Feat: `ihta_package_python_wheel`

Add the ihta_package_python_wheel function; this allows packaging an executable in a Python wheel from CMake.

src/IhtaPackagePythonWheel.cmake

+include_guard ()
+
+#[=======================================================================[.rst:
+..command:: ihta_package_python_wheel
+
+	Macro to create a Python wheel package from a target.
+
+	::
+
+		ihta_package_python_wheel(
+			TARGET_NAME <target-name>
+			[PACKAGE_NAME <package-name>]
+			[VERSION <package-version>]
+			[OUTPUT_VAR <output-variable-name>]
+		)
+
+	.. variable:: TARGET_NAME
+
+		Name of the target to package.
+
+	.. variable:: PACKAGE_NAME
+
+		Name of the package. If not given, the target name will be used.
+
+	.. variable:: VERSION
+
+		Version of the package. If not given, the version will be set to `0.0.0`.
+
+	.. variable:: OUTPUT_VAR
+
+		Name of the variable to store the output directory of the wheel package.
+
+#]=======================================================================]
+function (ihta_package_python_wheel)
+	set (options)
+	set (oneValueArgs TARGET_NAME PACKAGE_NAME VERSION OUTPUT_VAR)
+	set (multiValueArgs)
+	cmake_parse_arguments (PACK_WHL "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
+
+	if (NOT PACK_WHL_PACKAGE_NAME)
+		set (PACK_WHL_PACKAGE_NAME ${PACK_WHL_TARGET_NAME})
+	endif ()
+
+	if (NOT PACK_WHL_VERSION)
+		message (WARNING "No version specified for Python wheel package. Defaulting to 0.0.0")
+		set (PACK_WHL_VERSION "0.0.0")
+	endif ()
+
+	find_package (Python3 REQUIRED COMPONENTS Interpreter)
+
+	set (PACKAGE_WHL_BASE_DIR ${CMAKE_BINARY_DIR}/ihta_pack_whl)
+	set (PACKAGE_WORKING_DIR ${PACKAGE_WHL_BASE_DIR}/${PACK_WHL_PACKAGE_NAME})
+	set (PACKAGE_INIT_DIR ${PACKAGE_WORKING_DIR}/src/${PACK_WHL_PACKAGE_NAME})
+	set (DIST_DIR ${PACKAGE_WORKING_DIR}/dist)
+
+	set (
+		BUILDER_PLUGIN_CONTENT
+		[[
+from hatchling.builders.hooks.plugin.interface import BuildHookInterface
+
+from typing import Any
+import sysconfig
+
+class CustomBuildHook(BuildHookInterface):
+	def initialize(self, version: str, build_data: dict[str, Any]) -> None:
+		build_data["pure_python"] = True
+		build_data["infer_tag"] = False
+
+		platform_tag = sysconfig.get_platform()
+		platform_tag = platform_tag.replace("-", "_").replace(".", "_")
+
+		build_data["tag"] = f"py3-none-{platform_tag}"
+	]]
+	)
+
+	set (
+		PYPROJECT_CONTENT
+		"
+[build-system]
+requires = [\"hatchling\"]
+build-backend = \"hatchling.build\"
+
+[project]
+name = \"${PACK_WHL_PACKAGE_NAME}\"
+description = \"Package containing the ${PACK_WHL_TARGET_NAME} executable\"
+requires-python = \">=3.9\"
+version = \"${PACK_WHL_VERSION}\"
+
+[tool.hatch.build.targets.wheel.hooks.custom]
+path = \"builder_plugin.py\"
+	"
+	)
+
+	file (
+		GENERATE
+		OUTPUT ${PACKAGE_WORKING_DIR}/src/${PACK_WHL_PACKAGE_NAME}/__init__.py
+		CONTENT "from pathlib import Path
+
+EXECUTABLE_PATH = Path(__file__).parent / \"$<TARGET_FILE_NAME:${PACK_WHL_TARGET_NAME}>\"
+__version__ = \"${PACK_WHL_VERSION}\""
+	)
+	file (
+		GENERATE
+		OUTPUT ${PACKAGE_WORKING_DIR}/builder_plugin.py
+		CONTENT "${BUILDER_PLUGIN_CONTENT}"
+	)
+	file (
+		GENERATE
+		OUTPUT ${PACKAGE_WORKING_DIR}/pyproject.toml
+		CONTENT "${PYPROJECT_CONTENT}"
+	)
+
+	# Define packaging target
+	add_custom_target (
+		package_wheel_${PACK_WHL_TARGET_NAME}
+		# Ensure package directory exists
+		COMMAND ${CMAKE_COMMAND} -E make_directory "${PACKAGE_WORKING_DIR}"
+		# Copy executable to package directory
+		COMMAND ${CMAKE_COMMAND} -E copy "$<TARGET_FILE:${PACK_WHL_TARGET_NAME}>"
+				"${PACKAGE_INIT_DIR}/$<TARGET_FILE_NAME:${PACK_WHL_TARGET_NAME}>"
+		# copy all shared libraries to the package directory
+		COMMAND ${CMAKE_COMMAND} -E copy -t ${PACKAGE_INIT_DIR} $<TARGET_RUNTIME_DLLS:${PACK_WHL_TARGET_NAME}>
+		# Ensure wheel is installed
+		COMMAND ${Python3_EXECUTABLE} -m pip install --upgrade wheel build
+		# Build the wheel using pyproject.toml
+		COMMAND ${Python3_EXECUTABLE} -m build --wheel
+		WORKING_DIRECTORY "${PACKAGE_WORKING_DIR}"
+		COMMENT "Generating Python wheel for ${PACK_WHL_TARGET_NAME} ..."
+		COMMAND_EXPAND_LISTS
+	)
+	# make this target depend on the build target
+	add_dependencies (package_wheel_${PACK_WHL_TARGET_NAME} ${PACK_WHL_TARGET_NAME})
+
+	# put the target in an IDE folder
+	set_property (TARGET package_wheel_${PACK_WHL_TARGET_NAME} PROPERTY FOLDER "package_wheel")
+
+	if (PACK_WHL_OUTPUT_VAR)
+		set (
+			${PACK_WHL_OUTPUT_VAR}
+			${DIST_DIR}
+			PARENT_SCOPE
+		)
+	endif ()
+
+endfunction ()