ci(conda): drop the unreachable Windows conda steps (#1967)

.github/workflows/create-release.yml

@@ -980,7 +980,8 @@ jobs:
           - macos-latest
           - macos-26-intel
           - ubuntu-latest
-          # - windows-latest  # skip for now
+          # No Windows leg since 2023, and no Windows steps (#1967): adding the leg
+          # back means writing its steps, as test_conda_no_windows_steps_1967 pins.
         # #1633, #1660: the supported tier only. No KTLO 3.10 leg: the list
         # util/conda_vendor.py derives omits typing-extensions, which
         # pcapkit/utilities/compat.py imports below 3.11, and pins each
@@ -1032,9 +1033,6 @@ jobs:
             ubuntu-latest)
               target_platform="linux-64"
               ;;
-            windows-latest)
-              target_platform="win-64"
-              ;;
             *)
               target_platform=""
               ;;
@@ -1083,31 +1081,18 @@ jobs:
       # installed here: on ``macos-26-intel`` they resolve a cryptography with
       # no Intel wheel, which pip has to compile or fail on.
       - name: Install and Setup
-        if: ${{ matrix.os != 'windows-latest' }}
         run: |
           set -x
 
           python -m pip install -U pip setuptools wheel
 
-      - name: Install and Setup (Windows)
-        if: ${{ matrix.os == 'windows-latest' }}
-        run: |
-          python -m pip install -U pip setuptools wheel
-
       - name: Setup Conda Distribution
-        if: ${{ matrix.os != 'windows-latest' }}
         run: |
           set -x
 
           mkdir -p conda/wheels
           python -m pip download -r conda/requirements.txt -d conda/wheels
 
-      - name: Setup Conda Distribution (Windows)
-        if: ${{ matrix.os == 'windows-latest' }}
-        run: |
-          mkdir -p conda/wheels
-          python -m pip download -r conda/requirements.txt -d conda/wheels
-
       # With `activate-environment: base`, `python-version` installs that Python
       # into base, next to conda itself. conda-forge's conda has no py315 build
       # yet, so on 3.15 that fails with "RemoveError: Conda cannot remove
@@ -1173,9 +1158,6 @@ jobs:
             ubuntu-latest)
               target_platform="linux-64"
               ;;
-            windows-latest)
-              target_platform="win-64"
-              ;;
             *)
               target_platform=""
               ;;

.github/workflows/cron-conda.yml

@@ -415,7 +415,8 @@ jobs:
           - macos-latest
           - macos-26-intel
           - ubuntu-latest
-          # - windows-latest  # skip for now
+          # No Windows leg since 2023, and no Windows steps (#1967): adding the leg
+          # back means writing its steps, as test_conda_no_windows_steps_1967 pins.
         # #1633: the supported tier, from .github/python-versions.toml through
         # `conda-update` (#1660); create-release.yml's ``conda`` job says why
         # there is no KTLO 3.10 leg.
@@ -433,34 +434,21 @@ jobs:
       # #1854: pcapkit is not installed here; see create-release.yml's step of
       # the same name.
       - name: Install and Setup
-        if: ${{ matrix.os != 'windows-latest' }}
         run: |
           set -x
 
           python -m pip install -U pip setuptools wheel
 
-      - name: Install and Setup (Windows)
-        if: ${{ matrix.os == 'windows-latest' }}
-        run: |
-          python -m pip install -U pip setuptools wheel
-
       # #1827: pip evaluates conda/requirements.txt's platform markers here,
       # on this leg's own runner, so Intel macOS fetches its own cryptography
       # pin; the recipe's build.sh installs whatever this downloaded.
       - name: Setup Conda Distribution
-        if: ${{ matrix.os != 'windows-latest' }}
         run: |
           set -x
 
           mkdir -p conda/wheels
           python -m pip download -r conda/requirements.txt -d conda/wheels
 
