Tests/RunCMake/XcodeProject/XcodeDependOnZeroCheck.cmake - third_party/github.com/Kitware/CMake - Git at Google

 set(CMAKE_XCODE_GENERATE_TOP_LEVEL_PROJECT_ONLY TRUE)
 project(XcodeDependOnZeroCheck CXX)
 add_subdirectory(zerocheck)
 add_library(parentdirlib foo.cpp)
	set(CMAKE_XCODE_GENERATE_TOP_LEVEL_PROJECT_ONLY TRUE)
	project(XcodeDependOnZeroCheck CXX)
	add_subdirectory(zerocheck)
	add_library(parentdirlib foo.cpp)