test_db_base_plugin_v2: Skip a few tests on some platforms

netaddr (and its underlying libc inet_pton) produces different
representations of IPv4-compat addresses for different platforms.

Linux:
    >>> netaddr.IPAddress("::2")
    IPAddress('::2')
    >>>

OSX:
    >>> netaddr.IPAddress("::2")
    IPAddress('::0.0.0.2')
    >>>

As our API assumes Linux's way, skip affected test cases on
the other platforms.

Conflicts:
	neutron/tests/tools.py

Related-Bug: #1484837
Change-Id: I89e1822bb92dfcf8772bba1a3edf908c89550119

neutron/tests/tools.py

@@ -13,6 +13,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import platform
 import warnings
 
 import fixtures
@@ -121,3 +122,14 @@ class UnorderedList(list):
 
     def __neq__(self, other):
         return not self == other
+
+
+def is_bsd():
+    """Return True on BSD-based systems."""
+
+    system = platform.system()
+    if system == 'Darwin':
+        return True
+    if 'bsd' in system.lower():
+        return True
+    return False

neutron/tests/unit/db/test_db_base_plugin_v2.py

@@ -23,6 +23,7 @@ from oslo_config import cfg
 from oslo_utils import importutils
 import six
 from sqlalchemy import orm
+import testtools
 from testtools import matchers
 import webob.exc
 
@@ -3414,6 +3415,7 @@ class TestSubnetsV2(NeutronDbPluginV2TestCase):
                                  ipv6_ra_mode=constants.IPV6_SLAAC,
                                  ipv6_address_mode=constants.IPV6_SLAAC)
 
+    @testtools.skipIf(tools.is_bsd(), 'bug/1484837')
     def test_create_subnet_ipv6_pd_gw_values(self):
         cidr = constants.PROVISIONAL_IPV6_PD_PREFIX
         # Gateway is last IP in IPv6 DHCPv6 Stateless subnet
@@ -3540,6 +3542,7 @@ class TestSubnetsV2(NeutronDbPluginV2TestCase):
                                  cidr=cidr, ip_version=6,
                                  allocation_pools=allocation_pools)
 
+    @testtools.skipIf(tools.is_bsd(), 'bug/1484837')
     def test_create_subnet_with_v6_pd_allocation_pool(self):
         gateway_ip = '::1'
         cidr = constants.PROVISIONAL_IPV6_PD_PREFIX