527017 - window.onhashchange = app.locationHashChanged; : inside app.locationHashChanged, this == window

Status: RESOLVED INVALID

(Firefox :: General, defect)

Description

[chameleon]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2b1) Gecko/20091029 Firefox/3.6b1 (.NET CLR 3.5.30729)
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2b1) Gecko/20091029 Firefox/3.6b1 (.NET CLR 3.5.30729)

Firefox 3.6b1 ONLY bug

The following code alerts on 3.6b1 "It doesn't work...".
Other browsers (firefox 3.5.x too) work fine because execute other piece of code.

var app = {
	func : function() { alert('It works!'); },
	locationHashChanged : function() { if (this == window) alert("It doesn't work..."); else this.func(); }
};

// for Firefox 3.6 only
if ("onhashchange" in window)
	window.onhashchange = app.locationHashChanged;
// for **** only
else {
	var currentHash = location.hash;
	setInterval('if (currentHash != location.hash) { currentHash = location.hash; app.locationHashChanged(); }', 100);
}

Reproducible: Always

Actual Results:  
this inside locationHashChanged function is this == window

Expected Results:  
this inside locationHashChanged function must be this == app

Comment 1

[Justin Lebar (not reading bugmail)]

I think what you're observing here are the general semantics of Javascript.

When you call |app.locationHasChanged()| the |this| argument will be |app|, as you expect.  But setting window.onhashchange to app.locationHashChanged basically sets a function pointer straight to the app.locaitonHashChanged function.  To get |app| to be the |this| argument on hashchange, I think you could do

  window.onhashchange = function() { app.locationHashChanged(); };