add black configuration

Author: KotlinIsland

.github/workflows/test.yml

@@ -86,7 +86,7 @@ jobs:
           arch: x64
           os: windows-latest
           toxenv: type
-        - name: Code style with flake8
+        - name: Formatting with Black and code style with flake8
           python: '3.7'
           arch: x64
           os: ubuntu-latest

pyproject.toml

@@ -4,3 +4,11 @@ requires = [
     "wheel >= 0.30.0",
 ]
 build-backend = "setuptools.build_meta"
+
+[tool.black]
+line-length = 99
+target-version = ['py36']
+extend-exclude = '''
+^/mypy/typeshed|
+^/test-data
+'''

runtests.py

@@ -47,6 +47,7 @@
     'self': [executable, '-m', 'mypy', '--config-file', 'mypy_self_check.ini', '-p', 'mypy'],
     # Lint
     'lint': ['flake8', '-j0'],
+    "format": ["black", "."],
     # Fast test cases only (this is the bulk of the test suite)
     'pytest-fast': ['pytest', '-q', '-k', 'not (%s)' % ' or '.join(ALL_NON_FAST)],
     # Test cases that invoke mypy (with small inputs)

setup.cfg

@@ -34,6 +34,8 @@ exclude =
 
 # Things to ignore:
 #   E128: continuation line under-indented (too noisy)
+#   E203: conflicts with black
+#   E501: conflicts with black
 #   W601: has_key() deprecated (false positives)
 #   E701: multiple statements on one line (colon) (we use this for classes with empty body)
 #   E704: multiple statements on one line (def)
@@ -44,7 +46,7 @@ exclude =
 #   B011: Don't use assert False
 #   F821: Name not defined (generates false positives with error codes)
 #   E741: Ambiguous variable name
-extend-ignore = E128,W601,E701,E704,E402,B3,B006,B007,B011,F821,E741
+extend-ignore = E128,E203,E501,W601,E701,E704,E402,B3,B006,B007,B011,F821,E741
 
 [coverage:run]
 branch = true

test-requirements.txt

@@ -1,6 +1,7 @@
 -r mypy-requirements.txt
 -r build-requirements.txt
 attrs>=18.0
+black==22.1.0
 flake8==3.9.2
 flake8-bugbear==22.3.20
 flake8-pyi>=20.5

tox.ini

@@ -44,7 +44,9 @@ parallel_show_output = True
 [testenv:lint]
 description = check the code style
 basepython = python3.7
-commands = flake8 {posargs}
+commands =
+    flake8 {posargs}
+    black --check --diff .
 
 [testenv:type]
 description = type check ourselves