def connect_all()

in gym-minigrid/gym_minigrid/roomgrid.py [0:0]

• 35 lines of code
• 13 McCabe index (conditional complexity)

    def connect_all(self, door_colors=COLOR_NAMES, max_itrs=5000):
        """
        Make sure that all rooms are reachable by the agent from its
        starting position
        """

        start_room = self.room_from_pos(*self.agent_pos)

        added_doors = []

        def find_reach():
            reach = set()
            stack = [start_room]
            while len(stack) > 0:
                room = stack.pop()
                if room in reach:
                    continue
                reach.add(room)
                for i in range(0, 4):
                    if room.doors[i]:
                        stack.append(room.neighbors[i])
            return reach

        num_itrs = 0

        while True:
            # This is to handle rare situations where random sampling produces
            # a level that cannot be connected, producing in an infinite loop
            if num_itrs > max_itrs:
                raise RecursionError('connect_all failed')
            num_itrs += 1

            # If all rooms are reachable, stop
            reach = find_reach()
            if len(reach) == self.num_rows * self.num_cols:
                break

            # Pick a random room and door position
            i = self._rand_int(0, self.num_cols)
            j = self._rand_int(0, self.num_rows)
            k = self._rand_int(0, 4)
            room = self.get_room(i, j)

            # If there is already a door there, skip
            if not room.door_pos[k] or room.doors[k]:
                continue

            if room.locked or room.neighbors[k].locked:
                continue

            color = self._rand_elem(door_colors)
            door, _ = self.add_door(i, j, k, color, False)
            added_doors.append(door)

        return added_doors