10573 - onerror function doesn't work like it does for 4.x

Status: VERIFIED FIXED

(Core :: DOM: UI Events & Focus Handling, defect, P3)

Description

[Syd Logan]

I added the file onerror.js tonight, but it doesn't work like it does in 4.x.
This code came from Danny Goodman's JavaScript Bible, and should display a
dialog when it encounters an error in JS code. But it doesn't. To add the js
file to a xul file, try

<html:script language="JavaScript" src="resource:/res/samples/onerror.js"/>

Comment 1

[Mike McCabe]

Passing this on to Roger...

Roger - this could end up being something for the imbedding; I don't think the
core engine has ever defined onError.  But it'll likely interact with
exceptions; the best compromise that I found was to have uncaught exceptions
(Just when does it become uncaught?  It's a puzzler...) call the onError
handler.  One way to do this is to have exceptions always look just like
JavaScript errors always have to imbedding code that doesn't know look for an
associated exception value.

Comment 2

[rogerl (gone)]

Uncaught exceptions - defined as those that make it out to the API invocation
level are turned into errors (marked as having exception-al birthright). The
embedding simply needs to respond to these in the same way as past JS errors.
The onerror event handler does not seem to be hooked up right now, but things
should just work fine when it is; I don't see any reason for the engine to get
into the onerror game since the current mechanism will work fine? I'm sending
the bug onto EventHandling since the initial complaint is that the onerror stuff
simply doesn't work, regardless of exceptions.

Comment 3

[ekrock's old account (dead)]

Moving M16.

Comment 4

[leger]

Setting the keyword all open [4.xp] bugs to 4xp.

Comment 5

[leger]

Updating QA contact.

Comment 6

[joki (gone)]

Okay, I've added the onerror event as well as setting it up so that 'return 
true' from inside JS will surpress the error message (as opposed to 'return 
false' for most every other event).  However, in accordance with the DOM Level 2 
spec, the new proper way to accomplish this is to call event.preventDefault().  
PreventDefault works consistently for all events.

Comment 7

[ckritzer (gone)]

Mass update:  changing qacontact to [e-mail]

Comment 8

[Loco]

Updating QA Contact.

Comment 9

[Hixie (not reading bugmail)]

Reassigning QA Contact for all open and unverified bugs previously under Lorca's
care to Gerardo as per phone conversation this morning.

Comment 10

[Madhur Bhatia]

QA contact updated

Comment 11

[luis rincon]

verified on build 2001-07-30-03-trunk