Remove flake8 upper-bound pinning and add nightly test for flake8 main

.github/workflows/test_commit.yml

@@ -1,51 +1,77 @@
 name: Test commit
 
-on: [push, pull_request, workflow_dispatch]
+on:
+  push:
+  pull_request:
+  workflow_dispatch:
+  schedule:
+    # Every day at 1 AM
+    - cron: '0 1 * * *'
+    # Every wednesday at 1 AM
+    - cron: '0 1 * * 3'
 
 jobs:
 
-  # Test on all three platforms.
-  platform:
+  # Test on all supported Python versions and platforms
+  python_platform:
+
+    name: ${{ matrix.python }} (${{ matrix.os }})
+    if: github.event_name != 'schedule' || github.event.schedule == '0 1 * * 3'
+    runs-on: ${{ matrix.os }}
+    continue-on-error: ${{ matrix.optional || false }}
 
     strategy:
-      matrix:
-        os: [windows-latest, ubuntu-latest, macos-latest]
+        matrix:
+            os: ['ubuntu-latest']
+            python: ["3.6", "3.7", "3.8", "3.9", "3.10", "3.11"]
+            include:
 
-    runs-on: ${{ matrix.os }}
+              - os: windows-latest
+                python: '3.x'
+
+              - os: macos-latest
+                python: '3.x'
+
+              - python: '3.12-dev'
+                os: ubuntu-latest
+                optional: true
 
     steps:
       - name: Check out code.
         uses: actions/checkout@v3
 
-      - name: Set up Python.
+      - name: Set up Python ${{ matrix.python }}.
         uses: actions/setup-python@v4
         with:
-            python-version: "3.10"
+            python-version: ${{ matrix.python }}
 
       - name: Install package.
         run:  pip install .[dev]
 
       - name: Run tests.
-        run: pytest
-
-
-  # Test on all supported Python versions.
-  Python:
+        run:  pytest
 
-    strategy:
-        matrix:
-            python: ["3.6", "3.7", "3.8", "3.9", "3.10", "3.11"]
+  # Test against Flake8 main
+  flake8_main:
 
+    name: Flake8 main
+    if: github.event_name != 'schedule' || github.event.schedule == '0 1 * * *'
     runs-on: ubuntu-latest
 
+    # Uncomment to prevent failure from blocking
+    # continue-on-error: True
+
     steps:
       - name: Check out code.
         uses: actions/checkout@v3
 
-      - name: Set up Python ${{ matrix.python }}.
+      - name: Set up latest stable Python.
         uses: actions/setup-python@v4
         with:
-            python-version: ${{ matrix.python }}
+            python-version: "3.x"
+
+      - name: Install flake8 main
+        run:  pip install git+https://github.com/PyCQA/flake8.git
 
       - name: Install package.
         run:  pip install .[dev]

pyproject.toml

@@ -18,7 +18,7 @@ readme = 'PyPI.md'
 dynamic = ['version', 'description']
 requires-python = '>= 3.6'
 dependencies = [
-    'Flake8 >= 5, < 7',
+    'Flake8 >= 5',
     'TOMLi; python_version < "3.11"',
     'TOMLi < 2; python_version < "3.7"',
 ]