967803 - getComputedStyle(el).top returns length rather than auto for position:absolute;top:auto (different from WebKit)

Status: RESOLVED INVALID

(Core :: DOM: CSS Object Model, defect)

Description

[Elie Roux]

Attachment: index.html

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:26.0) Gecko/20100101 Firefox/26.0 Iceweasel/26.0 (Beta/Release)
Build ID: 20131215090532

Steps to reproduce:

I tested the attached simple code with Firefox 24 and 26.


Actual results:

the result is first auto then 8px


Expected results:

In webkit, the result is auto then auto. An application I'm using was relying on webkit's behaviour (see https://github.com/chaosim/splitter/issues/1).

Comment 1

[Boris Zbarsky [:bzbarsky]]

http://dev.w3.org/csswg/cssom/#resolved-value lists "top" in the list of properties for which getComputedStyle returns the used value, not the computed value.

So I believe our behavior is in fact correct per that spec draft.

Comment 2

[Boris Zbarsky [:bzbarsky]]

Also see https://bugs.webkit.org/show_bug.cgi?id=29084 (which jQuery is currently working around, apparently)

Comment 3

[Elie Roux]

Ok, it indeed seems to be a bug in Webkit, sorry for the noise! I don't seem to be able to close it as "invalid", can someone please do it?

Thank you,