feat: add Python 3.11 support

Read the Python support from the .python-version file to keep a single
source of truth.

riotfile.py

@@ -2,7 +2,12 @@
 from riot import latest
 
 
-SUPPORTED_PYTHON_VERSIONS = ["2.7", "3.5", "3.6", "3.7", "3.8", "3.9", "3.10"]
+with open("tests/.python-version", "r") as f:
+    SUPPORTED_PYTHON_VERSIONS = [
+        "%s.%s" % (v[0], v[1])
+        for v in [v.split(".") for v in sorted(f.read().splitlines())]
+    ]
+
 
 venv = Venv(
     venvs=[
@@ -15,9 +20,11 @@
                         "sphinx": "==5.1.1",
                         "alabaster": "==0.7.12",
                     },
-                    pys=SUPPORTED_PYTHON_VERSIONS[2:],
+                    pys=[p for p in SUPPORTED_PYTHON_VERSIONS if p >= "3.6"],
+                ),
+                Venv(
+                    pys=[p for p in SUPPORTED_PYTHON_VERSIONS if p <= "3.5"],
                 ),
-                Venv(pys=SUPPORTED_PYTHON_VERSIONS[:2]),
             ],
             pkgs={"pytest": latest},
             command="pytest {cmdargs}",

setup.py

@@ -6,6 +6,11 @@
     long_description = f.read()
 
 
+with open("tests/.python-version", "r") as f:
+    python_versions = sorted(f.read().splitlines())
+
+min_python_version = python_versions[0].split(".")
+
 setup(
     name="envier",
     description="Python application configuration via the environment",
@@ -14,19 +19,16 @@
     author_email="[email protected]",
     classifiers=[
         "Programming Language :: Python",
-        "Programming Language :: Python :: 2.7",
-        "Programming Language :: Python :: 3.5",
-        "Programming Language :: Python :: 3.6",
-        "Programming Language :: Python :: 3.7",
-        "Programming Language :: Python :: 3.8",
-        "Programming Language :: Python :: 3.9",
-        "Programming Language :: Python :: 3.10",
+    ]
+    + [
+        "Programming Language :: Python :: %s.%s" % (v[0], v[1])
+        for v in [v.split(".") for v in python_versions]
     ],
     long_description=long_description,
     long_description_content_type="text/markdown",
     license="MIT",
     packages=find_packages(exclude=["tests*"]),
-    python_requires=">=2.7",
+    python_requires=">=%s.%s" % (min_python_version[0], min_python_version[1]),
     install_requires=["typing; python_version<'3.5'"],
     extras_require={"mypy": ["mypy"]},
     setup_requires=["setuptools_scm"],