Update the flake8 pre-commit ignores (#2778)

* Remove additional ignores from flake8

* Remove all unused imports

* Remove all unused imports

* Update flake8 and pyupgrade

* F841, removed unused variables

* E731, removed lambda assignment to variables

* Remove E731, F403, F405, F524

* Remove E722, bare exceptions

* Remove E712, compare variable == True or == False to is True or is False

* Remove E402, module level import not at top of file

* Added --pre-file-ignores

* Add --per-file-ignores removing E741, E302 and E704

* Add E741, do not use variables named ‘l’, ‘O’, or ‘I’ to ignore issues in classic control

* Fixed issues for pytest==6.2

* Remove unnecessary # noqa

* Edit comment with the removal of E302

* Added warnings and declared module, attr for pyright type hinting

* Remove unused import

* Removed flake8 E302

* Updated flake8 from 3.9.2 to 4.0.1

* Remove unused variable

.pre-commit-config.yaml

@@ -10,12 +10,13 @@ repos:
       - id: codespell
         args:
           - --ignore-words-list=nd,reacher,thist,ths
-  - repo: https://gitlab.com/pycqa/flake8
-    rev: 3.9.2
+  - repo: https://gitlab.com/PyCQA/flake8
+    rev: 4.0.1
     hooks:
       - id: flake8
         args:
-          - --ignore=E203,E402,E712,E722,E731,E741,F401,F403,F405,F524,F841,W503,E302,E704
+          - '--per-file-ignores=*/__init__.py:F401 gym/envs/registration.py:E704'
+          - --ignore=E203,W503,E741
           - --max-complexity=30
           - --max-line-length=456
           - --show-source
@@ -26,7 +27,7 @@ repos:
       - id: isort
         args: ["--profile", "black"]
   - repo: https://github.com/asottile/pyupgrade
-    rev: v2.31.0
+    rev: v2.32.0
     hooks:
       - id: pyupgrade
         # TODO: remove `--keep-runtime-typing` option

gym/core.py

@@ -3,7 +3,6 @@ from __future__ import annotations
 from abc import abstractmethod
 from typing import Generic, Optional, SupportsFloat, Tuple, TypeVar, Union
 
-import gym
 from gym import spaces
 from gym.logger import deprecation
 from gym.utils import seeding

gym/envs/box2d/bipedal_walker.py

@@ -1,7 +1,6 @@
 __credits__ = ["Andrea PIERRÉ"]
 
 import math
-import sys
 from typing import Optional
 
 import Box2D
@@ -17,7 +16,7 @@ from Box2D.b2 import (
 
 import gym
 from gym import error, spaces
-from gym.utils import EzPickle, colorize, seeding
+from gym.utils import EzPickle
 
 FPS = 50
 SCALE = 30.0  # affects how fast-paced the game is, forces should be adjusted as well
@@ -422,9 +421,6 @@ class BipedalWalker(gym.Env, EzPickle):
         self.scroll = 0.0
         self.lidar_render = 0
 
-        W = VIEWPORT_W / SCALE
-        H = VIEWPORT_H / SCALE
-
         self._generate_terrain(self.hardcore)
         self._generate_clouds()
 

gym/envs/box2d/car_dynamics.py

@@ -9,17 +9,8 @@ Created by Oleg Klimov
 
 import math
 
-import Box2D
 import numpy as np
-from Box2D.b2 import (
-    circleShape,
-    contactListener,
-    edgeShape,
-    fixtureDef,
-    polygonShape,
-    revoluteJointDef,
-    shape,
-)
+from Box2D.b2 import fixtureDef, polygonShape, revoluteJointDef
 
 SIZE = 0.02
 ENGINE_POWER = 100000000 * SIZE * SIZE

gym/envs/box2d/car_racing.py

@@ -1,7 +1,6 @@
 __credits__ = ["Andrea PIERRÉ"]
 
 import math
-import sys
 from typing import Optional
 
 import Box2D
@@ -11,7 +10,7 @@ from Box2D.b2 import contactListener, fixtureDef, polygonShape
 import gym
 from gym import spaces
 from gym.envs.box2d.car_dynamics import Car
-from gym.utils import EzPickle, seeding
+from gym.utils import EzPickle
 
