Python system path installation wrong directory

[oysstu]

Enabling the USE_SYSTEM_PATHS_FOR_PYTHON_INSTALLATION option installs the python libraries in a folder called gz in the system root. The other libraries, such as gz-msgs and gz-math, installs their libraries in the correct location using this option.

I suppose the following part is the problem

gz-sim/python/CMakeLists.txt

Lines 9 to 32 in ab0669c

	if(USE_SYSTEM_PATHS_FOR_PYTHON_INSTALLATION)
	if(${CMAKE_VERSION} VERSION_LESS "3.12.0")
	execute_process(
	COMMAND "${PYTHON_EXECUTABLE}" -c "if True:
	from distutils import sysconfig as sc
	print(sc.get_python_lib(plat_specific=True))"
	OUTPUT_VARIABLE Python3_SITEARCH
	OUTPUT_STRIP_TRAILING_WHITESPACE)
	else()
	# Get install variable from Python3 module
	# Python3_SITEARCH is available from 3.12 on, workaround if needed:
	find_package(Python3 COMPONENTS Interpreter)
	endif()
	if(USE_DIST_PACKAGES_FOR_PYTHON)
	string(REPLACE "site-packages" "dist-packages" GZ_PYTHON_INSTALL_PATH ${Python3_SITEARCH})
	endif()
	else()
	# If not a system installation, respect local paths
	set(GZ_PYTHON_INSTALL_PATH ${GZ_LIB_INSTALL_DIR}/python)
	endif()
	set(GZ_PYTHON_EXECUTABLE ${Python3_EXECUTABLE})
	set(GZ_PYTHON_INSTALL_PATH "${GZ_PYTHON_INSTALL_PATH}/gz")

The equivalent part in gz-math. The else statement in USE_DIST_PACKAGES_FOR_PYTHON seem to be missing?
https://github.com/gazebosim/gz-math/blob/a527e1422c25df73e30ee4f0c38ccbe56f6da4e4/src/python_pybind11/CMakeLists.txt#L75-L100

[azeey]

Hi @oysstu, thanks for filing an issue! Since you've already identified what needs to be done, would you mind creating a PR?

[oysstu]

Hi @oysstu, thanks for filing an issue! Since you've already identified what needs to be done, would you mind creating a PR?

Opened in #2274. With this, python libraries are installed to /usr/lib/python3.XX/site-packages/gz/ instead of /gz.