Using conan for unit tests

[kammce]

Whats the preferred way to us conan libraries for unit tests. For example, my only dependencies for my library tests are the library itself and boost::ut.

My previous naive approach for this was just to have a conanfile.txt:

[requires]
libarmcortex/[>=0.0.1]
boost-ext-ut/1.1.8

[generators]
cmake_find_package_multi

And my CMakeLists.txt file looked like:

cmake_minimum_required(VERSION 3.1...3.21)

project(test VERSION 0.0.1 LANGUAGES CXX)

list(APPEND CMAKE_MODULE_PATH ${CMAKE_BINARY_DIR})
list(APPEND CMAKE_PREFIX_PATH ${CMAKE_BINARY_DIR})

find_package(libarmcortex CONFIG REQUIRED)
find_package(ut CONFIG REQUIRED)

add_executable(${PROJECT_NAME}
    system_timer.test.cpp
    dwt_counter.test.cpp
    interrupt.test.cpp
    main.test.cpp)

target_compile_features(${PROJECT_NAME} PRIVATE cxx_std_20)
set_target_properties(${PROJECT_NAME} PROPERTIES CXX_EXTENSIONS OFF)
target_compile_definitions(${PROJECT_NAME} PRIVATE -DPLATFORM=test)
target_link_libraries(${PROJECT_NAME} PRIVATE
    libarmcortex::libarmcortex
    boost::ut)

I ran conan install .., cmake .., make, and ./test from a build folder within the tests/ directory and not from the top level. I'm not sure if that's the right approach though when it comes to using cmake-init.

[friendlyanon]

The Conan example from the README shows you how to integrate with Conan. It also shows you how to use a dev dependency, such as doctest. To costumize how Conan installs your dependencies, you can edit the conan.cmake file.

If you follow the example, then you have an experience similar to vcpkg:

cmake --preset=dev-unix # the preset also has the Conan code
cmake --build build/dev-unix
ctest --test-dir build/dev-unix

[kammce]

Would this be where the dependencies are listed? https://github.com/friendlyanon/cmake-init-conan-example/blob/master/cmake/conan.cmake#L45

Does that mean that using a conanfile.txt or conanfile.py is discouraged? And if so, how does something like conan create . get utilized in order to generate/locally install packages?

[friendlyanon]

It's not discouraged, but I have not yet found a way to express dev dependencies in conanfiles. Delegating the invocation of Conan to cmake-conan allows you to have requirements hidden behind an option. This sort of mimics vcpkg's "features" feature.