Windows: Set CMAKE_PREFIX_PATH in before-build script using command substitution

Author: jeongseok-meta

pyproject-pypi.toml.j2

@@ -277,13 +277,15 @@ environment = { CMAKE_PREFIX_PATH = "$PWD/.pixi/envs/default", MOMENTUM_BUILD_WI
 build-frontend = "pip; args: --no-build-isolation"
 # Install build dependencies before building (since we disabled build isolation)
 # Note: cibuildwheel runs before-build scripts in bash even on Windows, so use bash syntax
+# We set CMAKE_PREFIX_PATH here because $PWD doesn't expand in the environment config on Windows
 before-build = """
+export CMAKE_PREFIX_PATH="$(pwd)/.pixi/envs/default"
 echo "Debug: CMAKE_PREFIX_PATH=$CMAKE_PREFIX_PATH"
 ls -la "$CMAKE_PREFIX_PATH/Library/lib/cmake/Ceres" 2>/dev/null || echo "Ceres cmake dir not found"
 pip install scikit-build-core pybind11 setuptools-scm
 pip install "torch>=2.8.0,<2.9" --index-url https://download.pytorch.org/whl/cpu
 """
-# Set CMAKE_PREFIX_PATH using $PWD which is available at build time
-# On Windows with conda-forge, cmake files are in Library/lib/cmake
-environment = { CMAKE_PREFIX_PATH = "$PWD/.pixi/envs/default", MOMENTUM_BUILD_WITH_FBXSDK = "OFF" }
+# On Windows, do NOT set CMAKE_PREFIX_PATH here - $PWD doesn't expand properly
+# Instead, we export it in before-build script above
+environment = { MOMENTUM_BUILD_WITH_FBXSDK = "OFF" }
 {% endif %}