Enabling M1 runners for Python package building inside github actions

.github/workflows/build.yml

@@ -20,8 +20,12 @@ jobs:
       max-parallel: 12
       matrix:
         include:
-          - os: "macos-latest"
+          - os: "macos-13"  # intel runner
             cibuild: "*macosx*"
+            macos-arch: "x86_64"
+          - os: "macos-14"  # M1 runner
+            cibuild: "*macosx*"
+            macos-arch: "arm64"
           - os: "ubuntu-latest"
             cibuild: "*manylinux*"
           - os: "ubuntu-latest"
@@ -58,6 +62,7 @@ jobs:
         #   CIBW_SOME_OPTION: value
         env:
           CIBW_BUILD: ${{ matrix.cibuild }}
+          CIBW_ARCHS_MACOS: ${{ matrix.macos-arch }}
 
       - name: Download Cache from Docker (linux only)
         if: ${{ runner.os == 'Linux' }}

ci-scripts/macos/libpng-patch.sh

@@ -1,29 +0,0 @@
-# Solves issue #1346
-# Deprecate patch when Github Actions provides Apple Silicon runners.
-# WARNING: Only run this in a CI runner
-
-# Issue: klayout depends on libpng, which is loaded by homebrew.
-# But M1 wheels are cross-compiled in an intel host, so by default
-# libpng.dylib has an x86 architecture. This prevents linking the library
-# in the tl library.
-
-# Patch solution: manually download libpng arm64 pre-built library from homebrew
-
-# Reading
-# https://stackoverflow.com/questions/55110564/how-can-i-install-a-homebrew-bottle-designed-for-a-different-previous-version
-# https://github.com/Homebrew/homebrew-core/blob/6abea16e917b12d6af4912736f66eb8d42bf089b/Formula/libpng.rb
-
-export HOMEBREW_NO_INSTALL_CLEANUP=1
-export HOMEBREW_NO_INSTALLED_DEPENDENTS_CHECK=1
-
-# Check if we're about to build an arm64 wheel. WARNING universal wheels not supported
-if [ "$_PYTHON_HOST_PLATFORM" == "macosx-11.0-arm64" ]
-then
-    # Exit early if done
-    test -f /tmp/libpng-apple-silicon-installed && exit 0
-    curl -L -H "Authorization: Bearer QQ==" -o /tmp/libpng-1.6.39.arm64_big_sur.bottle.1.tar.gz https://ghcr.io/v2/homebrew/core/libpng/blobs/sha256:cf59cedc91afc6f2f3377567ba82b99b97744c60925a5d1df6ecf923fdb2f234
-    brew reinstall -f /tmp/libpng-1.6.39.arm64_big_sur.bottle.1.tar.gz || exit 1
-    touch /tmp/libpng-apple-silicon-installed
-elif [ -f "/tmp/libpng-apple-silicon-installed" ]; then
-    brew reinstall -f libpng && rm -f /tmp/libpng-apple-silicon-installed
-fi

pyproject.toml

@@ -11,9 +11,6 @@ test-command = [
 # Disable building PyPy wheels on all platforms
 skip = "pp*"
 
-# Skip trying to test arm64 builds on Intel Macs
-test-skip = "*-macosx_arm64 *-macosx_universal2:arm64"
-
 [tool.cibuildwheel.linux]
 # beware: the before-all script does not persist environment variables!
 # No point in defining $PATH or $CCACHE_DIR
@@ -27,17 +24,5 @@ before-build = "ccache -s"
 environment-pass = ["HOST_CCACHE_DIR"]
 
 [tool.cibuildwheel.macos]
-before-all = [
-  "brew install libpng",
-  "brew deps --tree --installed",
-]
-
-# TEMP while Github Actions does not provide an Apple Silicon runner
-# TODO Simply remove it when it's available
-archs = ["x86_64", "arm64"]
-before-build = [
-  "ccache -s",
-  "bash {project}/ci-scripts/macos/libpng-patch.sh",
-]
 # Repair macOS wheels (include libpng with the wheel, for example)
-repair-wheel-command = "delocate-wheel --require-archs {delocate_archs} -w {dest_dir} -v --ignore-missing-dependencies {wheel}"
+repair-wheel-command = "delocate-wheel --require-archs {delocate_archs} -w {dest_dir} -v --ignore-missing-dependencies {wheel}"