501873 - if (window.event) gives a warning

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Akkana Peck]

Attachment: Minimal test. Hit shift-reload if it doesn't show the warning the first time.

To make event handling code work in IE as well as mozilla, in the event handler I have:

if (window.event) e = window.event;

But in 3.5 that now throws an error. Isn't this supposed to be the right way to check for JS capabilities (rather than browser version sniffing)?

Will attach a small test. Make the error console visible (and clear it), then load the page. Hit shift-reload a few times if needed (it warns most times but not every time).

Comment 1

[Akkana Peck]

> it warns most times but not every time

Ignore that part -- I was being dense. Of course it's the shift that shows the warning, not the reload (duh). Just type anything after loading the page to see the warning.

Comment 2

[Akkana Peck]

Further clarification: you'll only see the warning if javascript.options.strict is true.

Comment 3

[Blake Kaplan (:mrbkap) (inactive)]

I suspect that this was caused by bug 480185. window is a XOW and before that bug, XOWs used to use OBJ_GET_PROPERTY directly. Now they use JS_GetPropertyById which overrides cx->resolveFlags.

This is a hole in the API -- I think I need to be able to pass resolve flags into the Get and Set hooks (it'd be doubly nice if I could pass in a "preserve the current value" flag since that's what wrappers really want).

Comment 4

[Mike Taylor [:miketaylr]]

This is fixed now.