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 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 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/. */

 /*

  *

  * Date:    15 July 2002

  * SUMMARY: Testing identifiers with double-byte names

  * See http://bugzilla.mozilla.org/show_bug.cgi?id=58274

  *

  * Here is a sample of the problem:

  *

  *    js> function f\u02B1 () {}

  *

  *    js> f\u02B1.toSource();

  *    function f¦() {}

  *

  *    js> f\u02B1.toSource().toSource();

  *    (new String("function f\xB1() {}"))

  *

  *

  * See how the high-byte information (the 02) has been lost?

  * The same thing was happening with the toString() method:

  *

  *    js> f\u02B1.toString();

  *

  *    function f¦() {

  *    }

  *

  *    js> f\u02B1.toString().toSource();

  *    (new String("\nfunction f\xB1() {\n}\n"))

  *

  */

 //-----------------------------------------------------------------------------

 var UBound = 0;

 var BUGNUMBER = 58274;

 var summary = 'Testing identifiers with double-byte names';

 var status = '';

 var statusitems = [];

 var actual = '';

 var actualvalues = [];

 var expect= '';

 var expectedvalues = [];

 /*

  * Define a function that uses double-byte identifiers in

  * "every possible way"

  *

  * Then recover each double-byte identifier via f.toString().

  * To make this easier, put a 'Z' token before every one.

  *

  * Our eval string will be:

  *

  * sEval = "function Z\u02b1(Z\u02b2, b) {

  *          try { Z\u02b3 : var Z\u02b4 = Z\u02b1; }

  *          catch (Z\u02b5) { for (var Z\u02b6 in Z\u02b5)

  *          {for (1; 1<0; Z\u02b7++) {new Array()[Z\u02b6] = 1;} };} }";

  *

  * It will be helpful to build this string in stages:

  */

 var s0 =  'function Z';

 var s1 =  '\u02b1(Z';

 var s2 =  '\u02b2, b) {try { Z';

 var s3 =  '\u02b3 : var Z';

 var s4 =  '\u02b4 = Z';

 var s5 =  '\u02b1; } catch (Z'

   var s6 =  '\u02b5) { for (var Z';

 var s7 =  '\u02b6 in Z';

 var s8 =  '\u02b5){for (1; 1<0; Z';

 var s9 =  '\u02b7++) {new Array()[Z';

 var s10 = '\u02b6] = 1;} };} }';

 /*

  * Concatenate these and eval() to create the function Z\u02b1

  */

 var sEval = s0 + s1 + s2 + s3 + s4 + s5 + s6 + s7 + s8 + s9 + s10;

 eval(sEval);

 /*

  * Recover all the double-byte identifiers via Z\u02b1.toString().

  * We'll recover the 1st one as arrID[1], the 2nd one as arrID[2],

  * and so on ...

  */

 var arrID = getIdentifiers(Z\u02b1);

 /*

  * Now check that we got back what we put in -

  */

 status = inSection(1);

 actual = arrID[1];

 expect = s1.charAt(0);

 addThis();

 status = inSection(2);

 actual = arrID[2];

 expect = s2.charAt(0);

 addThis();

 status = inSection(3);

 actual = arrID[3];

 expect = s3.charAt(0);

 addThis();

 status = inSection(4);

 actual = arrID[4];

 expect = s4.charAt(0);

 addThis();

 status = inSection(5);

 actual = arrID[5];

 expect = s5.charAt(0);

 addThis();

 status = inSection(6);

 actual = arrID[6];

 expect = s6.charAt(0);

 addThis();

 status = inSection(7);

 actual = arrID[7];

 expect = s7.charAt(0);

 addThis();

 status = inSection(8);

 actual = arrID[8];

 expect = s8.charAt(0);

 addThis();

 status = inSection(9);

 actual = arrID[9];

 expect = s9.charAt(0);

 addThis();

 status = inSection(10);

 actual = arrID[10];

 expect = s10.charAt(0);

 addThis();

 //-----------------------------------------------------------------------------

 test();

 //-----------------------------------------------------------------------------

 /*

  * Goal: recover the double-byte identifiers from f.toString()

  * by getting the very next character after each 'Z' token.

  *

  * The return value will be an array |arr| indexed such that

  * |arr[1]| is the 1st identifier, |arr[2]| the 2nd, and so on.

  *

  * Note, however, f.toString() is implementation-independent.

  * For example, it may begin with '\nfunction' instead of 'function'.

  *

  * Rhino uses a Unicode representation for f.toString(); whereas

  * SpiderMonkey uses an ASCII representation, putting escape sequences

  * for non-ASCII characters. For example, if a function is called f\u02B1,

  * then in Rhino the toString() method will present a 2-character Unicode

  * string for its name, whereas SpiderMonkey will present a 7-character

  * ASCII string for its name: the string literal 'f\u02B1'.

  *

  * So we force the lexer to condense the string before we use it.

  * This will give uniform results in Rhino and SpiderMonkey.

  */

 function getIdentifiers(f)

 {

   var str = condenseStr(f.toString());

   var arr = str.split('Z');

   /*

    * The identifiers are the 1st char of each split substring

    * EXCEPT the first one, which is just ('\n' +) 'function '.

    *

    * Thus note the 1st identifier will be stored in |arr[1]|,

    * the 2nd one in |arr[2]|, etc., making the indexing easy -

    */

   for (i in arr)

     arr[i] = arr[i].charAt(0);

   return arr;

 }

 /*

  * This function is the opposite of a functions like escape(), which take

  * Unicode characters and return escape sequences for them. Here, we force

  * the lexer to turn escape sequences back into single characters.

  *

  * Note we can't simply do |eval(str)|, since in practice |str| will be an

  * identifier somewhere in the program (e.g. a function name); thus |eval(str)|

  * would return the object that the identifier represents: not what we want.

  *

  * So we surround |str| lexicographically with quotes to force the lexer to

  * evaluate it as a string. Have to strip out any linefeeds first, however -

  */

 function condenseStr(str)

 {

   /*

    * You won't be able to do the next step if |str| has

    * any carriage returns or linefeeds in it. For example:

    *

    *  js> eval("'" + '\nHello' + "'");

    *  1: SyntaxError: unterminated string literal:

    *  1: '

    *  1: ^

    *

    * So replace them with the empty string -

    */

   str = str.replace(/[\r\n]/g, '')

     return eval("'" + str + "'")

     }

 function addThis()

 {

   statusitems[UBound] = status;

   actualvalues[UBound] = actual;

   expectedvalues[UBound] = expect;

   UBound++;

 }

 function test()

 {

   enterFunc('test');

   printBugNumber(BUGNUMBER);

   printStatus(summary);

   for (var i=0; i<UBound; i++)

   {

     reportCompare(expectedvalues[i], actualvalues[i], statusitems[i]);

   }

   exitFunc ('test');

 }