这篇文章有一个合理的答案：
CMakeLists.txt.in：
cmake_minimum_required(VERSION 2.8.2)
project(googletest-download NONE)
include(ExternalProject)
ExternalProject_Add(googletest
GIT_REPOSITORY https://github.com/google/googletest.git
GIT_TAG master
SOURCE_DIR "${CMAKE_BINARY_DIR}/googletest-src"
BINARY_DIR "${CMAKE_BINARY_DIR}/googletest-build"
CONFIGURE_COMMAND ""
BUILD_COMMAND ""
INSTALL_COMMAND ""
TEST_COMMAND ""
)
CMakeLists.txt：
# Download and unpack googletest at configure time
configure_file(CMakeLists.txt.in
googletest-download/CMakeLists.txt)
execute_process(COMMAND ${CMAKE_COMMAND} -G "${CMAKE_GENERATOR}" .
WORKING_DIRECTORY ${CMAKE_BINARY_DIR}/googletest-download )
execute_process(COMMAND ${CMAKE_COMMAND} --build .
WORKING_DIRECTORY ${CMAKE_BINARY_DIR}/googletest-download )
# Prevent GoogleTest from overriding our compiler/linker options
# when building with Visual Studio
set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)
# Add googletest directly to our build. This adds
# the following targets: gtest, gtest_main, gmock
# and gmock_main
add_subdirectory(${CMAKE_BINARY_DIR}/googletest-src
${CMAKE_BINARY_DIR}/googletest-build)
# The gtest/gmock targets carry header search path
# dependencies automatically when using CMake 2.8.11 or
# later. Otherwise we have to add them here ourselves.
if (CMAKE_VERSION VERSION_LESS 2.8.11)
include_directories("${gtest_SOURCE_DIR}/include"
"${gmock_SOURCE_DIR}/include")
endif()
# Now simply link your own targets against gtest, gmock,
# etc. as appropriate
但是，它似乎确实很hacky。我想提出一个替代解决方案-使用Git子模块。
cd MyProject/dependencies/gtest
git submodule add https://github.com/google/googletest.git
cd googletest
git checkout release-1.8.0
cd ../../..
git add *
git commit -m "Add googletest"
然后，MyProject/dependencies/gtest/CMakeList.txt您可以执行以下操作：
cmake_minimum_required(VERSION 3.3)
if(TARGET gtest) # To avoid diamond dependencies; may not be necessary depending on you project.
return()
endif()
add_subdirectory("googletest")
我还没有广泛尝试过，但是看起来更干净。
编辑：这种方法有一个缺点：子目录可能运行install()您不想要的命令。这篇文章有一种禁用它们的方法，但是它有很多错误，对我不起作用。
编辑2：如果您使用add_subdirectory("googletest" EXCLUDE_FROM_ALL)它，则意味着install()默认情况下未使用子目录中的命令。