Tests/RunCMake/CXXModules/examples/unity-build/unity2.cxx - third_party/github.com/Kitware/CMake - Git at Google

 #include "unity.h"

 #ifndef DETECT_UNITY
 #  error "Should have detected a unity build"
 #endif

 int unity2()
 {
   return 0;
 }
	#include "unity.h"

	#ifndef DETECT_UNITY
	# error "Should have detected a unity build"
	#endif

	int unity2()
	{
	return 0;
	}