-      - name: Setup Conda Distribution (Windows)
-        if: ${{ matrix.os == 'windows-latest' }}
-        run: |
-          mkdir -p conda/wheels
-          python -m pip download -r conda/requirements.txt -d conda/wheels
-
       # See create-release.yml's step of the same name for the 3.15 exception.
       - name: Conda environment creation and activation
         uses: conda-incubator/setup-miniconda@be893c923ea9cf1cf7cd510fbdde27c7e18cbdcb # v4.1.0
@@ -514,9 +502,6 @@ jobs:
             ubuntu-latest)
               target_platform="linux-64"
               ;;
-            windows-latest)
-              target_platform="win-64"
-              ;;
             *)
               target_platform=""
               ;;

tests/project/test_conda_legs_install_no_pcapkit_1854.py

@@ -88,7 +88,7 @@ def test_each_install_step_upgrades_the_build_tools_alone(self) -> None:
             steps = [step for found, job, step in self.steps() if (found, job) == (name, job_id)
                      and str(step.get('name', '')).startswith('Install and Setup')]
             with self.subTest(workflow=name, job=job_id):
-                self.assertEqual(len(steps), 2, 'the Linux/macOS step and the Windows one')
+                self.assertEqual(len(steps), 1, 'one step for every leg, with no Windows twin (#1967)')
             for step in steps:
                 with self.subTest(workflow=name, job=job_id, step=step['name']):
                     self.assertEqual(installs(step), [BUILD_TOOLS])

