fix: install setuptools for the packaging guard

.github/workflows/validate.yml

@@ -223,8 +223,9 @@ jobs:
       # heading guard's premise, and skipped on every run without it. pyte
       # reads the installer's full screen back in its end-to-end tests,
       # hypothesis fuzzes its key decoder, and vermin holds install.py to 3.8.
+      # setuptools reads pyproject.toml for the packaging guard.
       - name: Install dependencies
-        run: pip install pyyaml "jsonschema[format-nongpl]==4.26.0" "markdown==3.10.2" "pyte==0.8.2" "hypothesis==6.170.8" "vermin==1.9.2"
+        run: pip install pyyaml "jsonschema[format-nongpl]==4.26.0" "markdown==3.10.2" "pyte==0.8.2" "hypothesis==6.170.8" "vermin==1.9.2" "setuptools==80.9.0"
 
       # The full screen also runs under the 3.8 floor: the end-to-end tests
       # start install.py with the interpreter that runs them.

CONTRIBUTING.md

@@ -68,7 +68,7 @@ validation above is its check. For code, profiles or platform files, these are
 the checks CI runs on a pull request (Python 3.12 or newer):
 
 ```bash
-pip install pyyaml "jsonschema[format-nongpl]" markdown pyte hypothesis vermin
+pip install pyyaml "jsonschema[format-nongpl]" markdown pyte hypothesis vermin setuptools
 python scripts/validate_pr.py --changed          # the BIOS files the branch adds
 python scripts/validate_schemas.py --source-only # profiles and platform files
 python scripts/profile_sync.py --added --base upstream/main --strict  # each profile the branch adds

pyproject.toml

@@ -33,6 +33,10 @@ dev = [
     "pyte>=0.8.2",
     "hypothesis>=6.100",
     "vermin>=1.9",
+    # The packaging guard reads this file through setuptools, which pip
+    # installs only in its isolated build environment and 3.12 no longer
+    # bundles: without it the guard skipped on every CI run.
+    "setuptools>=61",
 ]
 # The site is built by Astro Starlight from website/package.json and its
 # lockfile (npm ci --prefix website): no Python package builds it.

scripts/generate_readme.py

@@ -974,7 +974,7 @@ validation above is its check. For code, profiles or platform files, these are
 the checks CI runs on a pull request (Python 3.12 or newer):
 
 ```bash
-pip install pyyaml "jsonschema[format-nongpl]" markdown pyte hypothesis vermin
+pip install pyyaml "jsonschema[format-nongpl]" markdown pyte hypothesis vermin setuptools
 python scripts/validate_pr.py --changed          # the BIOS files the branch adds
 python scripts/validate_schemas.py --source-only # profiles and platform files
 python scripts/profile_sync.py --added --base upstream/main --strict  # each profile the branch adds

tests/test_audit_regressions.py

@@ -2766,6 +2766,10 @@ class TheProjectInstallsWithPip(unittest.TestCase):
         import importlib.util  # noqa: PLC0415
 
         if importlib.util.find_spec("setuptools") is None:
+            # The dev extra and CI install it: skipped there, the guard held
+            # nothing on any run.
+            if os.environ.get("CI"):
+                self.fail("CI must install setuptools")
             self.skipTest("setuptools is not installed")
         program = (
             "from setuptools.dist import Distribution\n"