FIX: determine Python versions from requires-python (#92)

.cspell.json

@@ -46,6 +46,7 @@
     "mhutchie",
     "noqa",
     "noreply",
+    "pyright",
     "taplo",
     "tomlkit",
     "tomllib"

.gitignore

@@ -5,3 +5,4 @@
 # Temporary files
 condaenv.*.requirements.txt
 node_modules/
+uv.lock

create-pytest-matrix/action.yml

@@ -35,12 +35,15 @@ runs:
     - uses: actions/setup-python@v5
       with:
         python-version: "3.12"
-    - id: set-matrix
+    - uses: astral-sh/setup-uv@v3
+    - env:
+        UV_SYSTEM_PYTHON: 1
+      id: set-matrix
       name: Create run matrix in JSON form
       run: |
         delimiter="$(openssl rand -hex 8)"
         echo "matrix<<${delimiter}" >> $GITHUB_OUTPUT
-        python3 $GITHUB_ACTION_PATH/main.py \
+        uv run $GITHUB_ACTION_PATH/main.py \
           '${{ inputs.coverage-python-version }}' \
           '${{ inputs.coverage-target }}' \
           '${{ inputs.macos-python-version }}' \

create-pytest-matrix/main.py

@@ -1,4 +1,10 @@
 """Print job matrix for a GitHub Actions workflow that runs `pytest`."""
+# /// script
+# dependencies = [
+#   "packaging",
+# ]
+# requires-python = ">=3.12"
+# ///
 
 from __future__ import annotations
 
@@ -7,8 +13,12 @@
 import tomllib
 from argparse import ArgumentParser
 from configparser import ConfigParser
+from dataclasses import dataclass
 from typing import TYPE_CHECKING
 
+from packaging.specifiers import SpecifierSet
+from packaging.version import Version
+
 if TYPE_CHECKING:
     from collections.abc import Sequence
 
@@ -38,7 +48,7 @@ def _format_skipped_version(skipped_python_versions: str) -> set[str] | None:
     return set(skipped_python_versions.split(" "))
 
 
-def create_job_matrix(  # noqa: C901
+def create_job_matrix(
     coverage_python_version: str,
     coverage_target: str,
     macos_python_version: str,
@@ -52,13 +62,7 @@ def create_job_matrix(  # noqa: C901
             set(supported_python_versions) - skipped_python_versions
         )
     if coverage_target:
-        if coverage_python_version not in supported_python_versions:
-            msg = (
-                f"Selected Python {coverage_python_version} for the coverage job, but"
-                " the package only supports Python"
-                f" {", ".join(supported_python_versions)}"
-            )
-            raise ValueError(msg)
+        _is_version_allowed(coverage_python_version, supported_python_versions)
         if coverage_python_version in python_versions:
             python_versions.remove(coverage_python_version)
     includes = []
@@ -81,6 +85,7 @@ def create_job_matrix(  # noqa: C901
             "runs-on": "ubuntu-24.04",
         })
     if macos_python_version:
+        _is_version_allowed(macos_python_version, supported_python_versions)
         includes.append({
             "python-version": macos_python_version,
             "runs-on": "macos-14",
@@ -96,58 +101,104 @@ def create_job_matrix(  # noqa: C901
     return matrix
 
 
+def _is_version_allowed(version: str, supported_versions: list[str]) -> None:
+    if version not in supported_versions:
+        supported_versions_str = ", ".join(supported_versions)
+        msg = f"Selected Python {version}, but the package only supports Python {supported_versions_str}"
+        raise ValueError(msg)
+
+
 PYPROJECT_TOML = "pyproject.toml"
 SETUP_CFG = "setup.cfg"
-CLASSIFIERS_ERROR_MSG = (
-    "This package does not have Python version classifiers, so cannot determine"
-    " intended Python versions. See https://pypi.org/classifiers."
-)
 VERSION_IDENTIFIER = "Programming Language :: Python :: 3."
 
 
 def get_supported_python_versions() -> list[str]:
-    classifiers = _get_classifiers()
-    return _determine_python_versions(classifiers)
+    version_info = _get_version_info()
+    return _determine_python_versions(version_info)
+
 
+@dataclass
+class VersionInfo:
+    classifiers: list[str] | None
+    requires_python: str | None
 
-def _get_classifiers() -> list[str]:
+
+def _get_version_info() -> VersionInfo:
     if os.path.exists(SETUP_CFG):
-        return __get_classifiers_from_cfg(SETUP_CFG)
+        return _get_version_info_from_cfg(SETUP_CFG)
     if os.path.exists(PYPROJECT_TOML):
-        return __get_classifiers_from_toml(PYPROJECT_TOML)
+        return _get_version_info_from_toml(PYPROJECT_TOML)
     msg = f"This project does not contain a {SETUP_CFG} or {PYPROJECT_TOML}"
     raise FileNotFoundError(msg)
 
