[BUG] Minihack-MultiRoom map generation bug (map too large)

[samvelyan]

This is a migration copy of the original bug report here: facebookresearch#107.

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🐛 Bug

Using any of the Minihack-MultiRoom environments ported from Minigrid results in the level not being created because the map is too large.

To Reproduce

Create and reset the environment

import gym
import minihack
from nle import nethack

MOVE_ACTIONS = tuple(nethack.CompassDirection)
NAVIGATE_ACTIONS = MOVE_ACTIONS + (
            nethack.Command.OPEN,
            nethack.Command.KICK,
)

env = gym.make('MiniHack-MultiRoom-N6-v0, observation_keys=("pixel_crop",), actions=NAVIGATE_ACTIONS)
env.reset()

Occasionally, this error will pop up.

mylevel.des: line 29, pos 0: Map too large at (25 x 22), max is (76 x 21) at "ENDMAP"
mylevel.des: 1 errors detected for level "mylevel". No output created!

I've also come across this error too.

mylevel.des: line 30, pos 0: Map too large at (25 x 22), max is (76 x 21) at "ENDMAP"
mylevel.des: line 32, pos 12: Coordinates (7,21) out of map range!
mylevel.des: 2 errors detected for level "mylevel". No output created!