Modernize wheel building job config (google#1783)

It is now possible to build Mac wheels on native machines in Github
Actions, so ARM64 Mac wheels are now built and tested on M1 machines.

Also, the artifact up-/download was migrated to v4, which made it
necessary to upload wheels to unique artifact names, and then later
stitch them together again in a subsequent job.

The cross-platform Mac build injection in setup.py was removed,
since it is no longer necessary.

I relanded a monkey-patching of Bazel build files, this time for
MODULE.bazel. This is because `rules_python` does not allow running
as the root user, which is the case in cibuildwheel+Linux (happens
in a Docker container). Since I did not see a quick way of switching
to rootless containers, and did not want to hardcode the config change
(it can apparently cause cache misses and build failures), I inject the
"ignore_root_user_error" flag into the MODULE.bazel file when running
in cibuildwheel on Linux.

.github/install_bazel.sh

@@ -3,11 +3,10 @@ if ! bazel version; then
   if [ "$arch" == "aarch64" ]; then
     arch="arm64"
   fi
-  echo "Installing wget and downloading $arch Bazel binary from GitHub releases."
-  yum install -y wget
-  wget "https://github.com/bazelbuild/bazel/releases/download/6.4.0/bazel-6.4.0-linux-$arch" -O /usr/local/bin/bazel
-  chmod +x /usr/local/bin/bazel
+  echo "Downloading $arch Bazel binary from GitHub releases."
+  curl -L -o $HOME/bin/bazel --create-dirs "https://github.com/bazelbuild/bazel/releases/download/7.1.1/bazel-7.1.1-linux-$arch"
+  chmod +x $HOME/bin/bazel
 else
-  # bazel is installed for the correct architecture
+  # Bazel is installed for the correct architecture
   exit 0
 fi

.github/workflows/wheels.yml

@@ -15,24 +15,24 @@ jobs:
         uses: actions/checkout@v4
         with:
           fetch-depth: 0
-      - name: Install Python 3.11
+      - name: Install Python 3.12
         uses: actions/setup-python@v5
         with:
-          python-version: 3.11
+          python-version: 3.12
       - run: python -m pip install build
       - name: Build sdist
         run: python -m build --sdist
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
-          name: dist
+          name: dist-sdist
           path: dist/*.tar.gz
 
   build_wheels:
     name: Build Google Benchmark wheels on ${{ matrix.os }}
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ubuntu-latest, macos-latest, windows-latest]
+        os: [ubuntu-latest, macos-13, macos-14, windows-latest]
 
     steps:
       - name: Check out Google Benchmark
@@ -47,32 +47,44 @@ jobs:
           platforms: all
 
       - name: Build wheels on ${{ matrix.os }} using cibuildwheel
-        uses: pypa/cibuildwheel@v2.16.2
+        uses: pypa/cibuildwheel@v2.17
         env:
-          CIBW_BUILD: 'cp38-* cp39-* cp310-* cp311-* cp312-*'
+          CIBW_BUILD: "cp38-* cp39-* cp310-* cp311-* cp312-*"
           CIBW_SKIP: "*-musllinux_*"
-          CIBW_TEST_SKIP: "*-macosx_arm64"
-          CIBW_ARCHS_LINUX: x86_64 aarch64
-          CIBW_ARCHS_MACOS: x86_64 arm64
-          CIBW_ARCHS_WINDOWS: AMD64
+          CIBW_TEST_SKIP: "cp38-macosx_*:arm64"
+          CIBW_ARCHS_LINUX: auto64 aarch64
+          CIBW_ARCHS_WINDOWS: auto64
           CIBW_BEFORE_ALL_LINUX: bash .github/install_bazel.sh
+          # Grab the rootless Bazel installation inside the container.
+          CIBW_ENVIRONMENT_LINUX: PATH=$PATH:$HOME/bin
           CIBW_TEST_COMMAND: python {project}/bindings/python/google_benchmark/example.py
 
       - name: Upload Google Benchmark ${{ matrix.os }} wheels
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
-          name: dist
+          name: dist-${{ matrix.os }}
           path: wheelhouse/*.whl
 
