Add flake8 linter and Github CI (#19)

* Cleanup code

* Add flake8 lint and github workflow

* Update build matrix

* Relax precision for python3.7

.github/PULL_REQUEST_TEMPLATE.md

@@ -24,6 +24,7 @@
 - [ ] My change requires a change to the documentation.
 - [ ] I have updated the tests accordingly (*required for a bug fix or a new feature*).
 - [ ] I have updated the documentation accordingly.
-- [ ] I have ensured `pytest` and `pytype` both pass.
+- [ ] I have checked the codestyle using `make lint`
+- [ ] I have ensured `make pytest` and `make type` both pass.
 
 <!--- This Template is an edited version of the one from https://github.com/evilsocket/pwnagotchi/ -->

.github/workflows/ci.yml

@@ -0,0 +1,43 @@
+# This workflow will install Python dependencies, run tests and lint with a variety of Python versions
+# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions
+
+name: CI
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+    # Skip CI if [ci skip] in the commit message
+    if: "! contains(toJSON(github.event.commits.*.message), '[ci skip]')"
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: [3.6, 3.7]  # 3.8 not supported yet by pytype
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v2
+      with:
+        python-version: ${{ matrix.python-version }}
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        # cpu version of pytorch
+        pip install torch==1.4.0+cpu -f https://download.pytorch.org/whl/torch_stable.html
+        pip install .[extra,tests,docs]
+        # Use headless version
+        pip install opencv-python-headless
+    - name: Type check
+      run: |
+        make type
+    - name: Lint with flake8
+      run: |
+        make lint
+    - name: Test with pytest
+      run: |
+        make pytest

CONTRIBUTING.md

@@ -99,6 +99,12 @@ Type checking with `pytype`:
 make type
 ```
 
+Codestyle check with `flake8`:
+
+```
+make lint
+```
+
 Build the documentation:
 
 ```

Makefile

@@ -6,6 +6,13 @@ pytest:
 type:
 	pytype
 
+lint:
+	# stop the build if there are Python syntax errors or undefined names
+	# see https://lintlyci.github.io/Flake8Rules/
+	flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
+	# exit-zero treats all errors as warnings.
+	flake8 . --count --exit-zero --statistics
+
 doc:
 	cd docs && make html
 
@@ -15,7 +22,7 @@ spelling:
 clean:
 	cd docs && make clean
 
-.PHONY: clean spelling doc
+.PHONY: clean spelling doc lint
 
 # Build docker images
 # If you do export RELEASE=True, it will also push them

docs/misc/changelog.rst

@@ -34,6 +34,8 @@ Others:
 - Sync ``VecEnvs`` with Stable-Baselines
 - Update requirement: ``gym>=0.17``
 - Added ``.readthedoc.yml`` file
+- Added ``flake8`` and ``make lint`` command
+- Added Github workflow
 
 Documentation:
 ^^^^^^^^^^^^^^

setup.cfg

@@ -19,3 +19,30 @@ filterwarnings =
 
 [pytype]
 inputs = stable_baselines3
+
+[flake8]
+ignore = W503,W504  # line breaks before and after binary operators
+# Ignore import not used when aliases are defined
+per-file-ignores =
+	./stable_baselines3/__init__.py:F401
+	./stable_baselines3/common/__init__.py:F401
+	./stable_baselines3/a2c/__init__.py:F401
+	./stable_baselines3/ppo/__init__.py:F401
+	./stable_baselines3/sac/__init__.py:F401
+	./stable_baselines3/td3/__init__.py:F401
+	./stable_baselines3/common/vec_env/__init__.py:F401
+exclude =
+    # No need to traverse our git directory
+    .git,
+    # There's no value in checking cache directories
+    __pycache__,
+    # Don't check the doc
+    docs/
+    # This contains our built documentation
+    build,
+    # This contains builds of flake8 that we don't want to check
+    dist
+		*.egg-info
+max-complexity = 15
+# The GitHub editor is 127 chars wide
+max-line-length = 127

setup.py

@@ -1,6 +1,4 @@
 import os
-import sys
-import subprocess
 from setuptools import setup, find_packages
 
