Use cog to de-duplicate Python versions (#59)

* Use cog to de-duplicate Python versions

* oops

* another oops

.github/workflows/ci.yml

@@ -26,6 +26,17 @@ permissions:
   contents: read
 
 jobs:
+  cog-check:
+    name: Ensure cogified files are up-to-date
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-python@v4
+
+      - run: python -Im pip install --upgrade wheel nox
+
+      - run: python -Im nox -e cog -- --check
+
   build-sdist:
     name: 📦 Build the source distribution
     runs-on: ubuntu-latest
@@ -55,14 +66,18 @@ jobs:
     strategy:
       matrix:
         python-version:
+          # [[[cog
+          # for line in open("pyproject.toml"):
+          #     if "Programming Language :: Python :: " in line:
+          #         cog.outl(f'- "{line.rsplit(" ")[-1][:-3]}"')
+          # ]]]
           - "3.7"
           - "3.8"
           - "3.9"
           - "3.10"
           - "3.11"
-          - "~3.12.0-0"
-    continue-on-error: >-
-      ${{ contains(matrix.python-version, '~') && true || false }}
+          - "3.12"
+          # [[[end]]]
 
     steps:
       - name: Get source code from pre-built sdist
@@ -73,19 +88,11 @@ jobs:
       - uses: actions/setup-python@v4
         with:
           python-version: ${{ matrix.python-version }}
-      - run: python -Im pip install --upgrade wheel nox
+          allow-prereleases: true
 
-      - name: Determine Python version for Nox
-        run: |
-          V=${{ matrix.python-version }}
-          if [[ "$V" = ~* ]]; then
-            # Extract version from a '~3.XX.0-0' specifier.
-            V=${V:1:4}
-          fi
-
-          echo NOX_PYTHON=$V >>$GITHUB_ENV
+      - run: python -Im pip install --upgrade wheel nox
 
-      - run: python -Im nox --python ${{ env.NOX_PYTHON }} --tags tests
+      - run: python -Im nox --python ${{ matrix.python-version }} --tags tests
 
       - name: Upload coverage data
         uses: actions/upload-artifact@v3
@@ -139,11 +146,18 @@ jobs:
       fail-fast: false
       matrix:
         python-version:
+          # [[[cog
+          # for line in open("pyproject.toml"):
+          #     if "Programming Language :: Python :: " in line:
+          #         cog.outl(f'- "{line.rsplit(" ")[-1][:-3]}"')
+          # ]]]
           - "3.7"
           - "3.8"
           - "3.9"
           - "3.10"
           - "3.11"
+          - "3.12"
+          # [[[end]]]
 
     steps:
       - name: Get source code from pre-built sdist
@@ -154,6 +168,7 @@ jobs:
       - uses: actions/setup-python@v4
         with:
           python-version: ${{ matrix.python-version }}
+          allow-prereleases: true
       - run: python -Im pip install --upgrade wheel nox
 
       - run: python -Im nox -e mypy
@@ -170,8 +185,14 @@ jobs:
           workflow-artifact-name: ${{ env.sdist-artifact }}
       - uses: actions/setup-python@v4
         with:
-          # Keep in sync with .readthedocs.yaml
+          # [[[cog
+          # import yaml
+          # with open(".readthedocs.yaml") as f:
+          #     rtd = yaml.safe_load(f)
+          # cog.outl(f'python-version: "{rtd["build"]["tools"]["python"]}"')
+          # ]]]
           python-version: "3.11"
+          # [[[end]]]
       - run: python -Im pip install --upgrade wheel nox
 
       - run: python -Im nox -e docs

.readthedocs.yaml

@@ -2,9 +2,8 @@
 version: 2
 
 build:
-  os: ubuntu-20.04
+  os: ubuntu-22.04
   tools:
-    # Keep in sync with ci.yml/docs
     python: "3.11"
 
 python:

noxfile.py

@@ -1,9 +1,6 @@
 from __future__ import annotations
 
 import os
-import re
-
-from pathlib import Path
 
 import nox
 
@@ -12,27 +9,53 @@
 nox.options.error_on_external_run = True
 
 
-# Avoid dependencies on YAML / TOML libs using a questionable hacks.
-match_docs_python = re.compile(r"\s+python\: \"(\d\.\d\d)\"").fullmatch
-for line in Path(".readthedocs.yaml").read_text().splitlines():
-    m = match_docs_python(line)
-    if m:
-        DOCS_PYTHON = m.group(1)
-        break
+RUN_UNDER_COVERAGE = ["3.7", "3.11"]
+ALL_SUPPORTED = [
+    # [[[cog
+    # for line in open("pyproject.toml"):
+    #     if "Programming Language :: Python :: " in line:
+    #         cog.outl(f'"{line.rsplit(" ")[-1][:-3]}",')
+    # ]]]
+    "3.7",
+    "3.8",
+    "3.9",
+    "3.10",
+    "3.11",
+    "3.12",
+    # [[[end]]]
+]
+OLDEST_PYTHON = ALL_SUPPORTED[0]
+NOT_COVERAGE = [v for v in ALL_SUPPORTED if v not in RUN_UNDER_COVERAGE]
+
+# [[[cog
+# import yaml
+# with open(".readthedocs.yaml") as f:
+#     rtd = yaml.safe_load(f)
+# cog.outl(f'DOCS_PYTHON = "{rtd["build"]["tools"]["python"]}"')
+# ]]]
+DOCS_PYTHON = "3.11"
+# [[[end]]]
+
+# [[[cog
+# import tomllib
+# with open("pyproject.toml", "rb") as f:
+#     deps = tomllib.load(f)["project"]["dependencies"]
+# for dep in deps:
+#     if dep.startswith("attrs"):
+#         cog.outl(f'OLDEST_ATTRS = "{dep[7:]}"')
+#         break
+# ]]]
+OLDEST_ATTRS = "17.4.0"
+# [[[end]]]
+
 
-match_oldest_python = re.compile(
-    r"requires-python = \">=(\d\.\d+)\""
-).fullmatch
-match_oldest_attrs = re.compile(r".*\"attrs>=(\d+\.\d+\.\d+)\",.*").match
-for line in Path("pyproject.toml").read_text().splitlines():
-    m = match_oldest_python(line)
-    if m:
-        OLDEST_PYTHON = m.group(1)
+@nox.session
+def cog(session: nox.Session) -> None:
+    session.install("cogapp", "PyYAML")
 
-    m = match_oldest_attrs(line)
-    if m:
-        OLDEST_ATTRS = m.group(1)
-        break  # dependencies always come after requires-python
+    session.run(
+        "cog", *session.posargs, "-r", "noxfile.py", ".github/workflows/ci.yml"
+    )
 
 
 @nox.session
@@ -49,14 +72,14 @@ def _cov(session: nox.Session) -> None:
         session.notify("coverage_report")
 
 
-@nox.session(python=["3.7", "3.11"], tags=["tests"])
+@nox.session(python=RUN_UNDER_COVERAGE, tags=["tests"])
 def tests_cov(session: nox.Session) -> None:
     session.install(".[tests]")
 
     _cov(session)
 
 
-@nox.session(python=["3.8", "3.9", "3.10", "3.12"], tags=["tests"])
+@nox.session(python=NOT_COVERAGE, tags=["tests"])
 def tests(session: nox.Session) -> None:
     session.install(".[tests]")