Bug 74811 – 'this' object is sometimes the DOMWindow when it shouldn't be

• Status: NEW
• Component: JavaScriptCore

[Timothy Hatcher]

I've been hitting an odd bug in the Web Inspector's TreeOutline (very old and stable code) that calls a function on this, but the this object inside the function is sometimes the window and not the 'this' from the callee.

Changing the code from:

this.onpopulate();

To:

this.onpopulate.call(this);

Which fixes it 100%. Otherwise it only works fine 95-99% of the time, and randomly seems to forget the 'this' object.

This is with TOT r103101.

[Timothy Hatcher]

Obviously the callee has the right 'this' object, otherwise it would throw an exception calling "onpopulate".

I haven't been able to narrow it down to a test case yet. If you want to reproduce it, contact me.

[Timothy Hatcher]

<rdar://problem/10592017>

[Simon Fraser (smfr)]

Do you have  regression range?

[Timothy Hatcher]

No, it isn't 100% reproducible so it would be time consuming to find the range.