public void GetSetTest()
 {
     using (var mock = new FakeRedisSocket("$5\r\nhello\r\n"))
         using (var redis = new PoolRedisClient(mock, new DnsEndPoint("fakehost", 9999)))
         {
             Assert.Equal("hello", redis.GetSet("key", "new"));
             Assert.Equal("*3\r\n$6\r\nGETSET\r\n$3\r\nkey\r\n$3\r\nnew\r\n", mock.GetMessage());
         }
 }