/* -*- 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/. */
/* * * Date: 06 February 2003 * SUMMARY: Using |instanceof| to check if function is called as a constructor * * See http://bugzilla.mozilla.org/show_bug.cgi?id=192105 *
*/ //----------------------------------------------------------------------------- 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 = (thisinstanceof 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();
/* * 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();
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