allow to force ninja

Author: mayeut

_build_backend/backend.py

@@ -12,9 +12,25 @@
 get_requires_for_build_editable = _orig.get_requires_for_build_editable
 get_requires_for_build_sdist = _orig.get_requires_for_build_sdist
 
+
+def strtobool(value: str) -> bool:
+    """
+    Converts a environment variable string into a boolean value.
+    """
+    if not value:
+        return False
+    value = value.lower()
+    if value.isdigit():
+        return bool(int(value))
+    return value not in {"n", "no", "off", "false", "f"}
+
+
 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"
+    allow_ninja = any(
+        strtobool(os.environ.get(var, ""))
+        for var in ("CMAKE_PYTHON_DIST_FORCE_NINJA_DEP", "CMAKE_PYTHON_DIST_ALLOW_NINJA_DEP")
+    )
     packages = []
     for package in packages_orig:
         package_name = package.lower().split(">")[0].strip()

pyproject.toml

@@ -66,13 +66,18 @@ template = '''
 version = "${version}"
 '''
 
+[[tool.scikit-build.overrides]]
+if.env.CMAKE_PYTHON_DIST_FORCE_NINJA_DEP = true
+ninja.make-fallback = false
+
+
 [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" }
+environment = { CMAKE_PYTHON_DIST_FORCE_NINJA_DEP = "1" }
 musllinux-x86_64-image = "musllinux_1_1"
 musllinux-i686-image = "musllinux_1_1"
 musllinux-aarch64-image = "musllinux_1_1"