def test_taking_actions(): """Does the environment correctly change the state when told to take an action with and without stochasticity?""" random.seed() env = Gridworld(4, 4, 0.0) # Deterministic tests assert env.next_state(env.initial_state(), Action.up) == env.state_from_grid_position(GridPosition(0, 1)) assert env.next_state(env.initial_state(), Action.down) == env.state_from_grid_position(GridPosition(0, 0)) assert env.next_state(env.initial_state(), Action.left) == env.state_from_grid_position(GridPosition(0, 0)) assert env.next_state(env.initial_state(), Action.right) == env.state_from_grid_position(GridPosition(1, 0)) # Stochastic tests env.failure_rate = 0.1 assert ratio_test(lambda state: state == env.state_from_grid_position(GridPosition(0, 0)), partial(env.next_state, env.initial_state(), Action.left), 10000) == 1.0 ratio = ratio_test(lambda state: state == env.state_from_grid_position(GridPosition(0, 0)), partial(env.next_state, env.initial_state(), Action.up), 10000) assert 0.09 < ratio < 0.11
def test_termination(): """Does the environment terminate in the correct state?""" env = Gridworld(4, 4, 0) assert not env.is_terminal(env.state_from_grid_position(GridPosition(0, 0))) assert env.is_terminal(env.state_from_grid_position(GridPosition(3, 3)))