Re: [CSS21] Objection over Issue 203 (clearance and hypothetical position) (Was: Re: [CSS21] Clearance - the missing manual)

On Thursday 2011-03-17 23:40 +0100, Anton Prowse wrote:
> I ask that the WG reopen Issue 203 and re-evaluate it without
> reference to that cited, irrelevant post.  The Minutes and
> Resolutions in [2] seem to indicate that the WGs currently proposed
> resolution is not based on the cited post anyhow, and is instead
> arose from an e-mail that David Baron wrote to Ian Hickson.  I
> request that the points from that e-mail be presented publicly on
> this mailing list, since it's beginning to seem that Issue 203 has
> been hijacked by a different issue which has not yet been made
> public, and resolved with a proposal that bears no obvious
> relationship to the original problem.

The email, in full (which I originally wrote as private email), is
below.  Ian's response was very short and basically said he doesn't
remember the original discussions well enough to be able to add
anything to the current one.

Apologies for not publishing this earlier; I meant to do so.

-David

> Date: Tue, 25 Jan 2011 17:28:58 -0800
> From: "L. David Baron" <dbaron@dbaron.org>
> To: Ian Hickson <ian@hixie.ch>
> Subject: clear issues
> 
> We're having a fun discussion in the CSS working group (just a
> subgroup meeting to discuss test status right now) about a margin
> collapsing issue.
> 
> The key info is mostly in:
> http://wiki.csswg.org/test/css2.1/blocking/margin-collapse
> https://bugzilla.mozilla.org/show_bug.cgi?id=376365
> 
> The basic problem (see comment 15 and comment 14 of the bug) is that
> the edit to the spec that was intended to make these three tests
> valid doesn't seem to actually have done what was intended, because
> "hypothetical position" is a position "within its parent block".
> 
> I think the intent was to say that the hypothetical position is
> relative to the block formatting context or an absolute position.
> However, if it's relative to the parent block, then the hypothetical
> position is at y=0 within the parent block (at least looking at
> margin-collapse-164, which is perhaps the simplest of the cases), so
> the fix that was intended to prevent margins from being eaten
> doesn't cause them to be.
> 
> 
> I have mixed feelings about what to do about this:
> 
> We have a patch for Gecko that we could land after Firefox 4.  It
> fixes those three tests, but it also breaks Acid2.  The IE folks say
> that it caused some Web-compatibility issues as well (although it's
> not clear how major they are) when they tried fixing the bug.
> 
> It turns out it doesn't block CSS 2.1 entering PR since there are
> two PDF implementations that pass the tests (ugh).  But we should
> still figure out whether we want to fix the spec (to match the
> intent of the change) or the tests (to match the pretty-reasonable
> Microsoft interpretation of the spec).  (Or we could postpone
> changing either for a bit...)
> 
> 
> I'm curious if you have any thoughts on this.
> 
> -David
> 
> -- 
> L. David Baron                                 http://dbaron.org/
> Mozilla Corporation                       http://www.mozilla.com/

-- 
L. David Baron                                 http://dbaron.org/
Mozilla Corporation                       http://www.mozilla.com/

Received on Thursday, 17 March 2011 23:14:47 UTC