| /* -*- 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)) ); |
| } |