313581 - JavaScript native function aliasing error

Status: RESOLVED DUPLICATE of bug 252291

(Firefox :: General, defect)

Description

[Retal]

User-Agent:       Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0; .NET CLR 1.1.4322; .NET CLR 2.0.50215)
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-GB; rv:1.7.12) Gecko/20050919 Firefox/1.0.7

When aliasing a native function in the following way:
getId = document.getElementById;

And then invoking the function using the alias in the following way:
getId("typewin").style.display = "none";

Then the following error is thrown in the JavaScript Console [filename edited]:
Error: uncaught exception: [Exception... "Illegal operation on WrappedNative prototype object"  nsresult: "0x8057000c (NS_ERROR_XPC_BAD_OP_ON_WN_PROTO)"  location: "JS frame :: file:///[...] :: writeSyntax :: line 30"  data: no]

Reproducible: Always

Steps to Reproduce:
1. Alias a native JavaScript function
2. Call the function using the new alias

Actual Results:  
Error: uncaught exception: [Exception... "Illegal operation on WrappedNative prototype object"  nsresult: "0x8057000c (NS_ERROR_XPC_BAD_OP_ON_WN_PROTO)"  location: "JS frame :: file:///[...] :: writeSyntax :: line 30"  data: no]

Expected Results:  
Executed the function as if not using the alias, without error.

Comment 1

[shutdown]

The constructs:
  element = document.getElementById(...);
and:
  getId = document.getElementById;
  element = getId(...);
will produce different results.

The former supplies |document| as |this| value for the method. So it succeeds.
The later supplies the global object (i.e. |window|) as |this| value for the
method. It will fail because the method does not accept such |this| value.

This bug should be resolved as INVALID.

Comment 2

[Retal]

Sorry for the mistake.