GitHub Actions: Run Python 3.6 on Ubuntu 20.04

Author: cclauss

.github/workflows/test.yml

@@ -65,7 +65,7 @@ jobs:
             toxpython: 'python3.6'
             python_arch: 'x64'
             tox_env: 'py36-pytest70-xdist250-coverage62'
-            os: 'ubuntu-latest'
+            os: 'ubuntu-20.04'
           - name: 'py36-pytest70-xdist250-coverage62 (windows)'
             python: '3.6'
             toxpython: 'python3.6'

.ruff.toml

@@ -0,0 +1,26 @@
+# [tool.ruff]  # <- TODO Uncomment when migrating to pyproject.toml
+exclude = [
+    ".eggs",
+    ".tox",
+    "build",
+    "ci/templates",
+    "dist",
+]
+line-length = 140
+select = [
+    "E",
+    "F",
+    "I",
+    "PLC",
+    "PLE",
+    "UP",
+    "W",
+]
+target-version = "py37"
+
+# [tool.ruff.isort]  # <- TODO Uncomment when migrating to pyproject.toml
+[isort]
+# default-section = "THIRDPARTY"
+force-single-line = true
+forced-separate = ["test_pytest_cov"]
+known-first-party = ["pytest_cov"]

tox.ini

@@ -87,12 +87,13 @@ commands =
 
 [testenv:check]
 deps =
-    docutils
     check-manifest
+    colorama  # TODO Remove when isort > v6.0.0b2 is released.
+    docutils
     flake8
-    readme-renderer
-    pygments
     isort
+    pygments
+    readme-renderer
 skip_install = true
 usedevelop = false
 commands =