gn analyze output:
{
  "compile_targets": [],
  "status": "No dependency",
  "test_targets": []
}
gn analyze input:
{
  "files": [
    "//libcxx/include/CMakeLists.txt",
    "//libcxx/include/__fwd/optional.h",
    "//libcxx/include/__optional/common.h",
    "//libcxx/include/__optional/comparison.h",
    "//libcxx/include/__optional/hash.h",
    "//libcxx/include/__optional/make_optional.h",
    "//libcxx/include/__optional/nullopt_t.h",
    "//libcxx/include/__optional/optional.h",
    "//libcxx/include/__optional/optional_ref.h",
    "//libcxx/include/__optional/swap.h",
    "//libcxx/include/module.modulemap.in",
    "//libcxx/include/optional",
    "//libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.creation/make_ostream_joiner.pass.cpp",
    "//libcxx/test/std/experimental/iterator/ostream.joiner/ostream.joiner.ops/ostream_joiner.op.assign.pass.cpp",
    "//libcxx/test/std/utilities/optional/optional.bad_optional_access/derive.pass.cpp",
    "//libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/ctor.verify.cpp",
    "//libcxx/test/std/utilities/optional/optional.object/optional.object.ctor/deduct.verify.cpp",
    "//libcxx/test/std/utilities/optional/optional.object/optional_requires_destructible_object.verify.cpp",
    "//llvm/utils/gn/secondary/libcxx/include/BUILD.gn"
  ],
  "test_targets": [
    "//clang-tools-extra/clangd/test:check-clangd",
    "//clang-tools-extra/test:check-clang-tools",
    "//clang/test:check-clang",
    "//compiler-rt/test/hwasan:check-hwasan",
    "//lld/test:check-lld",
    "//llvm/test:check-llvm"
  ],
  "additional_compile_targets": []
}
running all tests due to change to blacklisted file