Turing test as in, you wouldn't be able to tell which subject you're conversing with is an AI and which is human? An AI today could probably pass that test if you programmed it that way and prompting was required. It might need a more robust memory though. Honestly I feel like it would be obvious which is the AI because it would "outclass" the human conversation. You can try and trick them with things like looping back to previous parts of a conversation, telling them they said something they didn't, call them a liar, all sorts of things. But it'd be pretty easy now to fool most people if someone wanted to create an AI to do that, assuming it's a blind test through text with subject A and subject B on the other side of a wall or whatever. If someone online asked you to prove you're human through text, good luck.

If you mean a test whether or not the AI is conscious, I don't think that will be absolutely provable. Possibly ever, depending on definitive proof in the future. I'm of the belief that when a certain threshold of intelligence is reached, 1 or maybe 2 different senses, and total autonomy; You reach consciousness. So long as someone/something has an ability to communicate with itself through thought, and has the ability to imagine; Then it should be considered conscious.