CMake: add additional target to run clang-tidy only in the differing files

    ELSE()

        MESSAGE(STATUS "Could NOT find run-clang-tidy script")

    ENDIF()

    # Add targets for differing files only, directly calling clang-tidy

    IF(NOT TARGET_BRANCH)

        SET(TARGET_BRANCH "master")

    ENDIF()

    EXEC_PROGRAM(

        git ${CMAKE_PROJECT_SOURCE_DIR}

        ARGS diff origin/${TARGET_BRANCH} --name-only --line-prefix=`git rev-parse --show-toplevel`/

        OUTPUT_VARIABLE changed_files

        RETURN_VALUE retval)

    IF(NOT retval)

        STRING(REPLACE "\n" ";" changed_files "${changed_files}")

        SET(COMMANDS)

        FOREACH(srcfile ${changed_files})

            IF("${srcfile}" IN_LIST CHECK_CXX_SOURCE_FILES)

                LIST(

                    APPEND

                    COMMANDS

                    COMMAND

                    ${CLANG_TIDY}

                    --config-file=${CMAKE_SOURCE_DIR}/.clang-tidy

                    --header-filter=${CMAKE_SOURCE_DIR}

                    --use-color

                    -p=${CMAKE_BINARY_DIR}

                    ${srcfile}

                    | tee -a ${CMAKE_BINARY_DIR}/check_lint_diff_file.txt)

            ENDIF()

        ENDFOREACH()

        ADD_CUSTOM_TARGET(

            check-lint-diff

            COMMAND > ${CMAKE_BINARY_DIR}/check_lint_diff_file.txt ${COMMANDS}

            COMMAND ! grep -c ": error: " ${CMAKE_BINARY_DIR}/check_lint_diff_file.txt > /dev/null

            COMMENT "Checking for problems in source files")

    ENDIF()

ELSE()

    IF(CMAKE_CXX_COMPILER_ID STREQUAL "Clang")

        MESSAGE(STATUS "Could NOT find clang-tidy version ${CLANG_FORMAT_VERSION}")