914450 - TabSelect event listener can cause exceptions due to not finding an element with view id

Status: RESOLVED FIXED

(Firefox for Metro Graveyard :: Pan and Zoom, defect)

Description

[Boris Zbarsky [:bzbarsky]]

This causes test failures once we xpconnect eating those exceptions.

Comment 1

[Boris Zbarsky [:bzbarsky]]

Attachment: findElementWithViewId can throw if it finds nothing, so be careful to catch that exception.

Comment 2

[Brian R. Bondy [:bbondy]]

Comment on attachment 801972 [details] [diff] [review]
findElementWithViewId can throw if it finds nothing, so be careful to catch that exception.

Review of attachment 801972 [details] [diff] [review]:
-----------------------------------------------------------------

::: browser/metro/base/content/apzc.js
@@ +57,3 @@
>          windowUtils.setDisplayPortForElement(0, 0, ContentAreaObserver.width,
>                                               ContentAreaObserver.height,
> +                                             element);

Doesn't windowUtils.setDisplayPortFor uElement also throw if passed in an undefined element?

Comment 3

[Boris Zbarsky [:bzbarsky]]

Comment on attachment 801972 [details] [diff] [review]
findElementWithViewId can throw if it finds nothing, so be careful to catch that exception.

It would if that actually happened, sure.

But findElementWithViewId will never return a null element if the passed-in id is 1.  So in this case, if we didn't throw an exception and break we know we have an actual element.

Comment 4

[Brian R. Bondy [:bbondy]]

Comment on attachment 801972 [details] [diff] [review]
findElementWithViewId can throw if it finds nothing, so be careful to catch that exception.

Review of attachment 801972 [details] [diff] [review]:
-----------------------------------------------------------------

r+ given that the root element will always implement nsIDOMElement and so findElementWithViewId won't return undefined.

Comment 5

[Boris Zbarsky [:bzbarsky]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/9e1c03f7953a

Comment 6

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/9e1c03f7953a