code: function resolve( dir ) {
  	var udir = dir || configdir();
  	if ( udir === null ) {
  		debug( 'Unable to resolve user configuration directory.' );
  	} else {
  		udir = path.resolve( root, udir );
  		debug( 'User configuration directory: %s', udir );
  	}
  	return udir;
  }
docs: USER DIR // 
  FUNCTION: resolve( dir )
  Resolves a user configuration directory.
  
  @param {Void|String} dir - user configuration directory
  @returns {String|Null} resolved directory path or null