Trouble setting environment variables for CTest tests

Question

I\'m tasked with building python bindings for a c++-based project (using swig). The project uses cmake to build and ctest to test and the build and test of the bindings are

Answer 1

Craig Scott already provided a great solution via ENVIRONMENT test properties. I just want to add how this works on Windows with the Visual Studio generator and generator expressions:

set_tests_properties(
    name_of_test_one
    name_of_test_two
PROPERTIES
    # Make sure DLL is found by adding its directory to PATH
    ENVIRONMENT "PATH=$<TARGET_FILE_DIR:library_target_name>\;$ENV{PATH}"
)

Note 1: Instead of a colon, use an escaped semi-colon Note 2: I'm using the more flexible $ generator expression

Answer 2

You can set environment variables as part of invoking the test by using the cmake -E env command. You can modify the add_test() call to something like the following:

ADD_TEST(NAME testPyMyproj
    COMMAND ${CMAKE_COMMAND} -E env
        LD_LIBRARY_PATH=${CMAKE_BINARY_DIR}/lib:$ENV{LD_LIBRARY_PATH}
        ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/test_scripts/test_pyMyproj.py
)

The above assumes a Unix-based host environment, but you could generalise this to support all platforms/generator types with a bit of work if you needed to.

Another alternative is to use the ENVIRONMENT test property which should achieve essentially the same thing:

set_tests_properties(testPyMyproj PROPERTIES
    ENVIRONMENT LD_LIBRARY_PATH=${CMAKE_BINARY_DIR}/lib:$ENV{LD_LIBRARY_PATH})