making sure env-hooks have all variables setup before adding.

cmake/catkin-pip.cmake.in

@@ -26,14 +26,15 @@ if ( NOT CATKIN_PIP_ENV_HOOKS_PATH )
     set (CATKIN_PIP_ENV_HOOKS_PATH ${CMAKE_CURRENT_LIST_DIR}/env-hooks)
 endif()
 
-# Since we need the envhook as soon as a package is using catkin-pip from source, but only in devel space
-catkin_add_env_hooks(42.site_packages SHELLS bash DIRECTORY ${CATKIN_PIP_ENV_HOOKS_PATH})
-# TODO : cmake should include this file only once, so the env hook is not recreated for every package that includes it...
-
 # We want the catkin environment to be used for both devel and install workspace
 # to use latest versions python tools in both.
 set(CATKIN_PIP_ENV ${CMAKE_BINARY_DIR}/catkin_pip_env CACHE PATH "The path containing the python environment for catkin_pip dependencies" )
 set(CATKIN_PIP_PYTHON_INSTALL_DIR @CATKIN_PIP_GLOBAL_PYTHON_DESTINATION@)
+
+# Since we need the envhook as soon as a package is using catkin-pip from source, but only in devel space
+catkin_add_env_hooks(42.site_packages SHELLS bash DIRECTORY ${CATKIN_PIP_ENV_HOOKS_PATH})
+# TODO : cmake should include this file only once, so the env hook is not recreated for every package that includes it...
+
 catkin_pip_setup_prefix(${CATKIN_PIP_ENV})
 
 #