gn analyze output:
{
  "compile_targets": [],
  "status": "No dependency",
  "test_targets": []
}
gn analyze input:
{
  "files": [
    "//libcxx/docs/TestingLibcxx.rst",
    "//libcxx/test/std/input.output/iostream.format/print.fun/includes.compile.pass.cpp",
    "//libcxx/test/std/input.output/iostream.format/print.fun/no_file_description.pass.cpp",
    "//libcxx/test/std/localization/locale.stdcvt/depr.verify.cpp",
    "//libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.buffer/depr.verify.cpp",
    "//libcxx/test/std/localization/locales/locale.convenience/conversions/conversions.string/depr.verify.cpp",
    "//libcxx/test/std/strings/basic.string/string.capacity/reserve.deprecated_in_cxx20.verify.cpp",
    "//libcxx/utils/libcxx/test/params.py"
  ],
  "test_targets": [
    "//clang-tools-extra/clangd/test:check-clangd",
    "//clang-tools-extra/test:check-clang-tools",
    "//clang/test:check-clang",
    "//lld/test:check-lld",
    "//llvm/test:check-llvm"
  ],
  "additional_compile_targets": []
}