 STATE_W = 96  # less than Atari 160x192
 STATE_H = 96
@@ -700,6 +699,6 @@ if __name__ == "__main__":
                 print(f"step {steps} total_reward {total_reward:+0.2f}")
             steps += 1
             isopen = env.render()
-            if done or restart or isopen == False:
+            if done or restart or isopen is False:
                 break
     env.close()

gym/envs/box2d/lunar_lander.py

@@ -1,7 +1,6 @@
 __credits__ = ["Andrea PIERRÉ"]
 
 import math
-import sys
 from typing import Optional
 
 import Box2D
@@ -17,7 +16,7 @@ from Box2D.b2 import (
 
 import gym
 from gym import error, spaces
-from gym.utils import EzPickle, seeding
+from gym.utils import EzPickle
 
 FPS = 50
 SCALE = 30.0  # affects how fast-paced the game is, forces should be adjusted as well
@@ -713,7 +712,7 @@ def demo_heuristic_lander(env, seed=None, render=False):
 
         if render:
             still_open = env.render()
-            if still_open == False:
+            if still_open is False:
                 break
 
         if steps % 20 == 0 or done:

gym/envs/classic_control/acrobot.py

@@ -5,7 +5,6 @@ import numpy as np
 from numpy import cos, pi, sin
 
 from gym import core, spaces
-from gym.utils import seeding
 
 __copyright__ = "Copyright 2013, RLPy http://acl.mit.edu/RLPy"
 __credits__ = [

gym/envs/classic_control/cartpole.py

@@ -10,7 +10,6 @@ import numpy as np
 
 import gym
 from gym import logger, spaces
-from gym.utils import seeding
 
 
 class CartPoleEnv(gym.Env[np.ndarray, Union[int, np.ndarray]]):

gym/envs/classic_control/continuous_mountain_car.py

@@ -20,7 +20,6 @@ import numpy as np
 
 import gym
 from gym import spaces
-from gym.utils import seeding
 
 
 class Continuous_MountainCarEnv(gym.Env):

gym/envs/classic_control/mountain_car.py

@@ -9,7 +9,6 @@ import numpy as np
 
 import gym
 from gym import spaces
-from gym.utils import seeding
 
 
 class MountainCarEnv(gym.Env):

gym/envs/classic_control/pendulum.py

@@ -7,7 +7,6 @@ import numpy as np
 
 import gym
 from gym import spaces
-from gym.utils import seeding
 
 
 class PendulumEnv(gym.Env):

gym/envs/mujoco/mujoco_env.py

@@ -7,7 +7,6 @@ import numpy as np
 
 import gym
 from gym import error, spaces
-from gym.utils import seeding
 
 try:
     import mujoco_py

gym/envs/mujoco/pusher.py

@@ -1,4 +1,3 @@
-import mujoco_py
 import numpy as np
 
 from gym import utils

gym/envs/registration.py

@@ -7,6 +7,7 @@ import importlib
 import importlib.util
 import re
 import sys
+import warnings
 from dataclasses import dataclass, field
 from typing import (
     Any,
@@ -225,6 +226,7 @@ def load_env_plugins(entry_point: str = "gym.envs") -> None:
     for plugin in metadata.entry_points(group=entry_point):
         # Python 3.8 doesn't support plugin.module, plugin.attr
         # So we'll have to try and parse this ourselves
+        module, attr = None, None
         try:
             module, attr = plugin.module, plugin.attr  # type: ignore  ## error: Cannot access member "attr" for type "EntryPoint"
         except AttributeError:
@@ -232,7 +234,10 @@ def load_env_plugins(entry_point: str = "gym.envs") -> None:
                 module, attr = plugin.value.split(":", maxsplit=1)
             else:
                 module, attr = plugin.value, None
-        except:
+        except Exception as e:
+            warnings.warn(
+                f"While trying to load plugin `{plugin}` from {entry_point}, an exception occurred: {e}"
+            )
             module, attr = None, None
         finally:
             if attr is None:
@@ -264,8 +269,12 @@ def load_env_plugins(entry_point: str = "gym.envs") -> None:
 
