CMake Installation -- FindUPCXX.cmake vs. UPCXXConfig.cmake

I am wondering why UPC++ installs both a FindUPCXX.cmake and UPCXXConfig.cmake. I realize that UPCXXConfig.cmake just contains: include(${CMAKE_CURRENT_LIST_DIR}/FindUPCXX.cmake). Standard CMake practices are such that a package that installs via CMake, provides a <PackageName>Config.cmake (or <PackageName>-config.cmake) for find_package(<PackageName>) and a package that does not use CMake uses a Find<PackageName>.cmake. And the default CMake behavior is to search for both Find<PackageName>.cmake and <PackageName>Config.cmake so, at a minimum, providing both is redundant.

However, if you read the details of find_package in the CMake documentation, you will find there exist an options for find_package(<PackageName> MODULE) and a CMAKE_FIND_PACKAGE_PREFER_CONFIG variable that allow for specification for whether the Find<PackageName>.cmake and <PackageName>Config.cmake are preferred (or exclusively searched for) so, by providing both, the UPC++ installation at both is seemingly making it slightly more complicated for a package to provide it’s own FindUPCXX.cmake, if so desired, without any clear reason, e.g.:

If a package provided it’s own FindUPCXX.cmake, this would find the UPC++ installed version instead of their own:

set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} ${PROJECT_SOURCE_DIR}/cmake/Modules)
# ...
find_package(UPCXX MODULE)

while this would find their own:

set(CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/cmake/Modules ${CMAKE_MODULE_PATH})
# ...
find_package(UPCXX MODULE)

but a project may have a reason for keeping the ${CMAKE_MODULE_PATH} before their local module file and there is nothing can be done in this situation except something like:

set(ORIG_MODULE_PATH ${CMAKE_MODULE_PATH})
# temporarily change to work-around UPC++
set(CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/cmake/Modules ${ORIG_MODULE_PATH})
find_package(UPCXX MODULE)
# revert to desired setup
set(CMAKE_MODULE_PATH ${ORIG_MODULE_PATH} ${PROJECT_SOURCE_DIR}/cmake/Modules)

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