py

@@ -13,10 +13,12 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import errno
 import os
 import unittest
 import uuid
 
+from mock import patch
 from swift.common.container_sync_realms import ContainerSyncRealms
 from test.unit import FakeLogger, temptree
 
@@ -41,18 +43,21 @@ class TestUtils(unittest.TestCase):
         with temptree([fname], [fcontents]) as tempdir:
             logger = FakeLogger()
             fpath = os.path.join(tempdir, fname)
-            os.chmod(tempdir, 0)
-            csr = ContainerSyncRealms(fpath, logger)
-            try:
-                self.assertEqual(
-                    logger.all_log_lines(),
-                    {'error': [
-                        "Could not load '%s': [Errno 13] Permission denied: "
-                        "'%s'" % (fpath, fpath)]})
-                self.assertEqual(csr.mtime_check_interval, 300)
-                self.assertEqual(csr.realms(), [])
-            finally:
-                os.chmod(tempdir, 0700)
+
+            def _mock_getmtime(path):
+                raise OSError(errno.EACCES,
+                              os.strerror(errno.EACCES) +
+                              ": '%s'" % (fpath))
+            with patch('os.path.getmtime', _mock_getmtime):
+                csr = ContainerSyncRealms(fpath, logger)
+
+            self.assertEqual(
+                logger.all_log_lines(),
+                {'error': [
+                    "Could not load '%s': [Errno 13] Permission denied: "
+                    "'%s'" % (fpath, fpath)]})
+            self.assertEqual(csr.mtime_check_interval, 300)
+            self.assertEqual(csr.realms(), [])
 
     def test_empty(self):
         fname = 'container-sync-realms.conf'

test/unit/obj/test_server.py

@@ -4414,7 +4414,7 @@ class TestZeroCopy(unittest.TestCase):
         self.wsgi_greenlet = spawn(
             wsgi.server, listener, self.object_controller, NullLogger())
 
-        self.http_conn = httplib.HTTPConnection('localhost', port)
+        self.http_conn = httplib.HTTPConnection('127.0.0.1', port)
         self.http_conn.connect()
 
     def tearDown(self):