CMake testing problems

[pdimov]

I took a closer look at the CMake testing problem, whose most recent manifestation was this

[ 81%] Building CXX object libs/math/test/compile_test/CMakeFiles/boost_math-compile_tests.dir/tools_test_inc_test.cpp.o
In file included from /home/runner/work/cmake/boost-root/libs/math/test/compile_test/tools_test_inc_test.cpp:12:
/home/runner/work/cmake/boost-root/libs/math/test/compile_test/../../include_private/boost/math/tools/test.hpp:19:10: fatal error: boost/test/test_tools.hpp: No such file or directory
   19 | #include <boost/test/test_tools.hpp>
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~

(https://github.com/boostorg/cmake/actions/runs/11310512254/job/31455650803)

because I wondered why this doesn't also appear in the superproject CI which also invokes the CMake tests (https://github.com/boostorg/boost/actions/runs/11310570697/job/31455773234).

It turns out that this is because the compile tests are added here

https://github.com/boostorg/math/blob/522989011aca84e375e71b3a571007c2fbb9bd6d/test/compile_test/CMakeLists.txt

directly (without using boost_test), which makes them (a) not dependencies of the tests target, which is what the Boost documented testing procedure builds (https://github.com/boostorg/cmake#testing-boost-with-cmake), and (b) included in the "all" target that is built by default by make or cmake --build .. (By Boost convention tests aren't included in "all", which makes it possible to build only the libraries even when testing is enabled.)

The end result of all this is that cmake --build . --target tests works, because the compile tests are simply not built. Since those are compile-only, that's not a problem for the subsequent ctest invocation because there's nothing to run.

cmake --build ., however, fails when testing is enabled, because it does build the compile tests, and they fail.

So...

If you want to keep building the compile tests on cmake --build . but not on cmake --build . --target tests, you have to add include_directories(../../include_private) to test/compile_test/CMakeLists.txt;

If you want to manually fix them to be built on cmake --build . --target tests but not cmake --build . per convention, you have to use add_dependencies manually to attach them to the tests target and use EXCLUDE_FROM_ALL and also add the include_directories fix;

Or you can switch to using boost_test, which will take care of the tests target and EXCLUDE_FROM_ALL, in which case you can use its INCLUDE_DIRECTORIES argument instead of include_directories.

(There's also the option of setting BOOST_TEST_INCLUDE_DIRECTORIES in test/CMakeLists.txt, which will apply to all subsequent boost_test and boost_test_jamfile invocations, but make sure to set it to an absolute path.)

[pdimov]

(Actually the current error is caused not by missing include_directories but because the compile tests don't link to Boost::unit_test_framework.)

[mborland]

Is there a way to glob with boost_test? It get an error with the following change to test/compile_test/CMakeLists.txt

include_directories(../../include_private)
file(GLOB SRC_FILES "*.cpp")
boost_test(SOURCES SRC_FILES COMPILE_FEATURES cxx_std_17 LINK_LIBRARIES Boost::math Boost::multiprecision Boost::numeric_ublas Boost::unit_test_framework )

The error is:

CMake Error at tools/cmake/include/BoostTest.cmake:242 (add_executable):
  Cannot find source file:

    SRC_FILES

  Tried extensions .c .C .c++ .cc .cpp .cxx .cu .mpp .m .M .mm .ixx .cppm
  .ccm .cxxm .c++m .h .hh .h++ .hm .hpp .hxx .in .txx .f .F .for .f77 .f90
  .f95 .f03 .hip .ispc
Call Stack (most recent call first):
  libs/math/test/compile_test/CMakeLists.txt:7 (boost_test)

CMake Error at tools/cmake/include/BoostTest.cmake:242 (add_executable):
  No SOURCES given to target: boost_math-SRC_FILES
Call Stack (most recent call first):
  libs/math/test/compile_test/CMakeLists.txt:7 (boost_test)

[pdimov]

Should be boost_test(SOURCES ${SRC_FILES} ... to expand the variable. Also, probably add CONFIGURE_DEPENDS to the glob.

You can also use foreach(src IN LISTS SRC_FILES) if you want to add individual tests instead of one, although in this case it probably doesn't matter.