Merge pull request #2482 from Holzhaus/pre-commit-python

pre-commit: Add hooks for Python

.flake8

@@ -0,0 +1,5 @@
+[flake8]
+# E203 is not PEP8 compliant and is not compatible with black:
+# https://black.readthedocs.io/en/stable/the_black_code_style.html#slices
+# W503 conflicts with black, too.
+ignore = E203,W503

.pre-commit-config.yaml

@@ -78,6 +78,16 @@ repos:
     stages:
     - commit
     - manual
+-   repo: https://github.com/psf/black
+    rev: stable
+    hooks:
+    -   id: black
+        files: ^scripts/.*$
+-   repo: https://gitlab.com/pycqa/flake8
+    rev: '3.7.9'
+    hooks:
+    -   id: flake8
+        files: ^scripts/.*$
 - repo: local
   hooks:
   - id: qsscheck

pyproject.toml

@@ -0,0 +1,2 @@
+[tool.black]
+line-length = 79

scripts/audioplot.py

@@ -7,11 +7,10 @@
 
 def createSlice(columns):
     """convert an input string into a slice object"""
-    if columns == 'all':
+    if columns == "all":
         return slice(None)
-    else:
-        # creates a numpy array
-        return np.int64(columns.split(','))
+    # creates a numpy array
+    return np.int64(columns.split(","))
 
 
 def combine_files(files):
@@ -23,7 +22,7 @@ def combine_files(files):
     raw = []
     min_len = sys.maxsize  # max integer
     for fname in files:
-        raw.append(np.genfromtxt(fname, delimiter=','))
+        raw.append(np.genfromtxt(fname, delimiter=","))
         min_len = min(len(raw[-1]), min_len)
     data = raw[0][:min_len]
 
@@ -43,7 +42,7 @@ def AudioPlot(files, slice):
 
 def parseArguments():
     p = argparse.ArgumentParser(
-        prog='AudioPlot',
+        prog="AudioPlot",
         formatter_class=argparse.RawDescriptionHelpFormatter,
         description="""
 Audioplot is a simple script for drawing graphs of values. It reads a simple
@@ -60,13 +59,16 @@ def parseArguments():
 This script is useful to compare the sample files produced by the engine test
 of mixxx-test with the golden sample files.
 
-""")
-    p.add_argument('files', type=str, nargs='+', help='file to plot from')
-    p.add_argument('-c',
-                   '--columns',
-                   type=str,
-                   default='all',
-                   help='lines to plot separated by a comma, default "all"')
+""",
+    )
+    p.add_argument("files", type=str, nargs="+", help="file to plot from")
+    p.add_argument(
+        "-c",
+        "--columns",
+        type=str,
+        default="all",
+        help='lines to plot separated by a comma, default "all"',
+    )
     return p.parse_args()