That's the thing I always think about with these "self-driving" cars, is when there is snow and it can't see where the lines or curbs or whatever are, or night/rain/etc.
I actually watched a PBS show some years ago where they were at a lab where they were testing the software for (real) self-driving cars, and how we sell ourselves short as far as the processing required for a lot of driving tasks. They had (manually) driven a car around Boston with all the cameras etc. that a self-driving car would have, then they took all that input back to the lab to see how the software would process it.
One of the things that was really hard for the software to process was how to make a left turn through oncoming traffic, the calculation that we humans make (mostly successfully) to decide if there is enough room/time to make the turn based on the gap and speed of the oncoming traffic was very difficult for the software.
Also there was a pizza delivery guy on the side of the street, taking pizza boxes out of the back of a minivan or SUV, the software identified the vehicle on the side of the road, identified the driver as someone who might cross, but then he hoisted the pizza boxes onto his shoulder, which changed his silhouette, and the software no longer recognized him as a human, and would not have stopped if he had crossed the road in front of the car.