 
 # fmt: off
+# Classic control
+# ----------------------------------------
+
+
 @overload
-def make(id: Literal["CartPole-v0", "CartPole-v1"], **kwargs) -> Env[np.ndarray, np.ndarray | int]: ...
+def make(id: Literal["CartPole-v1"], **kwargs) -> Env[np.ndarray, np.ndarray | int]: ...
 @overload
 def make(id: Literal["MountainCar-v0"], **kwargs) -> Env[np.ndarray, np.ndarray | int]: ...
 @overload
@@ -278,6 +287,7 @@ def make(id: Literal["Acrobot-v1"], **kwargs) -> Env[np.ndarray, np.ndarray | in
 # Box2d
 # ----------------------------------------
 
+
 @overload
 def make(id: Literal["LunarLander-v2", "LunarLanderContinuous-v2"], **kwargs) -> Env[np.ndarray, np.ndarray | int]: ...
 @overload
@@ -288,6 +298,7 @@ def make(id: Literal["CarRacing-v1", "CarRacingDomainRandomize-v1"], **kwargs) -
 # Toy Text
 # ----------------------------------------
 
+
 @overload
 def make(id: Literal["Blackjack-v1"], **kwargs) -> Env[np.ndarray, np.ndarray | int]: ...
 @overload
@@ -299,6 +310,8 @@ def make(id: Literal["Taxi-v3"], **kwargs) -> Env[np.ndarray, np.ndarray | int]:
 
 # Mujoco
 # ----------------------------------------
+
+
 @overload
 def make(id: Literal[
     "Reacher-v2",

gym/envs/toy_text/blackjack.py

@@ -5,7 +5,6 @@ import numpy as np
 
 import gym
 from gym import spaces
-from gym.utils import seeding
 
 
 def cmp(a, b):

gym/envs/toy_text/frozen_lake.py

@@ -242,7 +242,6 @@ class FrozenLakeEnv(Env):
 
     def _render_gui(self, desc, mode):
         import pygame
-        from pygame.constants import SRCALPHA
 
         if self.window_surface is None:
             pygame.init()

gym/error.py

@@ -1,6 +1,3 @@
-import sys
-
-
 class Error(Exception):
     pass
 
@@ -133,7 +130,7 @@ class APIError(Error):
         if http_body and hasattr(http_body, "decode"):
             try:
                 http_body = http_body.decode("utf-8")
-            except:
+            except Exception:
                 http_body = "<Could not decode body as utf-8.>"
 
         self._message = message

gym/utils/__init__.py

@@ -5,5 +5,5 @@ not intended as API functions, and will not remain stable over time.
 # These submodules should not have any import-time dependencies.
 # We want this since we use `utils` during our import-time sanity checks
 # that verify that our dependencies are actually present.
-from .colorize import colorize
-from .ezpickle import EzPickle
+from gym.utils.colorize import colorize
+from gym.utils.ezpickle import EzPickle

gym/utils/play.py

@@ -5,7 +5,6 @@ from numpy.typing import NDArray
 from pygame import Surface
 from pygame.event import Event
 
