tests/mozilla/ecma/Statements/12.10-1.js

   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:          12.10-1.js
  24     ECMA Section:       12.10 The with statement
  25     Description:
  26     WithStatement :
  27     with ( Expression ) Statement
  28
  29     The with statement adds a computed object to the front of the scope chain
  30     of the current execution context, then executes a statement with this
  31     augmented scope chain, then restores the scope chain.
  32
  33     Semantics
  34
  35     The production WithStatement : with ( Expression ) Statement is evaluated
  36     as follows:
  37     1.  Evaluate Expression.
  38     2.  Call GetValue(Result(1)).
  39     3.  Call ToObject(Result(2)).
  40     4.  Add Result(3) to the front of the scope chain.
  41     5.  Evaluate Statement using the augmented scope chain from step 4.
  42     6.  Remove Result(3) from the front of the scope chain.
  43     7.  Return Result(5).
  44
  45     Discussion
  46     Note that no matter how control leaves the embedded Statement, whether
  47     normally or by some form of abrupt completion, the scope chain is always
  48     restored to its former state.
  49
  50     Author:             christine@netscape.com
  51     Date:               12 november 1997
  52 */
  53
  54     var SECTION = "12.10-1";
  55     var VERSION = "ECMA_1";
  56     startTest();
  57     var TITLE   = "The with statment";
  58
  59     writeHeaderToLog( SECTION + " "+ TITLE);
  60
  61     var testcases = getTestCases();
  62
  63     test();
  64
  65 function test() {
  66     for ( tc=0; tc < testcases.length; tc++ ) {
  67         testcases[tc].passed = writeTestCaseResult(
  68                             testcases[tc].expect,
  69                             testcases[tc].actual,
  70                             testcases[tc].description +" = "+
  71                             testcases[tc].actual );
  72
  73         testcases[tc].reason += ( testcases[tc].passed ) ? "" : "wrong value ";
  74     }
  75     stopTest();
  76     return ( testcases );
  77 }
  78 function getTestCases() {
  79     var array = new Array();
  80     var item = 0;
  81
  82     // although the scope chain changes, the this value is immutable for a given
  83     // execution context.
  84
  85     array[item++] = new TestCase( SECTION,
  86                                 "with( new Number() ) { this +'' }",
  87                                 "[object global]",
  88                                 eval("with( new Number() ) { this +'' }") );
  89
  90     // the object's functions and properties should override those of the
  91     // global object.
  92
  93     array[item++] = new TestCase(
  94                         SECTION,
  95                         "var MYOB = new WithObject(true); with (MYOB) { parseInt() }",
  96                         true,
  97                         eval("var MYOB = new WithObject(true); with (MYOB) { parseInt() }") );
  98
  99     array[item++] = new TestCase(
 100                         SECTION,
 101                         "var MYOB = new WithObject(false); with (MYOB) { NaN }",
 102                         false,
 103                         eval("var MYOB = new WithObject(false); with (MYOB) { NaN }") );
 104
 105     array[item++] = new TestCase(
 106                         SECTION,
 107                         "var MYOB = new WithObject(NaN); with (MYOB) { Infinity }",
 108                         Number.NaN,
 109                         eval("var MYOB = new WithObject(NaN); with (MYOB) { Infinity }") );
 110
 111     array[item++] = new TestCase(
 112                         SECTION,
 113                         "var MYOB = new WithObject(false); with (MYOB) { }; Infinity",
 114                         Number.POSITIVE_INFINITY,
 115                         eval("var MYOB = new WithObject(false); with (MYOB) { }; Infinity") );
 116
 117
 118     array[item++] = new TestCase(
 119                         SECTION,
 120                         "var MYOB = new WithObject(0); with (MYOB) { delete Infinity; Infinity }",
 121                         Number.POSITIVE_INFINITY,
 122                         eval("var MYOB = new WithObject(0); with (MYOB) { delete Infinity; Infinity }") );
 123
 124     // let us leave the with block via a break.
 125
 126     array[item++] = new TestCase(
 127                         SECTION,
 128                         "var MYOB = new WithObject(0); while (true) { with (MYOB) { Infinity; break; } } Infinity",
 129                         Number.POSITIVE_INFINITY,
 130                         eval("var MYOB = new WithObject(0); while (true) { with (MYOB) { Infinity; break; } } Infinity") );
 131
 132     return ( array );
 133 }
 134 function WithObject( value ) {
 135     this.prop1 = 1;
 136     this.prop2 = new Boolean(true);
 137     this.prop3 = "a string";
 138     this.value = value;
 139
 140     // now we will override global functions
 141
 142     this.parseInt = new Function( "return this.value" );
 143     this.NaN = value;
 144     this.Infinity = value;
 145     this.unescape = new Function( "return this.value" );
 146     this.escape   = new Function( "return this.value" );
 147     this.eval     = new Function( "return this.value" );
 148     this.parseFloat = new Function( "return this.value" );
 149     this.isNaN      = new Function( "return this.value" );
 150     this.isFinite   = new Function( "return this.value" );
 151 }