Clarification needed for inline boxes containing block boxes

Consider the following testcase:

data:text/html,<!DOCTYPE html><span style="padding: 0 20px; background: 
green; border: 2px solid red">aaa<div>bbb</div></span>

Note the lack of content inside the <span> after the <div>.

I see the following behavior on this testcase:

Gecko: no boxes generated for the <span> after the <div>.  The box
        before the <div> gets 20px left and right padding and both
        left and right borders.
Opera 9.6: A box with no left border, 20px right padding and no content
            is generated for the <span> after the <div>.  The box before
            the <div> has no right padding or border.
Safari 3.2.1: Generates a box before the div just like Opera, but no
               box after the div.
Webkit trunk from 2009-02-12: As Safari 3.2, but also generates an
                               inline box after the <div> with borders
                               and padding on both left and right.

IE7's behavior is pretty bizarre (e.g. the div gets the background 
behind it too, top borders disappear, etc).  I don't have IE8 on hand to 
test.

Modifying the testcase slightly by adding content to the <span> after 
the <div>, like so:

data:text/html,<!DOCTYPE html><span style="padding: 0 20px; background: 
green; border: 2px solid red">aaa<div>bbb</div>cc</span>

I see the following behavior:

Gecko: Boxes for the <span> generated both before and after the div.
        Both have 20px left and right padding and both have all 4
        borders.
Opera 9.6: As before, with the text 'cc' now in the box after the <div>.
Safari 3.2.1: As Opera for the box before the <div> and as Gecko for
               the box after.
Webkit trunk from 2009-02-12: As Safari 3.2.

It seems to me that section 9.2.1.1 isn't very clear, since no two UAs 
are doing it the same way.  We should probably clarify it somehow... 
 From my point of view, Opera's behavior here makes the most sense.  I 
would be quite happy to implement it in Gecko.

-Boris

Received on Thursday, 26 February 2009 02:47:37 UTC