-import gym
 from gym import Env, logger
 
 try:

gym/utils/seeding.py

@@ -4,7 +4,6 @@ import struct
 from typing import Any, List, Optional, Tuple, Union
 
 import numpy as np
-from numpy.random import Generator
 
 from gym import error
 from gym.logger import deprecation

gym/vector/async_vector_env.py

@@ -14,7 +14,6 @@ from gym.error import (
     CustomSpaceError,
     NoAsyncCallError,
 )
-from gym.logger import warn
 from gym.vector.utils import (
     CloudpickleWrapper,
     clear_mpi_env_vars,
@@ -639,7 +638,7 @@ def _worker(index, env_fn, pipe, parent_pipe, shared_memory, error_queue):
         while True:
             command, data = pipe.recv()
             if command == "reset":
-                if "return_info" in data and data["return_info"] == True:
+                if "return_info" in data and data["return_info"] is True:
                     observation, info = env.reset(**data)
                     pipe.send(((observation, info), True))
                 else:
@@ -703,7 +702,7 @@ def _worker_shared_memory(index, env_fn, pipe, parent_pipe, shared_memory, error
         while True:
             command, data = pipe.recv()
             if command == "reset":
-                if "return_info" in data and data["return_info"] == True:
+                if "return_info" in data and data["return_info"] is True:
                     observation, info = env.reset(**data)
                     write_to_shared_memory(
                         observation_space, index, observation, shared_memory

gym/vector/sync_vector_env.py

@@ -3,8 +3,6 @@ from typing import List, Optional, Union
 
 import numpy as np
 
-from gym import logger
-from gym.logger import warn
 from gym.vector.utils import concatenate, create_empty_array, iterate
 from gym.vector.vector_env import VectorEnv
 
@@ -108,7 +106,7 @@ class SyncVectorEnv(VectorEnv):
                 kwargs["seed"] = single_seed
             if options is not None:
                 kwargs["options"] = options
-            if return_info == True:
+            if return_info is True:
                 kwargs["return_info"] = return_info
 
             if not return_info:

gym/vector/utils/numpy_utils.py

@@ -4,7 +4,6 @@ from functools import singledispatch
 import numpy as np
 
 from gym.spaces import Box, Dict, Discrete, MultiBinary, MultiDiscrete, Space, Tuple
-from gym.vector.utils.spaces import _BaseGymSpaces
 
 __all__ = ["concatenate", "create_empty_array"]
 

gym/vector/utils/shared_memory.py

@@ -5,10 +5,8 @@ from functools import singledispatch
 
 import numpy as np
 
-from gym import logger
 from gym.error import CustomSpaceError
-from gym.spaces import Box, Dict, Discrete, MultiBinary, MultiDiscrete, Space, Tuple
-from gym.vector.utils.spaces import _BaseGymSpaces
+from gym.spaces import Box, Dict, Discrete, MultiBinary, MultiDiscrete, Tuple
 
 __all__ = ["create_shared_memory", "read_from_shared_memory", "write_to_shared_memory"]
 

gym/vector/vector_env.py

@@ -1,8 +1,7 @@
 from typing import List, Optional, Union
 
 import gym
-from gym.logger import deprecation, warn
-from gym.spaces import Tuple
+from gym.logger import deprecation
 from gym.vector.utils.spaces import batch_space
 
 __all__ = ["VectorEnv"]

gym/wrappers/__init__.py

@@ -1,4 +1,3 @@
-from gym import error
 from gym.wrappers.atari_preprocessing import AtariPreprocessing
 from gym.wrappers.autoreset import AutoResetWrapper
 from gym.wrappers.clip_action import ClipAction

gym/wrappers/frame_stack.py

@@ -1,5 +1,4 @@
 from collections import deque
-from typing import Optional
 
 import numpy as np
 

gym/wrappers/monitoring/video_recorder.py

@@ -418,7 +418,7 @@ class ImageEncoder:
 
         try:
             self.proc.stdin.write(frame.tobytes())
-        except Exception as e:
+        except Exception:
             stdout, stderr = self.proc.communicate()
             logger.error("VideoRecorder encoder failed: %s", stderr)
 

gym/wrappers/normalize.py

@@ -1,5 +1,3 @@
-from typing import Optional
-
 import numpy as np
 
 import gym

gym/wrappers/order_enforcing.py

@@ -1,5 +1,3 @@
-from typing import Optional
-
 import gym
 
 

gym/wrappers/record_episode_statistics.py

@@ -1,6 +1,5 @@
 import time
 from collections import deque
-from typing import Optional
 
