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Re: 'alt' text rendering not clearly defined

From: Eira Monstad <eira@synth.no>
Date: Tue, 03 Mar 2009 08:25:46 +0100
To: Arron Eicholz <Arron.Eicholz@microsoft.com>
Cc: public-css-testsuite@w3.org
Message-ID: <a9b7d6ec97e69b61298591efce53e322@synth.no>

On Mon, 2 Mar 2009 17:58:26 -0800, Arron Eicholz
<Arron.Eicholz@microsoft.com> wrote:
> http://www.w3.org/Style/CSS/Test/CSS2.1/current/html4/bidi-alt-001.htm
> 
> This test case is not clearly defined in the specification.
> 
> CSS 2.1 Conformance: Requirements and Recommendations, 3.1 [1] states
that
> replaced elements are outside the scope of the CSS formatting model. This
> means that if 'alt' text is treated as a replaced element then the case
is
> incorrect.
> 
> If we look at the HTML 4.01 specification, section 13.8 [2], it states
> that 'alt' text when rendered should be rendered as content. From this
> definition it puts the 'alt' text into a different category in section
3.1
> [1] of the CSS specification. The "Content" definition states that it
"may
> include text" then continuing on further... The "Rendered content"
> definition states that "Rendered content may also be alternate text for
an
> element ...". Because of the use of the word "may" it makes this test
case
> optional based on the definition of MAY in the RFC2119 [3].
> 
> The test case needs to be removed or updated to allow it to pass if
styles
> do not apply to 'alt' text.

I suppose it could be made valid by adding a conditional to the pass
condition, though that would make the pass condition more complex than I'd
prefer: "If you see any blue below, then (...). If you see no blue, then
the lines may be different and it's still a pass". That would require that
if the color is applied, the bidi properties must also be applied.

Before updating, though, I'd like to hear if anyone has better suggestions
on how to rewrite this to avoid the too-complex pass condition.

- Eira
Received on Tuesday, 3 March 2009 07:27:38 GMT

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