sebastian-software/core

/*
==================================================================================================
  Core - JavaScript Foundation
  Copyright 2013-2014 Sebastian Werner
--------------------------------------------------------------------------------------------------
  Based on ES5-Shim
  https://github.com/kriskowal/es5-shim
  Copyright 2009-2013 by contributors, MIT License
==================================================================================================
*/

"use strict";

(function()
{
  var boxedString = Object("a");
  var splitString = boxedString[0] != "a" || !(0 in boxedString);

  // ES5 9.9
  // http://es5.github.com/#x9.9
  var toObject = function (o)
  {
    if (o == null) { // this matches both null and undefined
      throw new TypeError("can't convert "+o+" to object");
    }

    return Object(o);
  };

  var toInteger = function(n)
  {
    n = +n;
    if (n !== n) { // isNaN
      n = 0;
    } else if (n !== 0 && n !== (1/0) && n !== -(1/0)) {
      n = (n > 0 || -1) * Math.floor(Math.abs(n));
    }

    return n;
  };

  /**
   * This fixes the missing support of Array.indexOf/Array.lastIndexOf in IE < 9.
   */
  core.Main.addMembers("Array",
  {
    /**
     * Returns the first index at which a given element can be found in the array, or -1 if it is not present.
     *
     * - ES5 15.4.4.14
     * - http://es5.github.com/#x15.4.4.14
     * - https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/indexOf
     */
    indexOf : function(sought /*, fromIndex */ )
    {
      var self = splitString && core.Main.isTypeOf(this) == "String" ? this.split("") : toObject(this);
      var length = self.length >>> 0;

      if (!length) {
        return -1;
      }

      var i = 0;
      if (arguments.length > 1) {
        i = toInteger(arguments[1]);
      }

      // handle negative indices
      i = i >= 0 ? i : Math.max(0, length + i);
      for (; i < length; i++) {
        if (i in self && self[i] === sought) {
          return i;
        }
      }
      return -1;
    },


    /**
     * Returns the last index at which a given element can be found in the array, or -1 if
     * it is not present. The array is searched backwards, starting at fromIndex.
     *
     * - ES5 15.4.4.15
     * - http://es5.github.com/#x15.4.4.15
     * - https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/lastIndexOf
     */
    lastIndexOf : function(sought /*, fromIndex */)
    {
      var self = splitString && core.Main.isTypeOf(this) == "String" ? this.split("") : toObject(this);
      var length = self.length >>> 0;

      if (!length) {
        return -1;
      }

      var i = length - 1;
      if (arguments.length > 1) {
        i = Math.min(i, toInteger(arguments[1]));
      }

      // handle negative indices
      i = i >= 0 ? i : length - Math.abs(i);
      for (; i >= 0; i--)
      {
        if (i in self && sought === self[i]) {
          return i;
        }
      }

      return -1;
    }
  });
})();