'If no servers are given, addresses are taken from the file given by the
I{resolvconf} parameter to L{client.createResolver}.'

def test_defaultServers(self):

    resolvconf = self.path()
    resolvconf.setContent('nameserver    127.1.2.3\n')
    with AlternateReactor(Clock()):
        resolver = client.createResolver(resolvconf=resolvconf.path)
    res = [r for r in resolver.resolvers if isinstance(r, client.Resolver)]
    self.assertEqual(1, len(res))
    self.assertEqual([], res[0].servers)
    self.assertEqual([('127.1.2.3', 53)], res[0].dynServers)
