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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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/*
* Date: 2001-07-13
*
* SUMMARY: Applying Function.prototype.call to the Function object itself
*
*
* ECMA-262 15.3.4.4 Function.prototype.call (thisArg [,arg1 [,arg2,…] ] )
*
* When applied to the Function object itself, thisArg should be ignored.
* As explained by Waldemar (waldemar@netscape.com):
*
* Function.call(obj, "print(this)") is equivalent to invoking
* Function("print(this)") with this set to obj. Now, Function("print(this)")
* is equivalent to new Function("print(this)") (see 15.3.1.1), and the latter
* ignores the this value that you passed it and constructs a function
* (which we'll call F) which will print the value of the this that will be
* passed in when F will be invoked.
*
* With the last set of () you're invoking F(), which means you're calling it
* with no this value. When you don't provide a this value, it defaults to the
* global object.
*
*/
//-----------------------------------------------------------------------------
var UBound = 0;
var BUGNUMBER = '(none)';
var summary = 'Applying Function.prototype.call to the Function object itself';
var status = '';
var statusitems = [];
var actual = '';
var actualvalues = [];
var expect= '';
var expectedvalues = [];
var self = this; // capture a reference to the global object
var cnOBJECT_GLOBAL = self.toString();
var cnOBJECT_OBJECT = (new Object).toString();
var cnHello = 'Hello';
var cnRed = 'red';
var objTEST = {color:cnRed};
var f = new Function();
var g = new Function();
f = Function.call(self, 'return cnHello');
g = Function.call(objTEST, 'return cnHello');
status = 'Section A of test';
actual = f();
expect = cnHello;
captureThis();
status = 'Section B of test';
actual = g();
expect = cnHello;
captureThis();
f = Function.call(self, 'return this.toString()');
g = Function.call(objTEST, 'return this.toString()');
status = 'Section C of test';
actual = f();
expect = cnOBJECT_GLOBAL;
captureThis();
status = 'Section D of test';
actual = g();
expect = cnOBJECT_GLOBAL;
captureThis();
f = Function.call(self, 'return this.color');
g = Function.call(objTEST, 'return this.color');
status = 'Section E of test';
actual = f();
expect = undefined;
captureThis();
status = 'Section F of test';
actual = g();
expect = undefined;
captureThis();
//-----------------------------------------------------------------------------
test();
//-----------------------------------------------------------------------------
function captureThis()
{
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');
}
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