No, we don’t yet have auto-complete. I don’t know of a hint that will enable auto-complete.
At the time when we made the decision to go with CodeMirror, it was favored over Monaco for performance and mobile support reasons. There is an auto-complete extension for CodeMirror that we’re considering adding.
You would need to change it though, as it looks pretty bad on iOS, and it is head to use on mobile.