re-use ninja for CI builds

Author: mayeut

_build_backend/backend.py

@@ -1,19 +1,27 @@
+import os
+
 from scikit_build_core import build as _orig
 
-prepare_metadata_for_build_wheel = _orig.prepare_metadata_for_build_wheel
+if hasattr(_orig, "prepare_metadata_for_build_editable"):
+    prepare_metadata_for_build_editable = _orig.prepare_metadata_for_build_editable
+if hasattr(_orig, "prepare_metadata_for_build_wheel"):
+    prepare_metadata_for_build_wheel = _orig.prepare_metadata_for_build_wheel
+build_editable = _orig.build_editable
 build_wheel = _orig.build_wheel
 build_sdist = _orig.build_sdist
+get_requires_for_build_editable = _orig.get_requires_for_build_editable
 get_requires_for_build_sdist = _orig.get_requires_for_build_sdist
 
 def get_requires_for_build_wheel(config_settings=None):
     packages_orig = _orig.get_requires_for_build_wheel(config_settings)
+    allow_ninja = os.environ.get("CMAKE_PYTHON_DIST_ALLOW_NINJA_DEP", "0") != "0"
     packages = []
     for package in packages_orig:
         package_name = package.lower().split(">")[0].strip()
         if package_name == "cmake":
             msg = f"CMake PyPI distibution requires {package} to be available on the build system"
             raise ValueError(msg)
-        if package_name == "ninja":
+        if package_name == "ninja" and not allow_ninja:
             continue
         packages.append(package)
     return packages

pyproject.toml

@@ -54,8 +54,7 @@ ctest = "cmake:ctest"
 [tool.scikit-build]
 minimum-version = "build-system.requires"
 build-dir = "build/{wheel_tag}"
-cmake.version = ">=3.15"
-ninja.version = ""  # requiring ninja could cause it to request CMake if it needs to be built from sources, fallback to make
+cmake.version = ">=3.13"  # Since 3.24.0, CMake requires CMake 3.13+ to build itself
 ninja.make-fallback = true
 wheel.py-api = "py3"
 wheel.expand-macos-universal-tags = true
@@ -67,28 +66,24 @@ template = '''
 version = "${version}"
 '''
 
-[[tool.scikit-build.overrides]]
-if.env.CIBUILDWHEEL = true
-# ninja.version = ">=1.11"
-# ninja.make-fallback = false
-ninja.version = ""
-ninja.make-fallback = true
-
 [tool.cibuildwheel]
 build = "cp39-*"
 test-extras = "test"
 test-command = "pytest {project}/tests"
 build-verbosity = 1
 build-frontend = "build[uv]"
+environment = { CMAKE_PYTHON_DIST_ALLOW_NINJA_DEP = "1" }
 musllinux-x86_64-image = "musllinux_1_1"
 musllinux-i686-image = "musllinux_1_1"
 musllinux-aarch64-image = "musllinux_1_1"
 musllinux-ppc64le-image = "musllinux_1_1"
 musllinux-s390x-image = "musllinux_1_1"
 musllinux-armv7l-image = "musllinux_1_2"
 
-[tool.cibuildwheel.macos.environment]
-MACOSX_DEPLOYMENT_TARGET = "10.10"
+[[tool.cibuildwheel.overrides]]
+select = "*-macos*"
+inherit.environment = "append"
+environment = { MACOSX_DEPLOYMENT_TARGET = "10.10" }
 
 [tool.cibuildwheel.linux]
 before-all = "./scripts/manylinux-build-and-install-openssl.sh"