When writing gtests with ROS, why doesn't the FRIEND_TEST macro work? [closed]

edit

For unit testing, I need to write gtests that can access at least some private data. The FRIEND_TEST macro doesn't seem to be working however. In the example here, I have my so-called "targetClass" whose privateMap I wish to access. This has not been compiling for me.

Within targetClassTester, I have this:

TEST_F(tester_base, exp) 
{
    myMap = myTargetClass.privateMap;
}

Meanwhile, in the header file for targetClass, I have the following in the private section:

FRIEND_TEST(tester_base, exp);

Finally, the following shows what the relevant parts of CMakeLists.txt would look like: (As a special note, targetClass.cpp contains a main() method and is normally created as its own executable. It's only for testing that I created the "targetClassForTesting" library. For unit testing, the main() method in targetClass.cpp is ignored.)

add_library(targetClassForTesting src/targetClass.cpp include/au_uav_ros/targetClass.h)

add_executable(targetClassTester include/myPackage/test/targetClassTester.h src/test/targetClassTester.cpp include/au_uav_ros/targetClass.h)

target_link_libraries(targetClassTester ${catkin_LIBRARIES} ${GTEST_LIBRARIES} targetClassForTesting)

add_rostest(test/targetClassTester.test)

There don't seem to be any other questions on the internet about FRIEND_TEST malfunctioning, making me think the issue is particular to ROS.

Let me know if you need any more information. Thank you.