 with open(os.path.join('stable_baselines3', 'version.txt'), 'r') as file_handler:
@@ -63,14 +61,14 @@ from stable_baselines3 import PPO
 model = PPO('MlpPolicy', 'CartPole-v1').learn(10000)
 ```
 
-"""
+"""  # noqa:E501
 
 
 setup(name='stable_baselines3',
       packages=[package for package in find_packages()
                 if package.startswith('stable_baselines3')],
       package_data={
-        'stable_baselines3': ['py.typed', 'version.txt']
+          'stable_baselines3': ['py.typed', 'version.txt']
       },
       install_requires=[
           'gym>=0.17',
@@ -84,28 +82,32 @@ setup(name='stable_baselines3',
           'matplotlib'
       ],
       extras_require={
-        'tests': [
-            'pytest',
-            'pytest-cov',
-            'pytest-env',
-            'pytest-xdist',
-            'pytype',
-        ],
-        'docs': [
-            'sphinx',
-            'sphinx-autobuild',
-            'sphinx-rtd-theme',
-            # For spelling
-            'sphinxcontrib.spelling',
-            # Type hints support
-            # 'sphinx-autodoc-typehints'
-        ],
-        'extra': [
-            # For render
-            'opencv-python',
-            # For atari games,
-            'atari_py~=0.2.0', 'pillow'
-        ]
+          'tests': [
+              # Run tests and coverage
+              'pytest',
+              'pytest-cov',
+              'pytest-env',
+              'pytest-xdist',
+              # Type check
+              'pytype',
+              # Lint code
+              'flake8>=3.8'
+          ],
+          'docs': [
+              'sphinx',
+              'sphinx-autobuild',
+              'sphinx-rtd-theme',
+              # For spelling
+              'sphinxcontrib.spelling',
+              # Type hints support
+              # 'sphinx-autodoc-typehints'
+          ],
+          'extra': [
+              # For render
+              'opencv-python',
+              # For atari games,
+              'atari_py~=0.2.0', 'pillow'
+          ]
       },
       description='Pytorch version of Stable Baselines, implementations of reinforcement learning algorithms.',
       author='Antonin Raffin',

stable_baselines3/common/cmd_util.py

@@ -4,9 +4,7 @@ from typing import Dict, Any, Optional, Callable, Type, Union
 
 import gym
 
-from stable_baselines3.common import logger
 from stable_baselines3.common.monitor import Monitor
-from stable_baselines3.common.utils import set_random_seed
 from stable_baselines3.common.atari_wrappers import AtariWrapper
 from stable_baselines3.common.vec_env import DummyVecEnv, SubprocVecEnv
 

stable_baselines3/common/identity_env.py

@@ -1,4 +1,4 @@
-from typing import List, Union, Optional
+from typing import Union, Optional
 
 import numpy as np
 from gym import Env, Space

stable_baselines3/common/noise.py

@@ -71,8 +71,8 @@ class OrnsteinUhlenbeckActionNoise(ActionNoise):
         super(OrnsteinUhlenbeckActionNoise, self).__init__()
 
     def __call__(self) -> np.ndarray:
-        noise = self.noise_prev + self._theta * (self._mu - self.noise_prev) * self._dt + \
-                self._sigma * np.sqrt(self._dt) * np.random.normal(size=self._mu.shape)
+        noise = (self.noise_prev + self._theta * (self._mu - self.noise_prev) * self._dt
+                 + self._sigma * np.sqrt(self._dt) * np.random.normal(size=self._mu.shape))
         self.noise_prev = noise
         return noise
 

stable_baselines3/common/vec_env/vec_transpose.py

@@ -6,7 +6,7 @@ from stable_baselines3.common.vec_env.base_vec_env import VecEnv, VecEnvWrapper
 from stable_baselines3.common.preprocessing import is_image_space
 
 if typing.TYPE_CHECKING:
-    from stable_baselines3.common.type_aliases import GymStepReturn
+    from stable_baselines3.common.type_aliases import GymStepReturn  # noqa: F401
 
 
 class VecTransposeImage(VecEnvWrapper):

tests/test_distributions.py

@@ -42,6 +42,7 @@ def test_squashed_gaussian(model_class):
     actions = dist.get_actions()