 import numpy as np
 

gym/wrappers/record_video.py

@@ -1,5 +1,5 @@
 import os
-from typing import Callable, Optional
+from typing import Callable
 
 import gym
 from gym import logger

gym/wrappers/time_aware_observation.py

@@ -1,5 +1,3 @@
-from typing import Optional
-
 import numpy as np
 
 from gym import ObservationWrapper

gym/wrappers/time_limit.py

@@ -1,5 +1,3 @@
-from typing import Optional
-
 import gym
 
 

setup.py

@@ -6,7 +6,7 @@ from setuptools import find_packages, setup
 
 # Don't import gym module here, since deps may not be installed
 sys.path.insert(0, os.path.join(os.path.dirname(__file__), "gym"))
-from version import VERSION
+from version import VERSION  # noqa:E402
 
 # Environment-specific dependencies.
 extras = {

tests/envs/spec_list.py

@@ -11,7 +11,7 @@ SKIP_MUJOCO_WARNING_MESSAGE = (
 skip_mujoco = not (os.environ.get("MUJOCO_KEY"))
 if not skip_mujoco:
     try:
-        import mujoco_py
+        import mujoco_py  # noqa:F401
     except ImportError:
         skip_mujoco = True
 
@@ -24,12 +24,12 @@ def should_skip_env_spec_for_tests(spec):
     if skip_mujoco and ep.startswith("gym.envs.mujoco"):
         return True
     try:
-        import gym.envs.atari
+        import gym.envs.atari  # noqa:F401
     except ImportError:
         if ep.startswith("gym.envs.atari"):
             return True
     try:
-        import Box2D
+        import Box2D  # noqa:F401
     except ImportError:
         if ep.startswith("gym.envs.box2d"):
             return True

tests/envs/test_action_dim_check.py

@@ -1,5 +1,3 @@
-import pickle
-
 import pytest
 
 from gym import envs

tests/envs/test_atari_legacy_env_specs.py

@@ -1,11 +1,11 @@
-import pytest
-
-pytest.importorskip("gym.envs.atari")
-
 from itertools import product
 
+import pytest
+
 from gym.envs.registration import registry
 
+pytest.importorskip("gym.envs.atari")
+
 
 def test_ale_legacy_env_specs():
     versions = ["-v0", "-v4"]

tests/envs/test_envs.py

@@ -61,7 +61,7 @@ def test_env(spec):
 @pytest.mark.parametrize("spec", spec_list, ids=[spec.id for spec in spec_list])
 def test_reset_info(spec):
 
-    with pytest.warns(None) as warnings:
+    with pytest.warns(None):
         env = spec.make()
 
     ob_space = env.observation_space
@@ -78,13 +78,12 @@ def test_reset_info(spec):
 # Run a longer rollout on some environments
 def test_random_rollout():
     for env in [envs.make("CartPole-v1"), envs.make("FrozenLake-v1")]:
-        agent = lambda ob: env.action_space.sample()
         ob = env.reset()
         for _ in range(10):
             assert env.observation_space.contains(ob)
-            a = agent(ob)
-            assert env.action_space.contains(a)
-            (ob, _reward, done, _info) = env.step(a)
+            action = env.action_space.sample()
+            assert env.action_space.contains(action)
+            (ob, _reward, done, _info) = env.step(action)
             if done:
                 break
         env.close()

tests/envs/test_frozenlake_dfs.py

@@ -1,6 +1,3 @@
-import numpy as np
-import pytest
-
 from gym.envs.toy_text.frozen_lake import generate_random_map
 
