'As part of its constructor, C{StubResolver} opens C{/etc/resolv.conf};
then, explicitly closes it and does not count on the GC to do so for
it.'

def test_closesResolvConf(self):

    handle = FilePath(self.mktemp())
    resolvConf = handle.open(mode='w+')
    class StubResolver(client.Resolver, ):
        def _openFile(self, name):
            return resolvConf
    StubResolver(servers=['example.com', 53], resolv='/etc/resolv.conf', reactor=Clock())
    self.assertTrue(resolvConf.closed)
