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 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 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: 28 May 2001

  *

  * SUMMARY:  Functions are scoped statically, not dynamically

  *

  * See ECMA Section 10.1.4 Scope Chain and Identifier Resolution

  * (This section defines the scope chain of an execution context)

  *

  * See ECMA Section 12.10 The with Statement

  *

  * See ECMA Section 13 Function Definition

  * (This section defines the scope chain of a function object as that

  *  of the running execution context when the function was declared)

  */

 //-----------------------------------------------------------------------------

 var UBound = 0;

 var BUGNUMBER = '(none)';

 var summary = 'Testing that functions are scoped statically, not dynamically';

 var self = this;  // capture a reference to the global object

 var status = '';

 var statusitems = [ ];

 var actual = '';

 var actualvalues = [ ];

 var expect= '';

 var expectedvalues = [ ];

 /*

  * In this section the expected value is 1, not 2.

  *

  * Why? f captures its scope chain from when it's declared, and imposes that chain

  * when it's executed. In other words, f's scope chain is from when it was compiled.

  * Since f is a top-level function, this is the global object only. Hence 'a' resolves to 1.

  */

 status = 'Section A of test';

 var a = 1;

 function f()

 {

   return a;

 }

 var obj = {a:2};

 with (obj)

 {

   actual = f();

 }

 expect = 1;

 addThis();

 /*

  * In this section the expected value is 2, not 1. That is because here

  * f's associated scope chain now includes 'obj' before the global object.

  */

 status = 'Section B of test';

 var a = 1;

 var obj = {a:2};

 with (obj)

 {

   function f()

   {

     return a;

   }

   actual = f();

 }

 expect = 2;

 addThis();

 /*

  * Like Section B , except that we call f outside the with block.

  * By the principles explained above, we still expect 2 -

  */

 status = 'Section C of test';

 var a = 1;

 var obj = {a:2};

 with (obj)

 {

   function f()

   {

     return a;

   }

 }

 actual = f();

 expect = 2;

 addThis();

 /*

  * Like Section C, but with one more level of indirection -

  */

 status = 'Section D of test';

 var a = 1;

 var obj = {a:2, obj:{a:3}};

 with (obj)

 {

   with (obj)

   {

     function f()

     {

       return a;

     }

   }

 }

 actual = f();

 expect = 3;

 addThis();

 /*

  * Like Section C, but here we actually delete obj before calling f.

  * We still expect 2 -

  */

 status = 'Section E of test';

 var a = 1;

 var obj = {a:2};

 with (obj)

 {

   function f()

   {

     return a;

   }

 }

 delete obj;

 actual = f();

 expect = 2;

 addThis();

 /*

  * Like Section E. Here we redefine obj and call f under with (obj) -

  * We still expect 2 -

  */

 status = 'Section F of test';

 var a = 1;

 var obj = {a:2};

 with (obj)

 {

   function f()

   {

     return a;

   }

 }

 delete obj;

 var obj = {a:3};

 with (obj)

 {

   actual = f();

 }

 expect = 2;  // NOT 3 !!!

 addThis();

 /*

  * Explicitly verify that f exists at global level, even though

  * it was defined under the with(obj) block -

  */

 status = 'Section G of test';

 var a = 1;

 var obj = {a:2};

 with (obj)

 {

   function f()

   {

     return a;

   }

 }

 actual = String([obj.hasOwnProperty('f'), self.hasOwnProperty('f')]);

 expect = String([false, true]);

 addThis();

 /*

  * Explicitly verify that f exists at global level, even though

  * it was defined under the with(obj) block -

  */

 status = 'Section H of test';

 var a = 1;

 var obj = {a:2};

 with (obj)

 {

   function f()

   {

     return a;

   }

 }

 actual = String(['f' in obj, 'f' in self]);

 expect = String([false, true]);

 addThis();

 //-------------------------------------------------------------------------------------------------

 test();

 //-------------------------------------------------------------------------------------------------

 function addThis()

 {

   statusitems[UBound] = status;

   actualvalues[UBound] = actual;

   expectedvalues[UBound] = expect;

   UBound++;

   resetTestVars();

 }

 function resetTestVars()

 {

   delete a;

   delete obj;

   delete f;

 }

 function test()

 {

   enterFunc ('test');

   printBugNumber(BUGNUMBER);

   printStatus (summary);

   for (var i = 0; i < UBound; i++)

   {

     reportCompare(expectedvalues[i], actualvalues[i], statusitems[i]);

   }

   exitFunc ('test');

 }