modern-cmake/chapters/testing/catch.md

Catch

Catch and Catch2 (C++11 only version) are powerful, idomatic testing solutions similar in philosophy to PyTest for Python. To use Catch in a CMake project, there are several options.

Vendoring

If you simply drop in the single include release of Catch into your project, this is what you would need to add Catch:

# Prepare "Catch" library for other executables
set(CATCH_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/extern/catch)
add_library(Catch2::Catch IMPORTED INTERFACE)
set_property(Catch2::Catch PROPERTY INTERFACE_INCLUDE_DIRECTORIES "${CATCH_INCLUDE_DIR}")

Then, you would link to Catch2::Catch. This would have been okay as an INTERFACE target since you won't be exporting your tests.

Direct inclusion

If you add the library using ExternalProject, FetchContent, or git submodules, you can also add_subdirectory Catch (CMake 3.1+).

Catch also provides two CMake modules that you can use to register the individual tests with CMake.