version_compare.js

(function(exports){
  /**
   * Compares two software version numbers (e.g. "1.7.1" or "1.2b").
   *
   * This function was born in http://stackoverflow.com/a/6832721.
   *
   * @param {string} v1 The first version to be compared.
   * @param {string} v2 The second version to be compared.
   * @param {object} [options] Optional flags that affect comparison behavior:
   * <ul>
   *     <li>
   *         <tt>lexicographical: true</tt> compares each part of the version strings lexicographically instead of
   *         naturally; this allows suffixes such as "b" or "dev" but will cause "1.10" to be considered smaller than
   *         "1.2".
   *     </li>
   *     <li>
   *         <tt>zeroExtend: true</tt> changes the result if one version string has less parts than the other. In
   *         this case the shorter string will be padded with "zero" parts instead of being considered smaller.
   *     </li>
   * </ul>
   * @returns {number|NaN}
   * <ul>
   *    <li>0 if the versions are equal</li>
   *    <li>a negative integer iff v1 < v2</li>
   *    <li>a positive integer iff v1 > v2</li>
   *    <li>NaN if either version string is in the wrong format</li>
   * </ul>
   *
   * @copyright by Jon Papaioannou (["john", "papaioannou"].join(".") + "@gmail.com")
   * @license This function is in the public domain. Do what you want with it, no strings attached.
   */
  function compare(v1, v2, options) {
      //remove anything after - 1.1.2-3-a4agbr-dirty
      function cropDash(s){
        var idx = s.indexOf('-');
        if(idx !== -1) {
          s = s.substring(0, idx);
        }
        return s;
      }

      v1 = cropDash(v1);
      v2 = cropDash(v2);
      var lexicographical = options && options.lexicographical,
          zeroExtend = options && options.zeroExtend,
          v1parts = v1.split('.'),
          v2parts = v2.split('.');


      


      function isValidPart(x) {
          return (lexicographical ? /^\d+[A-Za-z]*$/ : /^\d+$/).test(x);
      }

      if (!v1parts.every(isValidPart) || !v2parts.every(isValidPart)) {
          return NaN;
      }

      if (zeroExtend) {
          while (v1parts.length < v2parts.length) v1parts.push("0");
          while (v2parts.length < v1parts.length) v2parts.push("0");
      }

      if (!lexicographical) {
          v1parts = v1parts.map(Number);
          v2parts = v2parts.map(Number);
      }

      for (var i = 0; i < v1parts.length; ++i) {
          if (v2parts.length == i) {
              return 1;
          }

          if (v1parts[i] == v2parts[i]) {
              continue;
          }
          else if (v1parts[i] > v2parts[i]) {
              return 1;
          }
          else {
              return -1;
          }
      }

      if (v1parts.length != v2parts.length) {
          return -1;
      }

      return 0;
  }

  function matches(v1, v2, options){
    return compare(v1, v2, options) === 0;
  }

  function gt(v1, v2, options){
    return compare(v1, v2, options) > 0;
  }
  function gte(v1, v2, options){
    return compare(v1, v2, options) >= 0;
  }
  function lt(v1, v2, options){
    return compare(v1, v2, options) < 0;
  }
  function lte(v1, v2, options){
    return compare(v1, v2, options) <= 0;
  }

  exports.compare = compare;
  exports.matches = matches;
  exports.gt = gt;
  exports.gte = gte;
  exports.lt = lt;
  exports.lte = lte;

  String.prototype.endsWith = function(suffix) {
      return this.indexOf(suffix, this.length - suffix.length) !== -1;
  };
})(typeof exports === 'undefined'? this.VersionCompare = {}: exports);