Fix support for consuming YCM via FetchContent_MakeAvailable

Author: traversaro

CMakeLists.txt

@@ -3,12 +3,16 @@
 
 
 cmake_minimum_required(VERSION 3.16)
-project(YCM VERSION 0.17.0 LANGUAGES NONE)
+project(YCM VERSION 0.17.1 LANGUAGES NONE)
 
 # Check if the project is the main project or included via FetchContent
 if (NOT CMAKE_SOURCE_DIR STREQUAL PROJECT_SOURCE_DIR)
     # Project is included via FetchContent
     include(${CMAKE_CURRENT_SOURCE_DIR}/tools/UseYCMFromSource.cmake)
+    # Propagate relevant variables modified by UseYCMFromSource to who called add_subdirectory
+    set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} PARENT_SCOPE)
+    set(__USEYCMFROMSOURCE_INCLUDED ${__USEYCMFROMSOURCE_INCLUDED} PARENT_SCOPE)
+    set(YCM_MODULE_DIR ${YCM_MODULE_DIR} PARENT_SCOPE)
     return()
 endif()