doctest_discover_tests and FetchContent_Declare

[ChristofferGreen]

Hi

Using FetchContent_Declare/FetchContent_MakeAvailable it's possible to download doctest and use it from cmake without having it pre-installed or packaged with your project.

It's not clear to me however how to use the doctest_discover_tests functionality https://github.com/onqtam/doctest/blob/master/scripts/cmake/doctest.cmake when using FetchContent_Declare/FetchContent_MakeAvailable. Does anyone know?

The closest I have gotten is to do:
include(${doctest_SOURCE_DIR}/scripts/cmake/doctest.cmake)
doctest_discover_tests(ProjectName)

But -P "${_DOCTEST_DISCOVER_TESTS_SCRIPT}" does not get set correctly.

Thank you

[onqtam]

Perhaps its similar to what one would do when using Catch2. However, I'm not familiar so I'd appreciate it if someone else helps out with this.

[ChristofferGreen]

This eventually started working. Posting current solution here incase anyone else has the same issue. Not sure what the solution ended up being. I think I had some random issue that solved itself, sorry about that.

------------------------------------ First fetch/config doctest:
FetchContent_Declare(doctest GIT_REPOSITORY https://github.com/onqtam/doctest GIT_TAG 2.3.7)
FetchContent_MakeAvailable(doctest)
------------------------------------  Add libs/includes etc, just how I do it in my project, will be different for others
list(APPEND PMDepIncludesPublic ${doctest_SOURCE_DIR}/doctest)
list(APPEND PMDepLibraries      doctest)
set(PMDepLibraries      ${PMDepLibraries}      PARENT_SCOPE)
set(PMDepIncludesPublic ${PMDepIncludesPublic} PARENT_SCOPE)
------------------------------------  Main things
enable_testing()
include(${doctest_SOURCE_DIR}/scripts/cmake/doctest.cmake)
doctest_discover_tests(Dygd)

[stephenlevitt]

@ChristofferGreen I have followed your approach and have managed to produce a valid CMake file which contains doctest_discover_tests - thanks! Unfortunately, now I am getting an error in that the text executable cannot be run:

[build] [ 58%] Linking CXX executable bin\Tests.exe
[build] CMake Error at _deps/doctest-src/scripts/cmake/doctestAddTests.cmake:45 (message):
[build]   Error running test executable
[build]   'C:/Data/...Project/build/bin/Tests.exe':
[build] 
[build] 
[build]     Result: Exit code 0xc0000139

If I remove doctest_discover_tests and just build the test exe target, the tests run without a problem. Do you have any idea how to fix this?

[ChristofferGreen]

It sounds like there is some error in the c++ code, the error message says that main is returning 0xc0000139, anything above 0 is an error.

[stephenlevitt]

@ChristofferGreen Thanks for your comment. I'm confused because no error is produced when I run my test executable. The test file cannot be run only when I attempt to use doctest_discover_tests.

Here is minimal example of a CMakeLists.txt file illustrating the problem (see the last line). I have used the factorial function from the doctest homepage. I am running on Windows 10, using VS Code:

message("Processing CMakeLists.txt...")

cmake_minimum_required(VERSION 3.27.1)
project(example-project)

# ====================== Setup Targets ======================

# Test executable
add_executable(factorial-tests ${CMAKE_SOURCE_DIR}/factorial.cpp)
target_link_libraries(factorial-tests PRIVATE doctest::doctest) # link publicly to make doctest headers available to the target

# ====================== Declare and Download Dependencies ======================

include(FetchContent)

# doctest
FetchContent_Declare(
    doctest
    GIT_REPOSITORY https://github.com/doctest/doctest.git
    # corresponds to doctest v2.4.11 - good practice to specify the commit hash as tags can be moved
    GIT_TAG "ae7a13539fb71f270b87eb2e874fbac80bc8dda2" )

# make the dependencies available to the build system
FetchContent_MakeAvailable(doctest)

# ====================== CTest ======================

enable_testing()
include(${doctest_SOURCE_DIR}/scripts/cmake/doctest.cmake)
# doctest_discover_tests(factorial-tests) # uncommenting this line causes the error

[stephenlevitt]

Here is factorial.cpp (in the same directory at CMakeLists.txt):

#define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
#include "doctest/doctest.h"

int factorial(int number) { return number <= 1 ? number : factorial(number - 1) * number; }

TEST_CASE("testing the factorial function")
{
    CHECK(factorial(0) == 1);
    CHECK(factorial(1) == 1);
    CHECK(factorial(2) == 2);
    CHECK(factorial(3) == 6);
    CHECK(factorial(10) == 3628800);
}

Output with the last line commented:

$ "C:/Data/.../factorial-project/build/factorial-tests.exe"
[doctest] doctest version is "2.4.11"
[doctest] run with "--help" for options
===============================================================================
C:\Data\...\factorial-project\factorial.cpp:6:
TEST CASE:  testing the factorial function

C:\Data\...\factorial-project\factorial.cpp:8: ERROR: CHECK( factorial(0) == 1 ) is NOT correct!     
  values: CHECK( 0 == 1 )

===============================================================================
[doctest] test cases: 1 | 0 passed | 1 failed | 0 skipped
[doctest] assertions: 5 | 4 passed | 1 failed |
[doctest] Status: FAILURE!

Output with the last line uncommented:

[main] Building folder: factorial-project all
[build] Starting build
[proc] Executing command: "C:\Program Files\CMake\bin\cmake.EXE" --build c:/Data/.../factorial-project/build --config Debug --target all -j 14 --
[build] [ 50%] Linking CXX executable factorial-tests.exe
[build] CMake Error at _deps/doctest-src/scripts/cmake/doctestAddTests.cmake:45 (message):
[build]   Error running test executable
[build]   'C:/Data/.../factorial-project/build/factorial-tests.exe':
[build] 
[build] 
[build]     Result: Exit code 0xc0000139
[build] 
[build]   
[build] 
[build]     Output: 
[build] 
[build] 
[build] 
[build] mingw32-make[2]: *** [CMakeFiles\factorial-tests.dir\build.make:100: factorial-tests.exe] Error 1
[build] mingw32-make[2]: *** Deleting file 'factorial-tests.exe'
[build] mingw32-make[1]: *** [CMakeFiles\Makefile2:99: CMakeFiles/factorial-tests.dir/all] Error 2
[build] mingw32-make: *** [Makefile:145: all] Error 2
[proc] The command: "C:\Program Files\CMake\bin\cmake.EXE" --build c:/Data/.../factorial-project/build --config Debug --target all -j 14 -- exited with code: 2
[driver] Build completed: 00:00:01.281
[build] Build finished with exit code 2