c++ - 将 google test 集成到现有 CMake 项目时出错

Question

我有一个工作项目，我想将 google test 添加到其中，但有一个区别是，我的 main() 函数在不同的文件中。

这是我的项目结构:

-test
    - include
        - file.h
        - file1.h
        - file2.h
    - file.cpp
    - file1.cpp
    - file2.cpp
    - main.cpp
    - CMakeLists.txt
    - unitTest
        -CMakeLists.txt
        -test_main.cpp

我的 main CMakeLists.txt 文件链接了很多 test_main.cpp 也需要的库和文件，但它也会创建一个可执行文件。我尝试使用这个 question但我不知道如何让它工作，甚至不知道如何让它工作。

这是我的unitTest/CMakeList.txt:

cmake_minimum_required(VERSION 3.14)
# Download and unpack googletest at configure time
project(Google_tests)
configure_file(CMakeLists.txt.in googletest-download/CMakeLists.txt)
execute_process(COMMAND ${CMAKE_COMMAND} -G "${CMAKE_GENERATOR}" .
        RESULT_VARIABLE result
        WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/googletest-download )
if(result)
    message(FATAL_ERROR "CMake step for googletest failed: ${result}")
endif()
execute_process(COMMAND ${CMAKE_COMMAND} --build .
        RESULT_VARIABLE result
        WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/googletest-download )
if(result)
    message(FATAL_ERROR "Build step for googletest failed: ${result}")
endif()

set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)

add_subdirectory(${CMAKE_CURRENT_BINARY_DIR}/googletest-src
        ${CMAKE_CURRENT_BINARY_DIR}/googletest-build
        EXCLUDE_FROM_ALL)

if (CMAKE_VERSION VERSION_LESS 2.8.11)
    include_directories("${gtest_SOURCE_DIR}/include")
endif()

# Now simply link against gtest or gtest_main as needed. Eg

include(${CMAKE_CURRENT_SOURCE_DIR}/../CMakeLists.txt)
add_executable(Google_tests test_main.cpp)
target_link_libraries(Google_tests gtest gtest_main)
add_test(NAME example_test COMMAND Google_tests)

此 CMakeList 文件来自 google test git hub ，我也尝试做 Clion 手册 wrote ,但它仍然无法正常工作。这是我得到的错误:

-- Configuring done 
CMake Error at /home/yaodav/Desktop/dnr_main_repo/test/CMakeLists.txt:74 (add_executable):   
  Cannot find source file:

    main.cpp

  Tried extensions .c .C .c++ .cc .cpp .cxx .cu .m .M .mm .h .hh .h++ .hm   .hpp .hxx .in .txx 
Call Stack (most recent call first):   
  CMakeLists.txt:30 (include)

CMake Error at /home/yaodav/Desktop/dnr_main_repo/test/CMakeLists.txt:74 (add_executable):   
  No SOURCES given to target: test 
Call Stack (most recent call first):   
  CMakeLists.txt:30 (include)
CMake Generate step failed.  Build files cannot be regenerated correctly.

这是测试/CMakeList.txt:

cmake_minimum_required(VERSION 3.14)
project(test)
set(CMAKE_CXX_STANDARD 17)
if (CMAKE_BUILD_TYPE MATCHES Release)
    add_definitions(-DRELEASE=1)
    add_definitions(-DDEBUG=0)
    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O2")
else()
    add_definitions(-DRELEASE=0)
    add_definitions(-DDEBUG=1)
endif ()

include_directories(/include)


link_directories(list of dir)

#link_libraries(../lib/external/tinyxml2-master)
find_package(Threads) # for enableing std::thread
find_library(conn_LIB connlib)

SET(SOURCE_FILES main.cpp
      file.cpp file.h
      file1.cpp file1.h
      file2.cpp file2.h )
add_executable(test ${SOURCE_FILES})

SET(LBS list of libs)

target_link_libraries(test ${list of libs} pq)

Answer 1

unitTest/CMakeLists.txt 文件中的以下行会导致您可能无法预料的行为:

include(${CMAKE_CURRENT_SOURCE_DIR}/../CMakeLists.txt)

来自 include 的文档，此命令将:

Load and run CMake code from a file or module.

此命令通常保留用于加载 CMake Find Modules或其他自定义 CMake 模块(即 *.cmake 文件)。因此，这不会更改当前的 CMake 源目录，因此 test/CMakeLists.txt 中提到的文件仍相对于子目录 test/unitTest。调用 include() 后，CMake 在 test/unitTest 中查找 main.cpp 文件(和其他文件)，但它不存在。因此，CMake 打印错误。

虽然不推荐，但如果你确实需要像这样遍历父CMakeLists.txt文件(使用include())，你可以使用CMAKE_CURRENT_LIST_DIR引用源文件:

SET(SOURCE_FILES 
    ${CMAKE_CURRENT_LIST_DIR}/main.cpp
    ${CMAKE_CURRENT_LIST_DIR}/file.cpp
    ${CMAKE_CURRENT_LIST_DIR}/include/file.h
    ${CMAKE_CURRENT_LIST_DIR}/file1.cpp 
    ${CMAKE_CURRENT_LIST_DIR}/include/file1.h
    ${CMAKE_CURRENT_LIST_DIR}/file2.cpp 
    ${CMAKE_CURRENT_LIST_DIR}/include/file2.h 
)
add_executable(test ${SOURCE_FILES})

您可能需要对 test/CMakeLists.txt 文件中的其他相对 引用进行类似的更改，以防止这种异常方法导致的错误。

---

我的建议是改为从您的顶层 CMakeLists.txt 文件运行 CMake，并简单地使用以下行遍历到子目录中的 CMake 文件:

add_subdirectory(unitTest)