utils.js 1.98 KB
/**
 * Repeats a string.
 *
 * @param {String} char(s)
 * @param {Number} number of times
 * @return {String} repeated string
 */

exports.repeat = function (str, times){
  return Array(times + 1).join(str);
};

/**
 * Pads a string
 *
 * @api public
 */

exports.pad = function (str, len, pad, dir) {
  if (len + 1 >= str.length)
    switch (dir){
      case 'left':
        str = Array(len + 1 - str.length).join(pad) + str;
        break;

      case 'both':
        var right = Math.ceil((padlen = len - str.length) / 2);
        var left = padlen - right;
        str = Array(left + 1).join(pad) + str + Array(right + 1).join(pad);
        break;

      default:
        str = str + Array(len + 1 - str.length).join(pad);
    };

  return str;
};

/**
 * Truncates a string
 *
 * @api public
 */

exports.truncate = function (str, length, chr){
  chr = chr || '…';
  return str.length >= length ? str.substr(0, length - chr.length) + chr : str;
};

/**
 * Copies and merges options with defaults.
 *
 * @param {Object} defaults
 * @param {Object} supplied options
 * @return {Object} new (merged) object
 */

function options(defaults, opts) {
  for (var p in opts) {
    if (p === '__proto__' || p === 'constructor' || p === 'prototype') {
        continue;
    }
    if (opts[p] && opts[p].constructor && opts[p].constructor === Object) {
      defaults[p] = defaults[p] || {};
      options(defaults[p], opts[p]);
    } else {
      defaults[p] = opts[p];
    }
  }
  return defaults;
};
exports.options = options;

//
// For consideration of terminal "color" programs like colors.js,
// which can add ANSI escape color codes to strings,
// we destyle the ANSI color escape codes for padding calculations.
//
// see: http://en.wikipedia.org/wiki/ANSI_escape_code
//
exports.strlen = function(str){
  var code = /\u001b\[(?:\d*;){0,5}\d*m/g;
  var stripped = ("" + str).replace(code,'');
  var split = stripped.split("\n");
  return split.reduce(function (memo, s) { return (s.length > memo) ? s.length : memo }, 0);
}