def test_accel_and_decel_are_mutually_exclusive():
road = Road()
for _ in range(100):
with mock.patch("random.random", return_value=1):
car1 = Car(road, position=200, init_speed=10)
car2 = Car(road, position=400)
car1.step_speed(car2)
assert car1.speed == 12 or car1.speed == 8
def test_step_speed():
road = Road()
car1 = Car(road, position=1000, init_speed=15)
car2 = Car(road, position=10)
with mock.patch("random.random", return_value=1):
car1.step_speed(car2)
assert car1.speed == 5
car1 = Car(road, position=200, init_speed=15)
car2 = Car(road, position=223) # just enough room to speed up
with mock.patch("random.random", return_value=1):
car1.step_speed(car2)
assert car1.speed == 17
car1 = Car(road, position=200, init_speed=10)
car2 = Car(road, position=400)
with mock.patch("random.random", return_value=1):
car1.step_speed(car2)
assert car1.speed == 12