 

tests/envs/test_registration.py

@@ -2,9 +2,8 @@ import pytest
 
 import gym
 from gym import envs, error
-from gym.envs import register, registration, registry, spec
+from gym.envs import register, spec
 from gym.envs.classic_control import cartpole
-from gym.envs.registration import EnvSpec
 
 
 class ArgumentEnv(gym.Env):

tests/spaces/test_spaces.py

@@ -569,20 +569,20 @@ def test_infinite_space(space):
     # but floats are unbounded for infinite
     if np.any(space.high != 0):
         assert (
-            space.is_bounded("above") == False
+            space.is_bounded("above") is False
         ), "inf upper bound supposed to be unbounded"
     else:
         assert (
-            space.is_bounded("above") == True
+            space.is_bounded("above") is True
         ), "non-inf upper bound supposed to be bounded"
 
     if np.any(space.low != 0):
         assert (
-            space.is_bounded("below") == False
+            space.is_bounded("below") is False
         ), "inf lower bound supposed to be unbounded"
     else:
         assert (
-            space.is_bounded("below") == True
+            space.is_bounded("below") is True
         ), "non-inf lower bound supposed to be bounded"
 
     # check for dtype

tests/utils/test_play.py

@@ -67,7 +67,7 @@ def test_play_relevant_keys_no_mapping():
     env = DummyPlayEnv()
     env.spec = DummyEnvSpec("DummyPlayEnv")
 
-    with pytest.raises(MissingKeysToAction) as info:
+    with pytest.raises(MissingKeysToAction):
         PlayableGame(env)
 
 
@@ -96,18 +96,18 @@ def test_keyboard_quit_event():
     env = DummyPlayEnv()
     game = PlayableGame(env, dummy_keys_to_action())
     event = Event(pygame.KEYDOWN, {"key": pygame.K_ESCAPE})
-    assert game.running == True
+    assert game.running is True
     game.process_event(event)
-    assert game.running == False
+    assert game.running is False
 
 
 def test_pygame_quit_event():
     env = DummyPlayEnv()
     game = PlayableGame(env, dummy_keys_to_action())
     event = Event(pygame.QUIT)
-    assert game.running == True
+    assert game.running is True
     game.process_event(event)
-    assert game.running == False
+    assert game.running is False
 
 
 def test_keyboard_relevant_keydown_event():

tests/vector/test_async_vector_env.py

@@ -167,7 +167,7 @@ def test_reset_timeout_async_vector_env(shared_memory):
         try:
             env = AsyncVectorEnv(env_fns, shared_memory=shared_memory)
             env.reset_async()
-            observations = env.reset_wait(timeout=0.1)
+            env.reset_wait(timeout=0.1)
         finally:
             env.close(terminate=True)
 
@@ -178,7 +178,7 @@ def test_step_timeout_async_vector_env(shared_memory):
     with pytest.raises(TimeoutError):
         try:
             env = AsyncVectorEnv(env_fns, shared_memory=shared_memory)
-            observations = env.reset()
+            env.reset()
             env.step_async([0.1, 0.1, 0.3, 0.1])
             observations, rewards, dones, _ = env.step_wait(timeout=0.1)
         finally:
@@ -192,7 +192,7 @@ def test_reset_out_of_order_async_vector_env(shared_memory):
     with pytest.raises(NoAsyncCallError):
         try:
             env = AsyncVectorEnv(env_fns, shared_memory=shared_memory)
-            observations = env.reset_wait()
+            env.reset_wait()
         except NoAsyncCallError as exception:
             assert exception.name == "reset"
             raise
@@ -203,7 +203,7 @@ def test_reset_out_of_order_async_vector_env(shared_memory):
         try:
             env = AsyncVectorEnv(env_fns, shared_memory=shared_memory)
             actions = env.action_space.sample()
-            observations = env.reset()
+            env.reset()
             env.step_async(actions)
             env.reset_async()
         except NoAsyncCallError as exception:
@@ -248,7 +248,7 @@ def test_already_closed_async_vector_env(shared_memory):
     with pytest.raises(ClosedEnvironmentError):
         env = AsyncVectorEnv(env_fns, shared_memory=shared_memory)
         env.close()
-        observations = env.reset()
+        env.reset()
 
 
 @pytest.mark.parametrize("shared_memory", [True, False])

tests/vector/test_shared_memory.py

@@ -65,8 +65,7 @@ def test_create_shared_memory(space, expected_type, n, ctx):
             # Assert the length of the array
             assert len(lhs[:]) == n * len(rhs[:])
             # Assert the data type
-            assert type(lhs[0]) == type(rhs[0])  # noqa: E721
-
+            assert isinstance(lhs[0], type(rhs[0]))
         else:
             raise TypeError(f"Got unknown type `{type(lhs)}`.")
 
