Fix compatibility with Python 3.9

.github/workflows/linting.yaml

@@ -3,12 +3,12 @@ name: linting
 on:
   push:
     branches:
-      - devel
       - master
+      - stable
   pull_request:
     branches:
-      - devel
       - master
+      - stable
 
 jobs:
   setup:
@@ -23,6 +23,9 @@ jobs:
         if: steps.cache.outputs.cache-hit != 'true'
         uses: actions/setup-python@v4
         with:
+          # TODO: Remove explicit Python version once bug with .python-version file is solved
+          #       https://github.com/actions/setup-python/issues/734
+          python-version: '3.11'
           cache: 'poetry'
       - name: Install dependencies
         if: steps.python.outputs.cache-hit != 'true'
@@ -41,6 +44,9 @@ jobs:
         id: python
         uses: actions/setup-python@v4
         with:
+          # TODO: Remove explicit Python version once bug with .python-version file is solved
+          #       https://github.com/actions/setup-python/issues/734
+          python-version: '3.11'
           cache: 'poetry'
       - name: Install dependencies
         run: |

.github/workflows/testing.yaml

@@ -3,16 +3,20 @@ name: testing
 on:
   push:
     branches:
-      - devel
       - master
+      - stable
   pull_request:
     branches:
-      - devel
       - master
+      - stable
 
 jobs:
   setup:
     runs-on: ubuntu-22.04
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ['3.9', '3.10', '3.11']
     steps:
       - uses: actions/checkout@v3
       - name: Install poetry
@@ -23,6 +27,7 @@ jobs:
         if: steps.cache.outputs.cache-hit != 'true'
         uses: actions/setup-python@v4
         with:
+          python-version: ${{ matrix.python-version }}
           cache: 'poetry'
       - name: Install dependencies
         if: steps.python.outputs.cache-hit != 'true'
@@ -32,6 +37,10 @@ jobs:
   test:
     needs: setup
     runs-on: ubuntu-22.04
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ['3.9', '3.10', '3.11']
     steps:
       - uses: actions/checkout@v3
       - name: Install poetry
@@ -41,6 +50,7 @@ jobs:
         id: python
         uses: actions/setup-python@v4
         with:
+          python-version: ${{ matrix.python-version }}
           cache: 'poetry'
       - name: Install package
         run: |

.gitignore

@@ -1,5 +1,6 @@
-# dependencies
+# environments
 .venv/
+.tox/
 
 # packaging
 dist/

.python-version

@@ -1 +1,3 @@
 3.11
+3.10
+3.9

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## v1.3.0 (unreleased)
 
 - Added support for `.header.yml` config files.
+- Fixed compatibility with Python 3.9.
 
 ## v1.2.0
 

Makefile

@@ -15,7 +15,7 @@ unbehead:
 	unbehead --check
 
 .PHONY: lint
-lint: mypy ruff unbehead
+lint: ruff unbehead mypy
 
 # -- testing -------------------------------------------------------------------
 

README.md

@@ -131,7 +131,7 @@ git clone https://github.com/unconventionaldotdev/unbeheader
 cd unbeheader
 ```
 
-Before creating the virtualenv, you probably want to be using the same version of Python that the development of the project is targeting. This is the version specified in the `.python-version` file and you can install it with `pyenv`:
+Before creating the virtualenv, you probably want to be using the same version of Python that the development of the project is targeting. This is the first version specified in the `.python-version` file and you can install it with `pyenv`:
 
 ```sh
 pyenv install
@@ -160,14 +160,20 @@ unbehead
 
 This project uses GitHub Actions to run the tests and linter on every pull request to the `master` and `devel` branches. You are still encouraged to run the tests and linter locally before pushing your changes.
 
+Linter checks can be run with:
+
+```sh
+poetry run -- make lint
+```
+
 Tests can be run with:
 
 ```sh
 poetry run -- make test
 ```
 
-Linter can be run with:
+Tests can be run against all supported Python versions with:
 
 ```sh
-poetry run -- make lint
+tox
 ```

pyproject.toml

@@ -1,6 +1,7 @@
 [virtualenvs]
 create = true
 in-project = true
+prefer-active-python = true
 
 [tool.poetry]
 name = "unbeheader"
@@ -37,6 +38,7 @@ click = ">=8"
 mypy = "^1.5.1"
 pytest = "^7.4.0"
 ruff = "^0.0.280"
+tox = "^4.11.3"
 types-pyyaml = "^6.0.12.11"
 
 [build-system]

src/unbeheader/typing.py

@@ -6,10 +6,10 @@
 from re import Pattern
 from typing import Any
 from typing import NamedTuple
-from typing import TypeAlias
 
-ConfigDict: TypeAlias = dict[str, Any]
-PathCache: TypeAlias = dict[Path, bool]
+# TODO: Use explicit TypeAlias when Python 3.9 is dropped
+ConfigDict = dict[str, Any]
+PathCache = dict[Path, bool]
 
 
 @dataclass

src/unbeheader/util.py

@@ -1,6 +1,8 @@
 # This file is part of Unbeheader.
 # Copyright (C) CERN & UNCONVENTIONAL
 
+from __future__ import annotations
+
 import re
 from pathlib import Path
 from re import Match

tox.ini

@@ -0,0 +1,10 @@
+[tox]
+envlist = py{39,310,311}
+no_package = true
+
+[testenv]
+allowlist_externals = poetry
+commands_pre =
+    poetry install -v
+commands =
+    poetry run -- make test