tests/project/test_conda_no_windows_steps_1967.py

@@ -0,0 +1,113 @@
+# -*- coding: utf-8 -*-
+"""#1967: the conda jobs keep no step or ``case`` arm for a runner they have no leg on.
+
+``conda`` in :file:`.github/workflows/create-release.yml` and ``conda-dist`` in
+:file:`.github/workflows/cron-conda.yml` have had no ``windows-latest`` leg since
+2023, yet carried ``Install and Setup (Windows)``, ``Setup Conda Distribution
+(Windows)``, the ``matrix.os != 'windows-latest'`` guards on their twins, and a
+``windows-latest`` arm in each ``case "${{ matrix.os }}"``: code no run reached.
+
+* :class:`TestNoDeadRunnerCode` pins that no step's ``if:`` names a runner label
+  the job's matrix lacks, no ``case`` arm maps one, and, with no Windows leg, no
+  step is Windows-only. So adding a Windows leg back means adding its steps back
+  deliberately, rather than reviving ones nobody has run.
+* :class:`TestTheCheckSeesDeadCode` feeds :func:`dead` the jobs as they stood
+  before, rebuilt from the current ones, so the pin cannot pass by reading nothing.
+
+"""
+
+from __future__ import annotations
+
+import copy
+import re
+import unittest
+from typing import TYPE_CHECKING
+
+from tests import _workflows
+
+if TYPE_CHECKING:
+    from typing import Any
+
+#: Test tier (#1958): reads the workflow files, a question about the tree.
+__tier__ = 'LATEST'
+
+#: The conda jobs, as (workflow, job).
+JOBS = (('create-release.yml', 'conda'), ('cron-conda.yml', 'conda-dist'))
+#: A ``matrix.os`` comparison in an ``if:``, capturing the label compared against.
+GUARD = re.compile(r"matrix\.os\s*[!=]=\s*'([^']+)'")
+#: A ``case "${{ matrix.os }}" in`` block of a step's ``run:``.
+CASE = re.compile(r'case "\$\{\{ matrix\.os \}\}" in\n(.*?)\n\s*esac', re.DOTALL)
+#: An arm of that block, capturing its pattern.
+ARM = re.compile(r'^\s*([^\s()]+)\)\s*$', re.MULTILINE)
+#: A Windows runner label, or the step name of a Windows-only step.
+WINDOWS = re.compile(r'windows', re.IGNORECASE)
+#: An ``if:`` that runs its step on Windows alone.
+WINDOWS_ONLY = re.compile(r"(?:matrix|runner)\.os\s*==\s*'[^']*windows", re.IGNORECASE)
+
+
+def dead(spec: 'dict[str, Any]') -> 'list[str]':
+    """What of ``spec``, a job, names a runner its matrix has no leg on."""
+    labels = list(spec['strategy']['matrix']['os'])
+    windows_leg = any(WINDOWS.search(label) for label in labels)
+    found = []
+    for step in spec['steps']:
+        name = str(step.get('name') or step.get('uses') or step.get('id'))
+        condition = str(step.get('if', ''))
+        for label in GUARD.findall(condition):
+            if label not in labels:
+                found.append(f'{name}: `if:` compares matrix.os with {label}, which is no leg')
+        if not windows_leg and (WINDOWS_ONLY.search(condition) or WINDOWS.search(str(step.get('name', '')))):
+            found.append(f'{name}: Windows-only, and no leg is Windows')
+        for block in CASE.findall(str(step.get('run', ''))):
+            for pattern in ARM.findall(block):
+                if pattern != '*' and pattern not in labels:
+                    found.append(f'{name}: `case` arm {pattern}, which is no leg')
+    return found
+
+
+class TestNoDeadRunnerCode(unittest.TestCase):
+    """Each conda job's steps and ``case`` arms cover its legs and nothing else."""
+
+    def test_no_step_or_arm_names_a_missing_leg(self) -> None:
+        for name, job_id in JOBS:
+            with self.subTest(workflow=name, job=job_id):
+                self.assertEqual(dead(_workflows.job(name, job_id)), [])
+
+
+class TestTheCheckSeesDeadCode(unittest.TestCase):
+    """:func:`dead` reports each kind of dead code the jobs held before #1967."""
+
+    def test_it_reports_a_windows_step_guard_and_arm(self) -> None:
+        for name, job_id in JOBS:
+            spec = copy.deepcopy(_workflows.job(name, job_id))
+            install = next(step for step in spec['steps'] if step.get('name') == 'Install and Setup')
+            install['if'] = "${{ matrix.os != 'windows-latest' }}"
+            spec['steps'].append({'name': 'Install and Setup (Windows)',
+                                  'if': "${{ matrix.os == 'windows-latest' }}",
+                                  'run': 'python -m pip install -U pip setuptools wheel\n'})
+            spec['steps'].append({'name': 'Map the leg', 'run': (
+                'case "${{ matrix.os }}" in\n'
+                '  windows-latest)\n'
+                '    target_platform="win-64"\n'
+                '    ;;\n'
+                '  *)\n'
+                '    target_platform=""\n'
+                '    ;;\n'
+                'esac\n')})
+            with self.subTest(workflow=name, job=job_id):
+                self.assertEqual(dead(spec), [
+                    'Install and Setup: `if:` compares matrix.os with windows-latest, which is no leg',
+                    'Install and Setup (Windows): `if:` compares matrix.os with windows-latest, which is no leg',
+                    'Install and Setup (Windows): Windows-only, and no leg is Windows',
+                    'Map the leg: `case` arm windows-latest, which is no leg',
+                ])
+
+    def test_a_windows_leg_allows_its_own_steps(self) -> None:
+        spec = {'strategy': {'matrix': {'os': ['ubuntu-latest', 'windows-latest']}},
+                'steps': [{'name': 'Setup (Windows)', 'if': "${{ matrix.os == 'windows-latest' }}",
+                           'run': 'case "${{ matrix.os }}" in\n  windows-latest)\n    x=1\n    ;;\nesac\n'}]}
+        self.assertEqual(dead(spec), [])
+
+
+if __name__ == '__main__':
+    unittest.main()

util/conda_vendor.py

@@ -103,7 +103,7 @@
 #: ``sys.platform``, ``platform.system()`` and ``platform.machine()`` read on its
 #: runner: ``ubuntu-latest``, the Intel ``macos-26-intel`` and the arm64
 #: ``macos-latest``. Each leg publishes only its own runner's platform (#1822).
-#: Their Windows legs are commented out, and with them the recipe's ``bld.bat``.
+#: They have no Windows leg (#1967), so the recipe's ``bld.bat`` goes unused.
 PLATFORMS = {
     'linux-64': ('linux', 'Linux', 'x86_64'),
     'osx-64': ('darwin', 'Darwin', 'x86_64'),