@@ -83,7 +82,7 @@ def test_create_shared_memory(space, expected_type, n, ctx):
 def test_create_shared_memory_custom_space(n, ctx, space):
     ctx = mp if (ctx is None) else mp.get_context(ctx)
     with pytest.raises(CustomSpaceError):
-        shared_memory = create_shared_memory(space, n=n, ctx=ctx)
+        create_shared_memory(space, n=n, ctx=ctx)
 
 
 @pytest.mark.parametrize(

tests/vector/test_spaces.py

@@ -5,7 +5,7 @@ import pytest
 from numpy.testing import assert_array_equal
 
 from gym import Space
-from gym.spaces import Box, Dict, Discrete, MultiDiscrete, Tuple
+from gym.spaces import Box, Dict, MultiDiscrete, Tuple
 from gym.vector.utils.spaces import batch_space, iterate
 from tests.vector.utils import CustomSpace, assert_rng_equal, custom_spaces, spaces
 

tests/vector/test_vector_env_wrapper.py

@@ -1,4 +1,3 @@
-import gym
 from gym.vector import VectorEnvWrapper, make
 
 

tests/wrappers/nested_dict_test.py

@@ -5,7 +5,7 @@ import numpy as np
 import pytest
 
 import gym
-from gym.spaces import Box, Dict, Discrete, Tuple
+from gym.spaces import Box, Dict, Tuple
 from gym.wrappers import FilterObservation, FlattenObservation
 
 

tests/wrappers/test_autoreset.py

@@ -1,4 +1,3 @@
-import types
 from typing import Optional
 from unittest.mock import MagicMock
 
@@ -23,7 +22,9 @@ class DummyResetEnv(gym.Env):
     metadata = {}
 
     def __init__(self):
-        self.action_space = gym.spaces.Box(low=np.array([-1.0]), high=np.array([1.0]))
+        self.action_space = gym.spaces.Box(
+            low=np.array([-1.0]), high=np.array([1.0]), dtype=np.float64
+        )
         self.observation_space = gym.spaces.Box(
             low=np.array([-1.0]), high=np.array([1.0])
         )
@@ -63,6 +64,7 @@ def test_autoreset_reset_info():
     obs, info = env.reset(return_info=True)
     assert ob_space.contains(obs)
     assert isinstance(info, dict)
+    env.close()
 
 
 @pytest.mark.parametrize("spec", spec_list, ids=[spec.id for spec in spec_list])
@@ -74,12 +76,10 @@ def test_make_autoreset_true(spec):
     Note: This test assumes that all first-party environments will terminate in a finite
     amount of time with random actions, which is true as of the time of adding this test.
     """
-    env = None
-    with pytest.warns(None) as warnings:
+    with pytest.warns(None):
         env = spec.make(autoreset=True)
 
-    ob_space = env.observation_space
-    obs = env.reset(seed=0)
+    env.reset(seed=0)
     env.action_space.seed(0)
 
     env.unwrapped.reset = MagicMock(side_effect=env.unwrapped.reset)
@@ -90,22 +90,23 @@ def test_make_autoreset_true(spec):
 
     assert isinstance(env, AutoResetWrapper)
     assert env.unwrapped.reset.called
+    env.close()
 
 
 @pytest.mark.parametrize("spec", spec_list, ids=[spec.id for spec in spec_list])
 def test_make_autoreset_false(spec):
-    env = None
-    with pytest.warns(None) as warnings:
+    with pytest.warns(None):
         env = spec.make(autoreset=False)
     assert not isinstance(env, AutoResetWrapper)
+    env.close()
 
