Formalize flake8 linting (Zulko#1439)

* Fix flake8 errors (except complexity < 10 restriction) and configure from file

* Lint tests; add 'flake8-implicit-str-concat'; add optional reqs 'lint'

* Remove blank lines at the end of 'setup.cfg'

* Refactor 'os' imports in 'tests/test_resourcerelease.py'

* Fix new flake8 errors

* Add linting and formatting instructions to README

* Fix black dep version definition in setup

* Convert relative imports into absolute ones; add relative imports linting

* Fix error in lint dependency

* Fix errors and improve flake8 config comments

* Ignores rules in 'editor.py' using configuration

* Removed uneeded '# -*- coding: utf-8 -*-' statements

* Remove '__future__' imports

* Minor changes

.github/workflows/format_check.yml

@@ -6,6 +6,7 @@ on: [push, pull_request]
 jobs:
   black:
     runs-on: ubuntu-latest
+    name: Black
     steps:
       - uses: actions/checkout@v2
       - name: Set up Python
@@ -14,6 +15,7 @@ jobs:
         uses: psf/black@stable  # already includes args "--check --diff"
   flake8:
     runs-on: ubuntu-latest
+    name: Flake8
     steps:
       - uses: actions/checkout@v2
       - name: Set up Python
@@ -23,22 +25,12 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          pip install .
-          pip install flake8
-      - name: Flake8
-        run: |
-          # stop the build if there are Python syntax errors or undefined names
-          flake8 . --count --select=E901,E999,F821,F822,F823,W605 --show-source --statistics
-          # Some warning codes are ignored because they conflict with black's formatting, or are
-          # incompatible with MoviePy's structure
-          # E203: whitespace before ':'
-          # E302: expected 2 blank lines, found 0
-          # E402: module level import not at top of file
-          # W291: trailing whitespace
-          # W293: blank line contains whitespace
-          # W503: line break before binary operator
-          flake8 moviepy --ignore=E203,E302,E402,W291,W293,W503 --max-complexity=10 --max-line-length=127 --statistics --count --exit-zero
-          # Check examples and tests with slightly relaxed rules to allow 'star' imports
-          # F403 'from moviepy import *' used; unable to detect undefined names
-          # F405 'name' may be undefined, or defined from star imports: moviepy
-          flake8 . --ignore=E203,E302,E402,W291,W293,W503,F403,F405 --exclude moviepy/ --max-complexity=10 --max-line-length=127 --statistics --count  --exit-zero
+          pip install .[lint]
+      - name: Lint examples
+        run: flake8 examples --show-source
+      - name: Lint scripts
+        run: flake8 setup.py find_latest_imagemagick_version.py docs/conf.py --show-source
+      - name: Lint tests
+        run: flake8 tests --show-source
+      - name: Lint moviepy
+        run: flake8 moviepy --show-source

README.rst

@@ -164,6 +164,28 @@ The test suite can then be executed via:
     $ pytest
 
 
+Linting and formatting
+----------------------
+
+To make sure that all the code is well formatted and consistent, we use Black_ and Flake8_. Install them by navigating to the project directory and running:
+
+.. code:: bash
+
+    $ (sudo) pip install moviepy[lint]
+
+You can lint all files running:
+
+.. code:: bash
+
+    $ flake8
+
+To format the files properly use:
+
+.. code:: bash
+
+    $ black -t py36 .
+
+
 Contribute
 ----------
 
@@ -212,6 +234,8 @@ Maintainers
 .. _ImageMagick: https://www.imagemagick.org/script/index.php
 .. _`Matplotlib`: https://matplotlib.org/
 .. _`Sphinx`: https://www.sphinx-doc.org/en/master/setuptools.html
+.. _`Black`: https://black.readthedocs.io/en/stable/
+.. _`Flake8`: https://flake8.pycqa.org/en/latest/
 
 .. People
 .. _Zulko: https://github.com/Zulko

examples/dancing_knights.py

@@ -1,5 +1,3 @@
-# -*- coding: utf-8 -*-
-
 """
 Result: https://www.youtube.com/watch?v=Qu7HJrsEYFg
 

examples/headblur.py

@@ -1,5 +1,5 @@
 from moviepy import *
-from moviepy.video.tools.tracking import manual_tracking
+from moviepy.video.tools.tracking import manual_tracking  # noqa 401
 from moviepy.video.tools.interpolators import Trajectory
 
 # LOAD THE CLIP (subclip 6'51 - 7'01 of a chaplin movie)

moviepy/Clip.py

@@ -291,7 +291,7 @@ def with_duration(self, duration, change_end=True):
             self.end = None if (duration is None) else (self.start + duration)
         else:
             if self.duration is None:
-                raise Exception("Cannot change clip start when new" "duration is None")
+                raise Exception("Cannot change clip start when new duration is None")
             self.start = self.end - duration
 