 
-def __get_classifiers_from_cfg(path: str) -> list[str]:
+def _get_version_info_from_cfg(path: str) -> VersionInfo:
     cfg = ConfigParser()
     cfg.read(path)
-    if not cfg.has_option("metadata", "classifiers"):
-        raise ValueError(CLASSIFIERS_ERROR_MSG)
+    return VersionInfo(
+        classifiers=__get(cfg, "metadata", "classifiers", typ=list),
+        requires_python=__get(cfg, "options", "python_requires"),
+    )
+
+
+def __get[T](
+    cfg: ConfigParser, section: str, option: str, typ: type[T] = str
+) -> T | None:
+    if not cfg.has_option(section, option):
+        return None
     raw = cfg.get("metadata", "classifiers")
-    return [s.strip() for s in raw.split("\n") if s.strip()]
+    if typ is str:
+        return raw  # pyright: ignore[reportReturnType]
+    if typ is list:
+        return [s.strip() for s in raw.split("\n") if s.strip()]  # pyright: ignore[reportReturnType]
+    msg = f"Unsupported cast type: {typ}"
+    raise NotImplementedError(msg)
 
 
-def __get_classifiers_from_toml(path: str) -> list[str]:
+def _get_version_info_from_toml(path: str) -> VersionInfo:
     with open(path, "rb") as f:
         cfg = tomllib.load(f)
-    classifiers = cfg.get("project", {}).get("classifiers")
-    if classifiers is None:
-        raise ValueError(CLASSIFIERS_ERROR_MSG)
-    return classifiers
+    project_table: dict = cfg.get("project", {})
+    return VersionInfo(
+        classifiers=project_table.get("classifiers"),
+        requires_python=project_table.get("requires-python"),
+    )
+
+
+def _determine_python_versions(version_info: VersionInfo) -> list[str]:
+    supported_versions = _determine_python_versions_from_classifiers(version_info)
+    if supported_versions is not None:
+        return supported_versions
+    if version_info.requires_python is not None:
+        return __get_allowed_versions(version_info.requires_python)
+    msg = "No PyPI classifiers or minimal Python version defined"
+    raise ValueError(msg)
 
 
-def _determine_python_versions(classifiers: list[str]) -> list[str]:
-    versions = [s for s in classifiers if s.startswith(VERSION_IDENTIFIER)]
+def _determine_python_versions_from_classifiers(
+    version_info: VersionInfo,
+) -> list[str] | None:
+    if version_info.classifiers is None:
+        return None
+    versions = [s for s in version_info.classifiers if s.startswith(VERSION_IDENTIFIER)]
     if not versions:
-        msg = (
-            f"{SETUP_CFG} does not have any classifiers of the form"
-            f' "{VERSION_IDENTIFIER}*"'
-        )
-        raise ValueError(msg)
+        return None
     prefix = VERSION_IDENTIFIER[:-2]
     return [s.replace(prefix, "") for s in versions]
 
 
+def __get_allowed_versions(version_range: str) -> list[str]:
+    """Get a list of allowed versions from a version range specifier.
+
+    >>> __get_allowed_versions(">=3.9,<3.13")
+    ['3.9', '3.10', '3.11', '3.12']
+    """
+    specifier = SpecifierSet(version_range)
+    allowed_versions = [f"3.{v}" for v in range(6, 13)]
+    versions_to_check = [Version(v) for v in sorted(allowed_versions)]
+    return [str(v) for v in versions_to_check if v in specifier]
+
+
 if __name__ == "__main__":
     raise SystemExit(main())

create-python-version-matrix/action.yml

@@ -31,11 +31,14 @@ runs:
     - uses: actions/setup-python@v5
       with:
         python-version: "3.12"
-    - id: set-matrix
+    - uses: astral-sh/setup-uv@v3
+    - env:
+        UV_SYSTEM_PYTHON: 1
+      id: set-matrix
       name: Create run matrix in JSON form
       run: |
         delimiter="$(openssl rand -hex 8)"
         echo "matrix<<${delimiter}" >> $GITHUB_OUTPUT
-        python3 $GITHUB_ACTION_PATH/main.py | tee -a $GITHUB_OUTPUT
+        uv run $GITHUB_ACTION_PATH/main.py | tee -a $GITHUB_OUTPUT
         echo "${delimiter}" >> $GITHUB_OUTPUT
       shell: bash

create-python-version-matrix/main.py

@@ -1,17 +1,22 @@
 """Print job matrix for a GitHub Actions workflow that runs `pytest`."""
+# /// script
+# dependencies = [
+#   "packaging",
+# ]
+# requires-python = ">=3.12"
+# ///
 
 import json
 import os
 import tomllib
 from configparser import ConfigParser
+from dataclasses import dataclass
+
+from packaging.specifiers import SpecifierSet
+from packaging.version import Version
 
 PYPROJECT_TOML = "pyproject.toml"
 SETUP_CFG = "setup.cfg"
-
-CLASSIFIERS_ERROR_MSG = (
-    "This package does not have Python version classifiers, so cannot determine"
-    " intended Python versions. See https://pypi.org/classifiers."
-)
 VERSION_IDENTIFIER = "Programming Language :: Python :: 3."
 
