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/* -*- tab-width: 2; indent-tabs-mode: nil; js-indent-level: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/**
File Name: 15.5.4.7-3.js
ECMA Section: 15.5.4.7 String.prototype.lastIndexOf( searchString, pos)
Description:
If the given searchString appears as a substring of the result of
converting this object to a string, at one or more positions that are
at or to the left of the specified position, then the index of the
rightmost such position is returned; otherwise -1 is returned. If position
is undefined or not supplied, the length of this string value is assumed,
so as to search all of the string.
When the lastIndexOf method is called with two arguments searchString and
position, the following steps are taken:
1.Call ToString, giving it the this value as its argument.
2.Call ToString(searchString).
3.Call ToNumber(position). (If position is undefined or not supplied, this step produces the value NaN).
4.If Result(3) is NaN, use +; otherwise, call ToInteger(Result(3)).
5.Compute the number of characters in Result(1).
6.Compute min(max(Result(4), 0), Result(5)).
7.Compute the number of characters in the string that is Result(2).
8.Compute the largest possible integer k not larger than Result(6) such that k+Result(7) is not greater
than Result(5), and for all nonnegative integers j less than Result(7), the character at position k+j of
Result(1) is the same as the character at position j of Result(2); but if there is no such integer k, then
compute the value -1.
1.Return Result(8).
Note that the lastIndexOf function is intentionally generic; it does not require that its this value be a
String object. Therefore it can be transferred to other kinds of objects for use as a method.
Author: christine@netscape.com
Date: 2 october 1997
*/
var SECTION = "15.5.4.7-3";
var VERSION = "ECMA_2";
startTest();
var TITLE = "String.protoype.lastIndexOf";
writeHeaderToLog( SECTION + " "+ TITLE);
new TestCase( SECTION,
"var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 0 )",
-1,
eval("var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 0 )") );
new TestCase( SECTION,
"var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 1 )",
1,
eval("var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 1 )") );
new TestCase( SECTION,
"var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 2 )",
1,
eval("var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 2 )") );
new TestCase( SECTION,
"var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 10 )",
1,
eval("var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r', 10 )") );
new TestCase( SECTION,
"var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r' )",
1,
eval("var b = true; b.__proto__.lastIndexOf = String.prototype.lastIndexOf; b.lastIndexOf('r' )") );
test();
function LastIndexOf( string, search, position ) {
string = String( string );
search = String( search );
position = Number( position )
if ( isNaN( position ) ) {
position = Infinity;
} else {
position = ToInteger( position );
}
result5= string.length;
result6 = Math.min(Math.max(position, 0), result5);
result7 = search.length;
if (result7 == 0) {
return Math.min(position, result5);
}
result8 = -1;
for ( k = 0; k <= result6; k++ ) {
if ( k+ result7 > result5 ) {
break;
}
for ( j = 0; j < result7; j++ ) {
if ( string.charAt(k+j) != search.charAt(j) ){
break;
} else {
if ( j == result7 -1 ) {
result8 = k;
}
}
}
}
return result8;
}
function ToInteger( n ) {
n = Number( n );
if ( isNaN(n) ) {
return 0;
}
if ( Math.abs(n) == 0 || Math.abs(n) == Infinity ) {
return n;
}
var sign = ( n < 0 ) ? -1 : 1;
return ( sign * Math.floor(Math.abs(n)) );
}
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