     @outplace

moviepy/audio/fx/__init__.py

@@ -1,7 +1,18 @@
 # import every video fx function
 
-from .audio_fadein import audio_fadein
-from .audio_fadeout import audio_fadeout
-from .audio_normalize import audio_normalize
-from .multiply_stereo_volume import multiply_stereo_volume
-from .multiply_volume import multiply_volume
+from moviepy.audio.fx.audio_fadein import audio_fadein
+from moviepy.audio.fx.audio_fadeout import audio_fadeout
+from moviepy.audio.fx.audio_loop import audio_loop
+from moviepy.audio.fx.audio_normalize import audio_normalize
+from moviepy.audio.fx.multiply_stereo_volume import multiply_stereo_volume
+from moviepy.audio.fx.multiply_volume import multiply_volume
+
+__all__ = (
+    "audio_fadein",
+    "audio_fadeout",
+    "audio_left_right",
+    "audio_loop",
+    "audio_normalize",
+    "multiply_stereo_volume",
+    "multiply_volume",
+)

moviepy/audio/fx/all/__init__.py

@@ -1,11 +1,11 @@
 """
-moviepy.audio.fx.all is deprecated. 
+moviepy.audio.fx.all is deprecated.
 
 Use the fx method directly from the clip instance (e.g. ``clip.audio_normalize(...)``)
-or import the function from moviepy.audio.fx instead. 
+or import the function from moviepy.audio.fx instead.
 """
 import warnings
 
-from .. import *
+from .. import *  # noqa 401,F403
 
 warnings.warn(f"\nMoviePy: {__doc__}", UserWarning)

moviepy/audio/fx/audio_loop.py

@@ -0,0 +1,26 @@
+from moviepy.audio.AudioClip import concatenate_audioclips
+from moviepy.decorators import audio_video_fx
+
+
+@audio_video_fx
+def audio_loop(clip, n_loops=None, duration=None):
+    """Loops over an audio clip.
+
+    Returns an audio clip that plays the given clip either
+    `n_loops` times, or during `duration` seconds.
+
+    Examples
+    ========
+
+    >>> from moviepy import *
+    >>> videoclip = VideoFileClip('myvideo.mp4')
+    >>> music = AudioFileClip('music.ogg')
+    >>> audio = afx.audio_loop( music, duration=videoclip.duration)
+    >>> videoclip.with_audio(audio)
+
+    """
+    if duration is not None:
+        n_loops = int(duration / clip.duration) + 1
+        return concatenate_audioclips(n_loops * [clip]).with_duration(duration)
+
+    return concatenate_audioclips(n_loops * [clip])

moviepy/audio/fx/audio_normalize.py

@@ -1,6 +1,6 @@
 from moviepy.decorators import audio_video_fx
 
-from .multiply_volume import multiply_volume
+from moviepy.audio.fx.multiply_volume import multiply_volume
 
 
 @audio_video_fx

moviepy/audio/fx/multiply_stereo_volume.py

@@ -1,5 +1,3 @@
-import numpy as np
-
 from moviepy.decorators import audio_video_fx
 
 

moviepy/audio/io/AudioFileClip.py

@@ -1,5 +1,3 @@
-from __future__ import division
-
 from moviepy.audio.AudioClip import AudioClip
 from moviepy.audio.io.readers import FFMPEG_AudioReader
 from moviepy.decorators import convert_path_to_string
@@ -43,10 +41,12 @@ class AudioFileClip(AudioClip):
     Lifetime
     --------
 
-    Note that this creates subprocesses and locks files. If you construct one of these instances, you must call
-    close() afterwards, or the subresources will not be cleaned up until the process ends.
+    Note that this creates subprocesses and locks files. If you construct one
+    of these instances, you must call close() afterwards, or the subresources
+    will not be cleaned up until the process ends.
 
-    If copies are made, and close() is called on one, it may cause methods on the other copies to fail.
+    If copies are made, and close() is called on one, it may cause methods on
+    the other copies to fail.
 
     However, coreaders must be closed separately.
 

moviepy/audio/io/ffmpeg_audiowriter.py

@@ -1,6 +1,5 @@
 import os
 import subprocess as sp
-import warnings
 
 import proglog
 

moviepy/editor.py

@@ -4,7 +4,8 @@
 
 >>> from moviepy.editor import *
 
-- Starts a pygame session to enable ``clip.show()`` and ``clip.preview()`` if pygame is installed
+- Starts a pygame session to enable ``clip.show()`` and ``clip.preview()``
+  if pygame is installed
 - Enables ``clip.ipython_display()`` if in an IPython Notebook
 - Allows the use of ``sliders`` if Matplotlib is installed
 """
@@ -16,7 +17,7 @@
 from moviepy.video.io.html_tools import ipython_display
 
 try:
-    from .video.io.sliders import sliders
+    from moviepy.video.io.sliders import sliders
 except ImportError:
 
     def sliders(*args, **kwargs):
@@ -38,7 +39,7 @@ def sliders(*args, **kwargs):
 
