private @NotNull Collection<@NlsSafe String> getPropertyNames(File[] files) {
    final Collection<String> names = new TreeSet<>();
    if (files.length == 1) {
      File file = files[0];
      try {
        PropertyConsumer handler = new PropertyConsumer() {
          @Override
          public void handleProperty(File path, PropertyData property) {
            names.add(property.getName());
          }
        };

        PropertyClient client = myVCS.getFactory(file).createPropertyClient();
        client.list(Target.on(file, Revision.WORKING), Revision.WORKING, Depth.EMPTY, handler);
      }
      catch (SvnBindException e) {
        LOG.info(e);
      }
    }

    addAll(names, SVN_EOL_STYLE, SVN_KEYWORDS, SVN_NEEDS_LOCK, SVN_MIME_TYPE, SVN_EXECUTABLE, SVN_IGNORE, SVN_EXTERNALS);
    return names;
  }
private @NotNull Collection<@NlsSafe String> getPropertyNames(File[] files)