358092 - captureEvents(), releaseEvents(): False deprecation warning for scripts based on object-detection

Status: RESOLVED DUPLICATE of bug 358091

(Firefox :: General, defect)

Description

[Walter Zorn]

User-Agent:       Opera/9.02 (Windows NT 5.1; U; en)
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1) Gecko/20061010 Firefox/2.0

Presently, the JS-console-warning "Use of captureEvents() is deprecated" without reason is displayed for scripts based on object detection rather than on browser detection. That is, even if a script doesn't rely on these functions, but rather checks for their existence before calling them.

This is annoying for JS developers who receive a lot of false alarms by users, though their scripts aren't really broken (yes, I'm a victim of this :)). And it is disturbing for less-experienced JS developers.


Reproducible: Always

Steps to Reproduce:
JavaScript:

g_oldMoveFunc = document.onmousemove; // Store reference to previous handler
if(document.captureEvents)
    document.captureEvents(Event.MOUSEMOVE);
document.onmousemove = someMoveFunc;

Actual Results:  
A false "Use of captureEvents() is deprecated" warning is written to the JS console.

Expected Results:  
The warning should not appear for the JS lines above. Reason: If a browser doesn't support captureEvents(), line 2 will evaluate to false, and the browser cannot enter line 3.

Nothing. Just ignore line 3.

Comment 1

[Walter Zorn]

*** This bug has been marked as a duplicate of 358091 ***