catch_discover_tests() DL_PATHS can't handle two or more paths

[SolomidHero]

Describe the bug
I am trying to specify shared libs paths to tests. It was fine for 1 library to add it to DL_PATHS of catch_discover_tests(), but adding more paths has no effect.

catch_discover_tests(Tests
    DL_PATHS
        "${path_to_A}/lib"
        "${path_to_B}/lib"  # test executable won't use it
)

I understood it with some tricky logic:

• Library A is 3rd party and no such on system.
• Library B is 3rd party too, but system has it analog with a little changed functionality (say older version). So without providing path B my executable runs, but fails internally.

When running ctest --verbose I saw:

...
1: Working Directory: C:/Users/Administrator/Project/build
1: Environment variable modifications:
1:  PATH=path_list_prepend:C:\Users\Administrator\Project\build\path\to\A\lib 
...

see only one lib in PATH, but DL_PATHS provided with 2.

Expected behavior

Test executable would have PATH prefixed with all paths provided in DL_PATHS parameter of catch_discover_tests()

Reproduction steps
You can try having small repro with such

enable_testing()

include(FetchContent)
FetchContent_Declare(
    Catch2
    GIT_REPOSITORY https://github.com/catchorg/Catch2.git
    GIT_PROGRESS TRUE
    GIT_SHALLOW TRUE
    GIT_TAG v3.4.0 # I used this version
)
FetchContent_MakeAvailable(Catch2)

# define test executable and link shared/imported libs
...


catch_discover_tests(Tests
    EXTRA_ARGS ${TEST_ARGS}
    DL_PATHS
        "$Env{PATH}"
        "${path_to_A}/lib")

i.e. I added needed library after some placeholder. It won't work either

Platform information:

• OS: Windows 10.0.20348.0
• Compiler+version: MSVC 17 19.36.32532.0
• Catch version: v3.4.0
• cmake 3.26.4

Additional context
I see DL_PATHS passed somewhere on POST_BUILD branch:

-D "TEST_DL_PATHS=${_DL_PATHS}"

[daniel-slater]

This happens because the call to cmake_parse_arguments() inside function(catch_discover_tests_impl) in CatchAddTests.cmake has TEST_DL_PATHS in the one-value keywords list, instead of the multi-value keywords list.

[LecrisUT]

@daniel-slater I am not sure about that, in CatchAddTests.cmake, it is parsed inside as:

cmake_path(CONVERT "${dl_paths}" TO_NATIVE_PATH_LIST paths)

So dl_paths should have escaped ; or :. I am not sure if it gets double escaped in this case.

But btw, there is a more easier approach to DL_PATHS using TARGET_RUNTIME_DLL_DIRS. I will write a simple PR to add this for CMake >= 3.27

Edit: Actually you are right about the multi-value, I did a quick test with it and indeed it succeeded. It even worked as a gen-ex: DL_PATHS "$<TARGET_RUNTIME_DLL_DIRS:test-suite>"