Pillow/_custom_build/backend.py

from __future__ import annotations

import sys

from setuptools.build_meta import *  # noqa: F403
from setuptools.build_meta import build_wheel

backend_class = build_wheel.__self__.__class__


class _CustomBuildMetaBackend(backend_class):
    def run_setup(self, setup_script="setup.py"):
        if self.config_settings:
            for key, values in self.config_settings.items():
                if not isinstance(values, list):
                    values = [values]
                for value in values:
                    sys.argv.append(f"--pillow-configuration={key}={value}")

        return super().run_setup(setup_script)

    def build_wheel(
        self, wheel_directory, config_settings=None, metadata_directory=None
    ):
        self.config_settings = config_settings
        return super().build_wheel(wheel_directory, config_settings, metadata_directory)

    def build_editable(
        self, wheel_directory, config_settings=None, metadata_directory=None
    ):
        self.config_settings = config_settings
        return super().build_editable(
            wheel_directory, config_settings, metadata_directory
        )


_backend = _CustomBuildMetaBackend()
build_wheel = _backend.build_wheel
build_editable = _backend.build_editable