 # Add methods preview and show (only if pygame installed)
 try:
-    from .video.io.preview import show, preview
+    from moviepy.video.io.preview import show, preview
 except ImportError:
 
     def preview(self, *args, **kwargs):
@@ -54,7 +55,7 @@ def show(self, *args, **kwargs):
 VideoClip.show = show
 
 try:
-    from .audio.io.preview import preview
+    from moviepy.audio.io.preview import preview
 except ImportError:
 
     def preview(self, *args, **kwargs):

moviepy/tools.py

@@ -3,7 +3,6 @@
 """
 import os
 import subprocess as sp
-import sys
 import warnings
 
 import proglog

moviepy/video/VideoClip.py

@@ -227,8 +227,8 @@ def write_videofile(
           frame rate to use when generating the sound.
 
         temp_audiofile
-          the name of the temporary audiofile, as a string or path-like object, to be created and
-          then used to write the complete video, if any.
+          the name of the temporary audiofile, as a string or path-like object,
+          to be created and then used to write the complete video, if any.
 
         temp_audiofile_path
           the location that the temporary audiofile is placed, as a
@@ -709,7 +709,7 @@ def on_color(self, size=None, color=(0, 0, 0), pos=None, col_opacity=None):
           background.
 
         """
-        from .compositing.CompositeVideoClip import CompositeVideoClip
+        from moviepy.video.compositing.CompositeVideoClip import CompositeVideoClip
 
         if size is None:
             size = self.size
@@ -1312,12 +1312,12 @@ def list(arg):
 
         if arg == "font":
             # Slice removes first 8 characters: "  Font: "
-            return [l[8:] for l in lines if l.startswith("  Font:")]
+            return [line[8:] for line in lines if line.startswith("  Font:")]
         elif arg == "color":
-            # Each line is of the format "aqua  srgb(0,255,255)  SVG" so split on space and take
-            # the first item to get the color name.
+            # Each line is of the format "aqua  srgb(0,255,255)  SVG" so split
+            # on space and take the first item to get the color name.
             # The first 5 lines are header information, not colors, so ignore
-            return [l.split(" ")[0] for l in lines[5:]]
+            return [line.split(" ")[0] for line in lines[5:]]
         else:
             raise Exception("Moviepy Error: Argument must equal 'font' or 'color'")
 
@@ -1354,14 +1354,15 @@ def __init__(
         self, bitmap_frames, *, fps=None, duration=None, color_dict=None, is_mask=False
     ):
         """
-        Creates a VideoClip object from a bitmap representation. Primarily used in the test suite.
+        Creates a VideoClip object from a bitmap representation. Primarily used
+        in the test suite.
 
         Parameters
         -----------
 
         bitmap_frames
-          A list of frames. Each frame is a list of strings. Each string represents a row of colors.
-          Each color represents an (r, g, b) tuple.
+          A list of frames. Each frame is a list of strings. Each string
+          represents a row of colors. Each color represents an (r, g, b) tuple.
           Example input (2 frames, 5x3 pixel size):
           [["RRRRR",
             "RRBRR",
@@ -1371,16 +1372,18 @@ def __init__(
             "RGGGR"]]
 
         fps
-          The number of frames per second to display the clip at. `duration` will calculated from the total number of frames.
-          If both `fps` and `duration` are set, `duration` will be ignored.
+          The number of frames per second to display the clip at. `duration` will
+          calculated from the total number of frames. If both `fps` and `duration`
+          are set, `duration` will be ignored.
 
         duration
-          The total duration of the clip. `fps` will be calculated from the total number of frames.
-          If both `fps` and `duration` are set, `duration` will be ignored.
+          The total duration of the clip. `fps` will be calculated from the total
+          number of frames. If both `fps` and `duration` are set, `duration` will
+          be ignored.
 
         color_dict
-          A dictionary that can be used to set specific (r, g, b) values that correspond
-          to the letters used in ``bitmap_frames``.
+          A dictionary that can be used to set specific (r, g, b) values that
+          correspond to the letters used in ``bitmap_frames``.
           eg ``{"A": (50, 150, 150)}``.
 
           Defaults to

moviepy/video/compositing/transitions.py

@@ -7,7 +7,7 @@
 from moviepy.video.fx.fadein import fadein
 from moviepy.video.fx.fadeout import fadeout
 
-from .CompositeVideoClip import CompositeVideoClip
+from moviepy.video.compositing.CompositeVideoClip import CompositeVideoClip
 
 
 __all__ = ["crossfadein", "crossfadeout", "slide_in", "slide_out", "make_loopable"]