setup.py

"""
Custom CMake build logic for qpandalite_cpp extension.

Metadata and dependencies are defined in pyproject.toml.
This file is retained solely for CMakeExtension / CMakeBuild,
which cannot be expressed declaratively in pyproject.toml.
"""
import re
from setuptools import setup, Extension, find_packages
from setuptools.command.build_ext import build_ext
import os
import subprocess
import sys

BUILD_WITH_CPP = True

# see if user passes any args to the setup
filtered_args = []
for i, arg in enumerate(sys.argv):
    if arg == '--no-cpp':
        BUILD_WITH_CPP = False
        print('Build without C++ support.')
    else:
        filtered_args.append(arg)

sys.argv = filtered_args

# Convert distutils Windows platform specifiers to CMake -A arguments
PLAT_TO_CMAKE = {
    "win32": "Win32",
    "win-amd64": "x64",
    "win-arm32": "ARM",
    "win-arm64": "ARM64",
}


class CMakeExtension(Extension):
    def __init__(self, name, sourcedir=""):
        Extension.__init__(self, name, sources=[])
        self.sourcedir = os.path.abspath(sourcedir)


class CMakeBuild(build_ext):
    def build_extension(self, ext):
        extdir = os.path.abspath(os.path.dirname(self.get_ext_fullpath(ext.name)))

        # required for auto-detection & inclusion of auxiliary "native" libs
        if not extdir.endswith(os.path.sep):
            extdir += os.path.sep

        debug = int(os.environ.get("DEBUG", 0)) if self.debug is None else self.debug
        cfg = "Debug" if debug else "Release"

        # CMake lets you override the generator - we need to check this.
        # Can be set with Conda-Build, for example.
        cmake_generator = os.environ.get("CMAKE_GENERATOR", "")

        cmake_args = [
            f"-DCMAKE_LIBRARY_OUTPUT_DIRECTORY={extdir}",
            f"-DCMAKE_BUILD_TYPE={cfg}",  # not used on MSVC, but no harm
        ]
        build_args = []

        # Adding CMake arguments set as environment variable
        # (needed e.g. to build for ARM OSx on conda-forge)
        if "CMAKE_ARGS" in os.environ:
            cmake_args += [item for item in os.environ["CMAKE_ARGS"].split(" ") if item]

        # In this example, we pass in the version to C++. You might not need to.
        cmake_args += [f"-DEXAMPLE_VERSION_INFO={self.distribution.get_version()}"]

        if self.compiler.compiler_type != "msvc":
            # Using Ninja-build since it a) is available as a wheel and b)
            # multithreads automatically. Not using MSVC.
            if not cmake_generator:
                try:
                    import ninja  # noqa: F401

                    cmake_args += ["-GNinja"]
                except ImportError:
                    pass
            # Let CMake auto-detect the C++ compiler instead of hardcoding one.
        else:
            # Single config generators are handled "normally"
            single_config = any(x in cmake_generator for x in {"NMake", "Ninja"})

            # CMake allows an arch-in-generator style for backward compatibility
            contains_arch = any(x in cmake_generator for x in {"ARM", "Win64"})

            # Specify the arch if using MSVC generator, but only if it doesn't
            # contain a backward-compatibility arch spec already in the
            # generator name.
            if not single_config and not contains_arch:
                cmake_args += ["-A", PLAT_TO_CMAKE[self.plat_name]]

            # Multi-config generators have a different way to specify configs
            if not single_config:
                cmake_args += [
                    f"-DCMAKE_LIBRARY_OUTPUT_DIRECTORY_{cfg.upper()}={extdir}"
                ]
                build_args += ["--config", cfg]

        if sys.platform.startswith("darwin"):
            # Cross-compile support for macOS - respect ARCHFLAGS if set
            archs = re.findall(r"-arch (\S+)", os.environ.get("ARCHFLAGS", ""))
            if archs:
                cmake_args += ["-DCMAKE_OSX_ARCHITECTURES={}".format(";".join(archs))]

        # Set CMAKE_BUILD_PARALLEL_LEVEL to control the parallel build level
        # across all generators.
        if "CMAKE_BUILD_PARALLEL_LEVEL" not in os.environ:
            # self.parallel is a Python 3 only way to set parallel jobs by hand
            # using -j in the build_ext call, not supported by pip or PyPA-build.
            if hasattr(self, "parallel") and self.parallel:
                # CMake 3.12+ only.
                build_args += [f"-j{self.parallel}"]

        if not os.path.exists(self.build_temp):
            os.makedirs(self.build_temp)

        print(cmake_args)
        subprocess.check_call(
            ["cmake", ext.sourcedir] + cmake_args, cwd=self.build_temp
        )
        print(build_args)

        subprocess.check_call(
            ["cmake", "--build", "."] + build_args, cwd=self.build_temp
        )


if BUILD_WITH_CPP:
    ext_modules = [CMakeExtension("qpandalite_cpp")]
    cmdclass = {"build_ext": CMakeBuild}
else:
    ext_modules = []
    cmdclass = {}

setup(
    ext_modules=ext_modules,
    cmdclass=cmdclass,
)