index.js

/*
 * Natural Sort algorithm for Javascript - Version 0.7 - Released under MIT license
 * Author: Jim Palmer (based on chunking idea from Dave Koelle)
 */

module.exports = function(a, b, options) {
  var re = /(^-?[0-9]+(\.?[0-9]*)[df]?e?[0-9]?$|^0x[0-9a-f]+$|[0-9]+)/gi,
    sre = /(^[ ]*|[ ]*$)/g,
    dre = /(^([\w ]+,?[\w ]+)?[\w ]+,?[\w ]+\d+:\d+(:\d+)?[\w ]?|^\d{1,4}[\/\-]\d{1,4}[\/\-]\d{1,4}|^\w+, \w+ \d+, \d{4})/,
    hre = /^0x[0-9a-f]+$/i,
    ore = /^0/,
    options = options || {},
    i = function(s) { return options.insensitive && (''+s).toLowerCase() || ''+s },
    // convert all to strings strip whitespace
    x = i(a).replace(sre, '') || '',
    y = i(b).replace(sre, '') || '',
    // chunk/tokenize
    xN = x.replace(re, '\0$1\0').replace(/\0$/,'').replace(/^\0/,'').split('\0'),
    yN = y.replace(re, '\0$1\0').replace(/\0$/,'').replace(/^\0/,'').split('\0'),
    // numeric, hex or date detection
    xD = parseInt(x.match(hre)) || (xN.length !== 1 && x.match(dre) && Date.parse(x)),
    yD = parseInt(y.match(hre)) || xD && y.match(dre) && Date.parse(y) || null,
    oFxNcL, oFyNcL,
    mult = options.desc ? -1 : 1;
  // first try and sort Hex codes or Dates
  if (yD)
    if ( xD < yD ) return -1 * mult;
    else if ( xD > yD ) return 1 * mult;
  // natural sorting through split numeric strings and default strings
  for(var cLoc=0, numS=Math.max(xN.length, yN.length); cLoc < numS; cLoc++) {
    // find floats not starting with '0', string or 0 if not defined (Clint Priest)
    oFxNcL = !(xN[cLoc] || '').match(ore) && parseFloat(xN[cLoc]) || xN[cLoc] || 0;
    oFyNcL = !(yN[cLoc] || '').match(ore) && parseFloat(yN[cLoc]) || yN[cLoc] || 0;
    // handle numeric vs string comparison - number < string - (Kyle Adams)
    if (isNaN(oFxNcL) !== isNaN(oFyNcL)) { return (isNaN(oFxNcL) ? 1 : -1) * mult; }
    // rely on string comparison if different types - i.e. '02' < 2 != '02' < '2'
    else if (typeof oFxNcL !== typeof oFyNcL) {
      oFxNcL += '';
      oFyNcL += '';
    }
    if (oFxNcL < oFyNcL) return -1 * mult;
    if (oFxNcL > oFyNcL) return 1 * mult;
  }
  return 0;
};

/*
var defaultSort = getSortFunction();

module.exports = function(a, b, options) {
  if (arguments.length == 1) {
    options = a;
    return getSortFunction(options);
  } else {
    return defaultSort(a,b);
  }
}
*/