ci: fix the broken Python and WASM library builds (solvespace#1565)

* build: pin the Python build CMake version to 3.31.6

CMake 4.0.0 broke compatibility with versions earlier than 3.5, and the
CI build has been failing because of it with error "Compatibility with
CMake < 3.5 has been removed from CMake".

This is caused by the CMake dependency version not being specified in
`pyproject.toml`, which caused it to pull the latest version.

* build: add components to CMake installation rules

This allows the Python build to avoid failure when only the Python library
is being built, as installation cannot find the targets that haven't been
built.

* ci: fix the WASM library build

Somehow during the rebase I silently dropped the `--target` flag to the
CMake build. Also, while changing it to `RelWithDebInfo`, I completely
missed the fact that the variable was `DCMAKE_RELEASE_TYPE` instead of
the correct `DCMAKE_BUILD_TYPE`.

Author: iscgar

.github/scripts/build-wasmlib.sh

@@ -10,12 +10,12 @@ source ../emsdk/emsdk_env.sh
 mkdir -p build-wasmlib
 cd build-wasmlib
 emcmake cmake .. \
-  -DCMAKE_RELEASE_TYPE=RelWithDebInfo \
+  -DCMAKE_BUILD_TYPE=RelWithDebInfo \
   -DENABLE_GUI="OFF" \
   -DENABLE_CLI="OFF" \
   -DENABLE_TESTS="OFF" \
   -DENABLE_COVERAGE="OFF" \
   -DENABLE_OPENMP="OFF" \
   -DFORCE_VENDORED_Eigen3="ON" \
   -DENABLE_LTO="ON"
-cmake --build . -j$(nproc) slvs-wasm
+cmake --build . -j$(nproc) --target slvs-wasm

pyproject.toml

@@ -1,5 +1,5 @@
 [build-system]
-requires = ["scikit-build-core", "Cython", "cmake", "ninja"]
+requires = ["scikit-build-core", "Cython", "cmake==3.31.6", "ninja"]
 build-backend = "scikit_build_core.build"
 
 [project]
@@ -29,6 +29,7 @@ wheel.expand-macos-universal-tags = true
 cmake.verbose = true
 cmake.build-type = "RelWithDebInfo"
 build.targets = ["slvs-py"]
+install.components = ["python"]
 sdist.include = [
   ".git/HEAD",
   ".git/refs"

src/CMakeLists.txt

@@ -405,10 +405,12 @@ endif()
 if(NOT (WIN32 OR APPLE OR EMSCRIPTEN))
     if(ENABLE_GUI)
         install(TARGETS solvespace
+            COMPONENT   solvespace
             RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
     endif()
     if(ENABLE_CLI)
         install(TARGETS solvespace-cli
+            COMPONENT   solvespace
             RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR})
     endif()
 endif()

src/slvs/CMakeLists.txt

@@ -26,12 +26,19 @@ if(ENABLE_PYTHON_LIB)
     )
     set_target_properties(slvs-py PROPERTIES LIBRARY_OUTPUT_NAME solvespace)
     if(SKBUILD)
-        install(TARGETS slvs-py DESTINATION ${SKBUILD_PROJECT_NAME})
+        install(TARGETS slvs-py
+            DESTINATION ${SKBUILD_PROJECT_NAME}
+            COMPONENT   python
+        )
     else()
-        install(TARGETS slvs-py DESTINATION "slvs")
+        install(TARGETS slvs-py
+            DESTINATION "slvs"
+            COMPONENT   python
+        )
         install(
             DIRECTORY ${CMAKE_SOURCE_DIR}/python/slvs/
             DESTINATION "slvs"
+            COMPONENT   python
         )
     endif()
 endif()
@@ -65,6 +72,7 @@ set_target_properties(slvs PROPERTIES
 
 # if(NOT WIN32)
 install(TARGETS slvs
+    COMPONENT     slvs
     LIBRARY       DESTINATION ${CMAKE_INSTALL_LIBDIR}
     ARCHIVE       DESTINATION ${CMAKE_INSTALL_LIBDIR}
     PUBLIC_HEADER DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})