separate_arguments (out UNIX_COMMAND PROGRAM "xx a b c")
if (out)
  message (SEND_ERROR "unexpected result with nonexistent program")
endif()

set (TEST_EXE_DIR "${CMAKE_CURRENT_BINARY_DIR}/TestExe")
file(MAKE_DIRECTORY "${TEST_EXE_DIR}")
file(COPY "${CMAKE_COMMAND}" DESTINATION "${TEST_EXE_DIR}")
cmake_path (GET CMAKE_COMMAND FILENAME cmake_exe)

set (ENV{PATH} "${TEST_EXE_DIR}")


separate_arguments (out UNIX_COMMAND PROGRAM "${cmake_exe}")
list (LENGTH out length)
if (length EQUAL 0)
  message(FATAL_ERROR "existent program not found")
endif()
if (NOT length EQUAL 2)
  message(FATAL_ERROR "unexpected arguments")
endif()
list(GET out 0 cmake)
list(GET out 1 args)
if (NOT cmake STREQUAL "${TEST_EXE_DIR}/${cmake_exe}")
  message (SEND_ERROR "bad path for program: '${cmake}' instead of '${TEST_EXE_DIR}/${cmake_exe}'")
endif()
if (NOT args STREQUAL "")
  message (SEND_ERROR "bad value for args: '${args}' instead of ''")
endif()


separate_arguments (out UNIX_COMMAND PROGRAM "${cmake_exe} a b c")
list (LENGTH out length)
if (length EQUAL 0)
  message(FATAL_ERROR "existent program not found")
endif()
if (NOT length EQUAL 2)
  message(FATAL_ERROR "unexpected arguments")
endif()
list(GET out 0 cmake)
list(GET out 1 args)
if (NOT cmake STREQUAL "${TEST_EXE_DIR}/${cmake_exe}")
  message (SEND_ERROR "bad path for program: '${cmake}' instead of '${TEST_EXE_DIR}/${cmake_exe}'")
endif()
if (NOT args STREQUAL " a b c")
  message (SEND_ERROR "bad value for args: '${args}' instead of ' a b c'")
endif()