 
@@ -28,48 +33,91 @@ def create_job_matrix() -> dict:
 
 
 def get_supported_python_versions() -> list[str]:
-    classifiers = _get_classifiers()
-    return _determine_python_versions(classifiers)
+    version_info = _get_version_info()
+    return _determine_python_versions(version_info)
+
 
+@dataclass
+class VersionInfo:
+    classifiers: list[str] | None
+    requires_python: str | None
 
-def _get_classifiers() -> list[str]:
+
+def _get_version_info() -> VersionInfo:
     if os.path.exists(SETUP_CFG):
-        return __get_classifiers_from_cfg(SETUP_CFG)
+        return _get_version_info_from_cfg(SETUP_CFG)
     if os.path.exists(PYPROJECT_TOML):
-        return __get_classifiers_from_toml(PYPROJECT_TOML)
+        return _get_version_info_from_toml(PYPROJECT_TOML)
     msg = f"This project does not contain a {SETUP_CFG} or {PYPROJECT_TOML}"
     raise FileNotFoundError(msg)
 
 
-def __get_classifiers_from_cfg(path: str) -> list[str]:
+def _get_version_info_from_cfg(path: str) -> VersionInfo:
     cfg = ConfigParser()
     cfg.read(path)
-    if not cfg.has_option("metadata", "classifiers"):
-        raise ValueError(CLASSIFIERS_ERROR_MSG)
+    return VersionInfo(
+        classifiers=__get(cfg, "metadata", "classifiers", typ=list),
+        requires_python=__get(cfg, "options", "python_requires"),
+    )
+
+
+def __get[T](
+    cfg: ConfigParser, section: str, option: str, typ: type[T] = str
+) -> T | None:
+    if not cfg.has_option(section, option):
+        return None
     raw = cfg.get("metadata", "classifiers")
-    return [s.strip() for s in raw.split("\n") if s.strip()]
+    if typ is str:
+        return raw  # pyright: ignore[reportReturnType]
+    if typ is list:
+        return [s.strip() for s in raw.split("\n") if s.strip()]  # pyright: ignore[reportReturnType]
+    msg = f"Unsupported cast type: {typ}"
+    raise NotImplementedError(msg)
 
 
-def __get_classifiers_from_toml(path: str) -> list[str]:
+def _get_version_info_from_toml(path: str) -> VersionInfo:
     with open(path, "rb") as f:
         cfg = tomllib.load(f)
-    classifiers = cfg.get("project", {}).get("classifiers")
-    if classifiers is None:
-        raise ValueError(CLASSIFIERS_ERROR_MSG)
-    return classifiers
-
-
-def _determine_python_versions(classifiers: list[str]) -> list[str]:
-    versions = [s for s in classifiers if s.startswith(VERSION_IDENTIFIER)]
+    project_table: dict = cfg.get("project", {})
+    return VersionInfo(
+        classifiers=project_table.get("classifiers"),
+        requires_python=project_table.get("requires-python"),
+    )
+
+
+def _determine_python_versions(version_info: VersionInfo) -> list[str]:
+    supported_versions = _determine_python_versions_from_classifiers(version_info)
+    if supported_versions is not None:
+        return supported_versions
+    if version_info.requires_python is not None:
+        return __get_allowed_versions(version_info.requires_python)
+    msg = "No PyPI classifiers or minimal Python version defined"
+    raise ValueError(msg)
+
+
+def _determine_python_versions_from_classifiers(
+    version_info: VersionInfo,
+) -> list[str] | None:
+    if version_info.classifiers is None:
+        return None
+    versions = [s for s in version_info.classifiers if s.startswith(VERSION_IDENTIFIER)]
     if not versions:
-        msg = (
-            f"{SETUP_CFG} does not have any classifiers of the form"
-            f' "{VERSION_IDENTIFIER}*"'
-        )
-        raise ValueError(msg)
+        return None
     prefix = VERSION_IDENTIFIER[:-2]
     return [s.replace(prefix, "") for s in versions]
 
 
+def __get_allowed_versions(version_range: str) -> list[str]:
+    """Get a list of allowed versions from a version range specifier.
+
+    >>> __get_allowed_versions(">=3.9,<3.13")
+    ['3.9', '3.10', '3.11', '3.12']
+    """
+    specifier = SpecifierSet(version_range)
+    allowed_versions = [f"3.{v}" for v in range(6, 13)]
+    versions_to_check = [Version(v) for v in sorted(allowed_versions)]
+    return [str(v) for v in versions_to_check if v in specifier]
+
+
 if __name__ == "__main__":
     raise SystemExit(main())

pyproject.toml

@@ -12,6 +12,7 @@ classifiers = [
     "Programming Language :: Python :: 3.12",
     "Programming Language :: Python",
 ]
+dependencies = ["packaging"]
 description = "Python scripts used by the ComPWA/actions repository"
 dynamic = ["version"]
 license = {text = "License :: OSI Approved :: MIT License"}