A self-driving car is ready for live testing under the same conditions in which it could pass a driver's test, which is the minimum standard for anyone to be allowed to drive legally on public roads.
My road test consisted of driving out of a dead mall parking lot (careful to obey the posted 15 MPH speed limit -- this is actually the hardest part of the test!) turn right onto a street, turn left onto a residential cul-de-sac, make a three-point-turn, and return to the mall parking lot.