'Delete a subnet from a router interface
Verify that deleting a subnet with router-interface-delete removes
that subnet when there are multiple subnets on the interface and
removes the interface when it is the last subnet on the interface.'

def test_router_remove_ipv6_subnet_from_interface(self):

    with self.router() as r:
        with self.network() as n:
            with self.subnet(network=n, cidr='fd00::1/64', ip_version=6) as s1:
                with self.subnet(network=n, cidr='fd01::1/64', ip_version=6) as s2:
                    body = self._router_interface_action('add', r['router']['id'], s1['subnet']['id'], None)
                    self._router_interface_action('add', r['router']['id'], s2['subnet']['id'], None)
                    port = self._show('ports', body['port_id'])
                    self.assertEqual(2, len(port['port']['fixed_ips']))
                    self._router_interface_action('remove', r['router']['id'], s1['subnet']['id'], None)
                    port = self._show('ports', body['port_id'])
                    self.assertEqual(1, len(port['port']['fixed_ips']))
                    self._router_interface_action('remove', r['router']['id'], s2['subnet']['id'], None)
                    exp_code = exc.HTTPNotFound.code
                    port = self._show('ports', body['port_id'], expected_code=exp_code)
