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/* -*- 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
/*
*
* Date: 06 February 2003
* SUMMARY: Using |instanceof| to check if function is called as a constructor
*
*
*/
//-----------------------------------------------------------------------------
var UBound = 0;
var BUGNUMBER = 192105;
var summary = 'Using |instanceof| to check if f() is called as constructor';
var status = '';
var statusitems = [];
var actual = '';
var actualvalues = [];
var expect= '';
var expectedvalues = [];
/*
* This function is the heart of the test. It sets the result
* variable |actual|, which we will compare against |expect|.
*
* Note |actual| will be set to |true| or |false| according
* to whether or not this function is called as a constructor;
* i.e. whether it is called via the |new| keyword or not -
*/
function f()
{
actual = (this instanceof f);
}
/*
* Call f as a constructor from global scope
*/
status = inSection(1);
new f(); // sets |actual|
expect = true;
addThis();
/*
* Now, not as a constructor
*/
status = inSection(2);
f(); // sets |actual|
expect = false;
addThis();
/*
* Call f as a constructor from function scope
*/
function F()
{
new f();
}
status = inSection(3);
F(); // sets |actual|
expect = true;
addThis();
/*
* Now, not as a constructor
*/
function G()
{
f();
}
status = inSection(4);
G(); // sets |actual|
expect = false;
addThis();
/*
* Now make F() and G() methods of an object
*/
var obj = {F:F, G:G};
status = inSection(5);
obj.F(); // sets |actual|
expect = true;
addThis();
status = inSection(6);
obj.G(); // sets |actual|
expect = false;
addThis();
/*
* Now call F() and G() from yet other functions, and use eval()
*/
function A()
{
eval('F();');
}
status = inSection(7);
A(); // sets |actual|
expect = true;
addThis();
function B()
{
eval('G();');
}
status = inSection(8);
B(); // sets |actual|
expect = false;
addThis();
//-----------------------------------------------------------------------------
test();
//-----------------------------------------------------------------------------
function addThis()
{
statusitems[UBound] = status;
actualvalues[UBound] = actual;
expectedvalues[UBound] = expect;
UBound++;
}
function test()
{
printBugNumber(BUGNUMBER);
printStatus(summary);
for (var i=0; i<UBound; i++)
{
reportCompare(expectedvalues[i], actualvalues[i], statusitems[i]);
}
}