+  merge_wheels:
+    name: Merge all built wheels into one artifact
+    runs-on: ubuntu-latest
+    needs: build_wheels
+    steps:
+      - name: Merge wheels
+        uses: actions/upload-artifact/merge@v4
+        with:
+          name: dist
+          pattern: dist-*
+          delete-merged: true
+
   pypi_upload:
     name: Publish google-benchmark wheels to PyPI
-    needs: [build_sdist, build_wheels]
+    needs: [merge_wheels]
     runs-on: ubuntu-latest
     permissions:
       id-token: write
     steps:
-    - uses: actions/download-artifact@v3
-      with:
-        name: dist
-        path: dist
-    - uses: pypa/[email protected]
+      - uses: actions/download-artifact@v4
+        with:
+          path: dist
+      - uses: pypa/gh-action-pypi-publish@v1

MODULE.bazel

@@ -27,10 +27,6 @@ python.toolchain(
     is_default = True,
     python_version = "3.12",
 )
-use_repo(
-    python,
-    python = "python_versions",
-)
 
 pip = use_extension("@rules_python//python/extensions:pip.bzl", "pip", dev_dependency = True)
 pip.parse(

setup.py

@@ -1,14 +1,17 @@
+import contextlib
 import os
 import platform
+import re
 import shutil
 from pathlib import Path
-from typing import Any
+from typing import Any, Generator
 
 import setuptools
 from setuptools.command import build_ext
 
 IS_WINDOWS = platform.system() == "Windows"
 IS_MAC = platform.system() == "Darwin"
+IS_LINUX = platform.system() == "Linux"
 
 # hardcoded SABI-related options. Requires that each Python interpreter
 # (hermetic or not) participating is of the same major-minor version.
@@ -17,6 +20,46 @@
 options = {"bdist_wheel": {"py_limited_api": "cp312"}} if py_limited_api else {}
 
 
+def is_cibuildwheel() -> bool:
+    return os.getenv("CIBUILDWHEEL") is not None
+
+
+@contextlib.contextmanager
+def _maybe_patch_toolchains() -> Generator[None, None, None]:
+    """
+    Patch rules_python toolchains to ignore root user error
+    when run in a Docker container on Linux in cibuildwheel.
+    """
+
+    def fmt_toolchain_args(matchobj):
+        suffix = "ignore_root_user_error = True"
+        callargs = matchobj.group(1)
+        # toolchain def is broken over multiple lines
+        if callargs.endswith("\n"):
+            callargs = callargs + "    " + suffix + ",\n"
+        # toolchain def is on one line.
+        else:
+            callargs = callargs + ", " + suffix
+        return "python.toolchain(" + callargs + ")"
+
+    CIBW_LINUX = is_cibuildwheel() and IS_LINUX
+    try:
+        if CIBW_LINUX:
+            module_bazel = Path("MODULE.bazel")
+            content: str = module_bazel.read_text()
+            module_bazel.write_text(
+                re.sub(
+                    r"python.toolchain\(([\w\"\s,.=]*)\)",
+                    fmt_toolchain_args,
+                    content,
+                )
+            )
+        yield
+    finally:
+        if CIBW_LINUX:
+            module_bazel.write_text(content)
+
+
 class BazelExtension(setuptools.Extension):
     """A C/C++ extension that is defined as a Bazel BUILD target."""
 
@@ -73,21 +116,11 @@ def bazel_build(self, ext: BazelExtension) -> None:
             for library_dir in self.library_dirs:
                 bazel_argv.append("--linkopt=/LIBPATH:" + library_dir)
         elif IS_MAC:
-            if platform.machine() == "x86_64":
-                # C++17 needs macOS 10.14 at minimum
-                bazel_argv.append("--macos_minimum_os=10.14")
-
-                # cross-compilation for Mac ARM64 on GitHub Mac x86 runners.
-                # ARCHFLAGS is set by cibuildwheel before macOS wheel builds.
-                archflags = os.getenv("ARCHFLAGS", "")
-                if "arm64" in archflags:
-                    bazel_argv.append("--cpu=darwin_arm64")
-                    bazel_argv.append("--macos_cpus=arm64")
-
-            elif platform.machine() == "arm64":
-                bazel_argv.append("--macos_minimum_os=11.0")
+            # C++17 needs macOS 10.14 at minimum
+            bazel_argv.append("--macos_minimum_os=10.14")
 
-        self.spawn(bazel_argv)
+        with _maybe_patch_toolchains():
+            self.spawn(bazel_argv)
 
         if IS_WINDOWS:
             suffix = ".pyd"