tests/mozilla/ecma_3/Function/arguments-001.js

   1 /*
   2 * The contents of this file are subject to the Netscape Public
   3 * License Version 1.1 (the "License"); you may not use this file
   4 * except in compliance with the License. You may obtain a copy of
   5 * the License at http://www.mozilla.org/NPL/
   6 *
   7 * Software distributed under the License is distributed on an "AS
   8 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
   9 * implied. See the License for the specific language governing
  10 * rights and limitations under the License.
  11 *
  12 * The Original Code is mozilla.org code.
  13 *
  14 * The Initial Developer of the Original Code is Netscape
  15 * Communications Corporation.  Portions created by Netscape are
  16 * Copyright (C) 1998 Netscape Communications Corporation. All
  17 * Rights Reserved.
  18 *
  19 * Contributor(s): brendan@mozilla.org, pschwartau@netscape.com
  20 * Date: 07 May 2001
  21 *
  22 * SUMMARY:  Testing the arguments object
  23 *
  24 * See http://bugzilla.mozilla.org/show_bug.cgi?id=72884
  25 */
  26 //-------------------------------------------------------------------------------------------------
  27 var UBound = 0;
  28 var bug = 72884;
  29 var summary = 'Testing the arguments object';
  30 var status = '';
  31 var statusitems = [ ];
  32 var actual = '';
  33 var actualvalues = [ ];
  34 var expect= '';
  35 var expectedvalues = [ ];
  36 var a = '';
  37
  38
  39 status = inSection(1);
  40 function f()
  41 {
  42   delete arguments.length;
  43   return arguments;
  44 }
  45
  46 a = f();
  47 actual = a instanceof Object;
  48 expect = true;
  49 addThis();
  50
  51 actual = a instanceof Array;
  52 expect = false;
  53 addThis();
  54
  55 actual = a.length;
  56 expect = undefined;
  57 addThis();
  58
  59
  60
  61 status = inSection(2);
  62 a = f(1,2,3);
  63 actual = a instanceof Object;
  64 expect = true;
  65 addThis();
  66
  67 actual = a instanceof Array;
  68 expect = false;
  69 addThis();
  70
  71 actual = a.length;
  72 expect = undefined;
  73 addThis();
  74
  75 actual = a[0];
  76 expect = 1;
  77 addThis();
  78
  79 actual = a[1];
  80 expect = 2;
  81 addThis();
  82
  83 actual = a[2];
  84 expect = 3;
  85 addThis();
  86
  87
  88
  89 status = inSection(3);
  90 /*
  91  * Brendan:
  92  *
  93  * Note that only callee and length can be overridden, so deleting an indexed
  94  * property and asking for it again causes it to be recreated by args_resolve:
  95  *
  96  * function g(){delete arguments[0]; return arguments[0]}
  97  * g(42)     // should this print 42?
  98  *
  99  * I'm not positive this violates ECMA, which allows in chapter 16 for extensions
 100  * including properties (does it allow for magically reappearing properties?).  The
 101  * delete operator successfully deletes arguments[0] and results in true, but that
 102  * is not distinguishable from the case where arguments[0] was delegated to
 103  * Arguments.prototype[0], which was how the bad old code worked.
 104  *
 105  * I'll ponder this last detail...
 106  *
 107  * UPDATE: Per ECMA-262, delete on an arguments[i] should succeed
 108  * and remove that property from the arguments object, leaving any get
 109  * of it after the delete to evaluate to undefined.
 110  */
 111 function g()
 112 {
 113   delete arguments[0];
 114   return arguments[0];
 115 }
 116 actual = g(42);
 117 expect = undefined;  // not 42...
 118 addThis();
 119
 120
 121
 122 //-------------------------------------------------------------------------------------------------
 123 test();
 124 //-------------------------------------------------------------------------------------------------
 125
 126
 127 function addThis()
 128 {
 129   statusitems[UBound] = status;
 130   actualvalues[UBound] = actual;
 131   expectedvalues[UBound] = expect;
 132   UBound++;
 133 }
 134
 135
 136 function test()
 137 {
 138   enterFunc ('test');
 139   printBugNumber (bug);
 140   printStatus (summary);
 141
 142   for (var i = 0; i < UBound; i++)
 143   {
 144     reportCompare(expectedvalues[i], actualvalues[i], statusitems[i]);
 145   }
 146
 147   exitFunc ('test');
 148 }