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      1 /* The contents of this file are subject to the Netscape Public
      2  * License Version 1.1 (the "License"); you may not use this file
      3  * except in compliance with the License. You may obtain a copy of
      4  * the License at http://www.mozilla.org/NPL/
      5  *
      6  * Software distributed under the License is distributed on an "AS
      7  * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
      8  * implied. See the License for the specific language governing
      9  * rights and limitations under the License.
     10  *
     11  * The Original Code is Mozilla Communicator client code, released March
     12  * 31, 1998.
     13  *
     14  * The Initial Developer of the Original Code is Netscape Communications
     15  * Corporation. Portions created by Netscape are
     16  * Copyright (C) 1998 Netscape Communications Corporation. All
     17  * Rights Reserved.
     18  *
     19  * Contributor(s):
     20  *
     21  */
     22 /**
     23     File Name:          15.5.4.7-3.js
     24     ECMA Section:       15.5.4.7 String.prototype.lastIndexOf( searchString, pos)
     25     Description:
     26 
     27     If the given searchString appears as a substring of the result of
     28     converting this object to a string, at one or more positions that are
     29     at or to the left of the specified position, then the index of the
     30     rightmost such position is returned; otherwise -1 is returned. If position
     31     is undefined or not supplied, the length of this string value is assumed,
     32     so as to search all of the string.
     33 
     34     When the lastIndexOf method is called with two arguments searchString and
     35     position, the following steps are taken:
     36 
     37    1.Call ToString, giving it the this value as its argument.
     38    2.Call ToString(searchString).
     39    3.Call ToNumber(position). (If position is undefined or not supplied, this step produces the value NaN).
     40    4.If Result(3) is NaN, use +; otherwise, call ToInteger(Result(3)).
     41    5.Compute the number of characters in Result(1).
     42    6.Compute min(max(Result(4), 0), Result(5)).
     43    7.Compute the number of characters in the string that is Result(2).
     44    8.Compute the largest possible integer k not larger than Result(6) such that k+Result(7) is not greater
     45       than Result(5), and for all nonnegative integers j less than Result(7), the character at position k+j of
     46       Result(1) is the same as the character at position j of Result(2); but if there is no such integer k, then
     47       compute the value -1.
     48 
     49    1.Return Result(8).
     50 
     51     Note that the lastIndexOf function is intentionally generic; it does not require that its this value be a
     52     String object. Therefore it can be transferred to other kinds of objects for use as a method.
     53 
     54     Author:             christine (at) netscape.com
     55     Date:               2 october 1997
     56 */
     57     var SECTION = "15.5.4.7-3";
     58     var VERSION = "ECMA_2";
     59     startTest();
     60     var TITLE   = "String.protoype.lastIndexOf";
     61 
     62     writeHeaderToLog( SECTION + " "+ TITLE);
     63 
     64     var testcases = getTestCases();
     65     test();
     66 
     67 
     68 function getTestCases() {
     69     var array = new Array();
     70     var item = 0;
     71 
     72     array[item++] = new TestCase(   SECTION,
     73                                     "var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 0 )",
     74                                     -1,
     75                                     eval("var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 0 )") );
     76 
     77     array[item++] = new TestCase(   SECTION,
     78                                     "var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 1 )",
     79                                     1,
     80                                     eval("var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 1 )") );
     81 
     82     array[item++] = new TestCase(   SECTION,
     83                                     "var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 2 )",
     84                                     1,
     85                                     eval("var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 2 )") );
     86 
     87     array[item++] = new TestCase(   SECTION,
     88                                     "var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 10 )",
     89                                     1,
     90                                     eval("var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 10 )") );
     91 
     92     array[item++] = new TestCase(   SECTION,
     93                                     "var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r' )",
     94                                     1,
     95                                     eval("var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r' )") );
     96 
     97     return array;
     98 }
     99 
    100 function test() {
    101     for ( tc = 0; tc < testcases.length; tc++ ) {
    102 
    103         testcases[tc].passed = writeTestCaseResult(
    104                     testcases[tc].expect,
    105                     testcases[tc].actual,
    106                     testcases[tc].description +" = "+ testcases[tc].actual );
    107 
    108         testcases[tc].reason += ( testcases[tc].passed ) ? "" : "wrong value "
    109     }
    110     stopTest();
    111 
    112     return ( testcases );
    113 }
    114 
    115 function LastIndexOf( string, search, position ) {
    116     string = String( string );
    117     search = String( search );
    118 
    119     position = Number( position )
    120 
    121     if ( isNaN( position ) ) {
    122         position = Infinity;
    123     } else {
    124         position = ToInteger( position );
    125     }
    126 
    127     result5= string.length;
    128     result6 = Math.min(Math.max(position, 0), result5);
    129     result7 = search.length;
    130 
    131     if (result7 == 0) {
    132         return Math.min(position, result5);
    133     }
    134 
    135     result8 = -1;
    136 
    137     for ( k = 0; k <= result6; k++ ) {
    138         if ( k+ result7 > result5 ) {
    139             break;
    140         }
    141         for ( j = 0; j < result7; j++ ) {
    142             if ( string.charAt(k+j) != search.charAt(j) ){
    143                 break;
    144             }   else  {
    145                 if ( j == result7 -1 ) {
    146                     result8 = k;
    147                 }
    148             }
    149         }
    150     }
    151 
    152     return result8;
    153 }
    154 function ToInteger( n ) {
    155     n = Number( n );
    156     if ( isNaN(n) ) {
    157         return 0;
    158     }
    159     if ( Math.abs(n) == 0 || Math.abs(n) == Infinity ) {
    160         return n;
    161     }
    162 
    163     var sign = ( n < 0 ) ? -1 : 1;
    164 
    165     return ( sign * Math.floor(Math.abs(n)) );
    166 }