Extract sources list for the test binary into a CMake variable

ChaosTests/CMakeLists.txt

@@ -11,7 +11,10 @@ FetchContent_Declare(
 set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)
 FetchContent_MakeAvailable(googletest)
 
-add_executable(ChaosTests Md4HasherTests.cpp Md5HasherTests.cpp)
+set(ChaosTests_SOURCE Md4HasherTests.cpp
+                      Md5HasherTests.cpp)
+
+add_executable(ChaosTests ${ChaosTests_SOURCE})
 target_link_libraries(ChaosTests gtest gtest_main)
 target_include_directories(ChaosTests PRIVATE
     $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/Chaos>