message: [vcpkg] Fix use of features in undocumented build command
diff: @@ -52,22 +52,20 @@ namespace vcpkg::Build::Command
  Checks::exit_fail(VCPKG_LINE_INFO);
  }
  - for (const std::string& str : full_spec.features)
  - {
  - System::println("%s \n", str);
  - }
  const auto& scf = source_control_file.value_or_exit(VCPKG_LINE_INFO);
  Checks::check_exit(VCPKG_LINE_INFO,
  spec.name() == scf->core_paragraph->name,
  - "The Name: field inside the CONTROL does not match the port directory: '%s' != '%s'",
  + "The Source field inside the CONTROL file does not match the port directory: '%s' != '%s'",
  scf->core_paragraph->name,
  spec.name());
  const StatusParagraphs status_db = database_load_check(paths);
  const Build::BuildPackageOptions build_package_options{Build::UseHeadVersion::NO, Build::AllowDownloads::YES};
  + const std::unordered_set<std::string> features_as_set(full_spec.features.begin(), full_spec.features.end());
  +
  const Build::BuildPackageConfig build_config{
  - *scf->core_paragraph, spec.triplet(), paths.port_dir(spec), build_package_options};
  + *scf, spec.triplet(), fs::path{port_dir}, build_package_options, features_as_set};
  const auto build_timer = Chrono::ElapsedTime::create_started();
  const auto result = Build::build_package(paths, build_config, status_db);
  @@ -107,6 +105,11 @@ namespace vcpkg::Build::Command
  const std::string command_argument = args.command_arguments.at(0);
  const FullPackageSpec spec = Input::check_and_get_full_package_spec(command_argument, default_triplet, EXAMPLE);
  Input::check_triplet(spec.package_spec.triplet(), paths);
  + if (!spec.features.empty() && !GlobalState::feature_packages)
  + {
  + Checks::exit_with_message(
  + VCPKG_LINE_INFO, "Feature packages are experimentally available under the --featurepackages flag.");
  + }
  const ParsedArguments options = args.check_and_get_optional_command_arguments({OPTION_CHECKS_ONLY}, {});
  perform_and_exit(spec, paths.port_dir(spec.package_spec), options, paths);
  }
  