     assert th.max(th.abs(actions)) <= 1.0
 
+
 def test_sde_distribution():
     n_actions = 1
     deterministic_actions = th.ones(N_SAMPLES, n_actions) * 0.1
@@ -95,4 +96,4 @@ def test_categorical():
     actions = dist.get_actions()
     entropy = dist.entropy()
     log_prob = dist.log_prob(actions)
-    assert th.allclose(entropy.mean(), -log_prob.mean(), rtol=1e-4)
+    assert th.allclose(entropy.mean(), -log_prob.mean(), rtol=2e-4)

tests/test_envs.py

@@ -46,6 +46,7 @@ def test_high_dimension_action_space():
     env = FakeImageEnv()
     # Patch the action space
     env.action_space = spaces.Box(low=-1, high=1, shape=(20,), dtype=np.float32)
+
     # Patch to avoid error
     def patched_step(_action):
         return env.observation_space.sample(), 0.0, False, {}

tests/test_save_load.py

@@ -230,7 +230,6 @@ def test_save_load_policy(model_class, policy_str):
 
     del policy, actor
 
-
     policy = policy_class.load("./logs/policy.pkl")
     if actor_class is not None:
         actor = actor_class.load("./logs/actor.pkl")

tests/test_utils.py

@@ -37,7 +37,7 @@ def test_make_vec_env(env_id, n_envs, vec_env_cls, wrapper_class):
 @pytest.mark.parametrize("env_id", ['BreakoutNoFrameskip-v4'])
 @pytest.mark.parametrize("n_envs", [1, 2])
 @pytest.mark.parametrize("wrapper_kwargs", [None, dict(clip_reward=False, screen_size=60)])
-def test_make_vec_env(env_id, n_envs, wrapper_kwargs):
+def test_make_atari_env(env_id, n_envs, wrapper_kwargs):
     env_id = 'BreakoutNoFrameskip-v4'
     env = make_atari_env(env_id, n_envs,
                          wrapper_kwargs=wrapper_kwargs, monitor_dir=None, seed=0)
@@ -55,15 +55,14 @@ def test_make_vec_env(env_id, n_envs, wrapper_kwargs):
     if wrapper_kwargs is not None:
         assert obs.shape == (n_envs, 60, 60, 1)
         assert wrapped_atari_env.observation_space.shape == (60, 60, 1)
-        assert wrapped_atari_env.clip_reward == False
+        assert wrapped_atari_env.clip_reward is False
     else:
         assert obs.shape == (n_envs, 84, 84, 1)
         assert wrapped_atari_env.observation_space.shape == (84, 84, 1)
-        assert wrapped_atari_env.clip_reward == True
+        assert wrapped_atari_env.clip_reward is True
         assert np.max(np.abs(reward)) < 1.0
 
 
-
 def test_custom_vec_env(tmp_path):
     """
     Stand alone test for a special case (passing a custom VecEnv class) to avoid doubling the number of tests.
@@ -73,7 +72,6 @@ def test_custom_vec_env(tmp_path):
                        monitor_dir=monitor_dir, seed=0,
                        vec_env_cls=SubprocVecEnv, vec_env_kwargs={'start_method': None})
 
-
     assert env.num_envs == 1
     assert isinstance(env, SubprocVecEnv)
     assert os.path.isdir(monitor_dir)

tests/test_vec_check_nan.py

@@ -68,5 +68,4 @@ def test_check_nan():
     else:
         assert False
 
-
     env.step(np.array([[0, 1], [0, 1]]))

tests/test_vec_normalize.py

@@ -3,7 +3,8 @@ import pytest
 import numpy as np
 
 from stable_baselines3.common.running_mean_std import RunningMeanStd
-from stable_baselines3.common.vec_env import DummyVecEnv, VecNormalize, VecFrameStack, sync_envs_normalization, unwrap_vec_normalize
+from stable_baselines3.common.vec_env import (DummyVecEnv, VecNormalize, VecFrameStack, sync_envs_normalization,
+                                              unwrap_vec_normalize)
 from stable_baselines3 import SAC, TD3
 
 ENV_ID = 'Pendulum-v0'
@@ -53,8 +54,8 @@ def _make_warmstart_cartpole():
 def test_runningmeanstd():
     """Test RunningMeanStd object"""
     for (x_1, x_2, x_3) in [
-        (np.random.randn(3), np.random.randn(4), np.random.randn(5)),
-        (np.random.randn(3, 2), np.random.randn(4, 2), np.random.randn(5, 2))]:
+            (np.random.randn(3), np.random.randn(4), np.random.randn(5)),
+            (np.random.randn(3, 2), np.random.randn(4, 2), np.random.randn(5, 2))]:
         rms = RunningMeanStd(epsilon=0.0, shape=x_1.shape[1:])
 
         x_cat = np.concatenate([x_1, x_2, x_3], axis=0)