 
 @pytest.mark.parametrize("spec", spec_list, ids=[spec.id for spec in spec_list])
 def test_make_autoreset_default_false(spec):
-    env = None
-    with pytest.warns(None) as warnings:
+    with pytest.warns(None):
         env = spec.make()
     assert not isinstance(env, AutoResetWrapper)
+    env.close()
 
 
 def test_autoreset_autoreset():
@@ -118,16 +119,16 @@ def test_autoreset_autoreset():
     obs, reward, done, info = env.step(action)
     assert obs == np.array([1])
     assert reward == 0
-    assert done == False
+    assert done is False
     assert info == {"count": 1}
     obs, reward, done, info = env.step(action)
     assert obs == np.array([2])
-    assert done == False
+    assert done is False
     assert reward == 0
     assert info == {"count": 2}
     obs, reward, done, info = env.step(action)
     assert obs == np.array([0])
-    assert done == True
+    assert done is True
     assert reward == 1
     assert info == {
         "count": 0,
@@ -137,10 +138,11 @@ def test_autoreset_autoreset():
     obs, reward, done, info = env.step(action)
     assert obs == np.array([1])
     assert reward == 0
-    assert done == False
+    assert done is False
     assert info == {"count": 1}
     obs, reward, done, info = env.step(action)
     assert obs == np.array([2])
     assert reward == 0
-    assert done == False
+    assert done is False
     assert info == {"count": 2}
+    env.close()

tests/wrappers/test_clip_action.py

@@ -6,9 +6,8 @@ from gym.wrappers import ClipAction
 
 def test_clip_action():
     # mountaincar: action-based rewards
-    make_env = lambda: gym.make("MountainCarContinuous-v0")
-    env = make_env()
-    wrapped_env = ClipAction(make_env())
+    env = gym.make("MountainCarContinuous-v0")
+    wrapped_env = ClipAction(gym.make("MountainCarContinuous-v0"))
 
     seed = 0
 

tests/wrappers/test_frame_stack.py

@@ -1,8 +1,5 @@
-import pytest
-
-pytest.importorskip("gym.envs.atari")
-
 import numpy as np
+import pytest
 
 import gym
 from gym.wrappers import FrameStack
@@ -13,6 +10,9 @@ except ImportError:
     lz4 = None
 
 
+pytest.importorskip("gym.envs.atari")
+
+
 @pytest.mark.parametrize("env_id", ["CartPole-v1", "Pendulum-v1", "Pong-v0"])
 @pytest.mark.parametrize("num_stack", [2, 3, 4])
 @pytest.mark.parametrize(

tests/wrappers/test_order_enforcing.py

@@ -1,6 +1,3 @@
-import numpy as np
-import pytest
-
 import gym
 from gym.wrappers import OrderEnforcing
 

tests/wrappers/test_record_episode_statistics.py

@@ -1,4 +1,3 @@
-import numpy as np
 import pytest
 
 import gym

tests/wrappers/test_record_video.py

@@ -1,15 +1,8 @@
 import os
 import shutil
 
-import numpy as np
-import pytest
-
 import gym
-from gym.wrappers import (
-    RecordEpisodeStatistics,
-    RecordVideo,
-    capped_cubic_video_schedule,
-)
+from gym.wrappers import capped_cubic_video_schedule
 
 
 def test_record_video_using_default_trigger():

tests/wrappers/test_time_limit.py

@@ -1,6 +1,3 @@
-import numpy as np
-import pytest
-
 import gym
 from gym.wrappers import TimeLimit
 

tests/wrappers/test_transform_observation.py

@@ -7,7 +7,9 @@ from gym.wrappers import TransformObservation
 
 @pytest.mark.parametrize("env_id", ["CartPole-v1", "Pendulum-v1"])
 def test_transform_observation(env_id):
-    affine_transform = lambda x: 3 * x + 2
+    def affine_transform(x):
+        return 3 * x + 2
+
     env = gym.make(env_id)
     wrapped_env = TransformObservation(
         gym.make(env_id), lambda obs: affine_transform(obs)