How to pass command-line arguments in CTest at runtime

Question

I'm using CTest and want to pass command-line arguments to the underlying tests at runtime. I know there are ways to hard code command-line arguments into the CMake/CTest script, but I want to specify the command-line arguments at runtime and have those arguments passed through CTest to the underlying test.

Is this even possible?

Answer 1

I've figured out a way to do it (using the Fundamental theorem of software engineering). It's not as simple as I'd like, but here it is.

First, create a file ${CMAKE_SOURCE_DIR}/cmake/RunTests.cmake with the content

if(NOT DEFINED ENV{TESTS_ARGUMENTS})     set(ENV{TESTS_ARGUMENTS} "--default-arguments") endif() execute_process(COMMAND ${TEST_EXECUTABLE} $ENV{TESTS_ARGUMENTS} RESULT_VARIABLE result) if(NOT "${result}" STREQUAL "0")     message(FATAL_ERROR "Test failed with return value '${result}'") endif() 

Then, when you add the test, use

add_test(     NAME MyTest     COMMAND ${CMAKE_COMMAND} -DTEST_EXECUTABLE=$<TARGET_FILE:MyTest> -P ${CMAKE_SOURCE_DIR}/cmake/RunTests.cmake ) 

Finally, you can run the test with custom arguments using

cmake -E env TESTS_ARGUMENTS="--custom-arguments" ctest 

Note that if you use bash, you can simplify this to

TESTS_ARGUMENTS="--custom-arguments" ctest 

There are some problems with this approach, e.g. it ignores the WILL_FAIL property of the tests. Of course I wish it could be as simple as calling ctest -- --custom-arguments, but, as the Stones said, You can't always get what you want.