From: Ryosuke Niwa <[email protected]<mailto:[email protected]>>
Date: Tuesday, August 20, 2013 1:59 PM
To: Bruno de Oliveira Abinader 
<[email protected]<mailto:[email protected]>>
Subject: Re: [webkit-dev] Proposal: Move CSS3 Text Decoration properties out of 
CSS3_TEXT feature flag / remove vendor prefix

On Tue, Aug 20, 2013 at 10:08 AM, Bruno de Oliveira Abinader 
<[email protected]<mailto:[email protected]>> wrote:
The CSS Level 3 Text Decoration specification [1] has recently changed status 
to "W3C Candidate Recommendation", which means it has been widely reviewed and 
is ready for implementation (so we can expect no further syntax changes). So 
far the following properties from that specification are implemented behind a 
feature flag (CSS3_TEXT):

-webkit-text-decoration (shorthand)
-webkit-text-decoration-line
-webkit-text-decoration-style
-webkit-text-decoration-color
-webkit-text-underline-position

Please notice all of these properties are implemented with vendor prefix on 
WebKit. There are other properties implemented behind CSS3_TEXT feature flag 
that do not belong to CSS Level 3 Text Decoration specification and thus are 
not going to be handled in this proposal. Said this, I would like to propose 
the following changes:

I'd like to know how well these properties work well in contenteditable 
regions.  Namely, when a user edits text with text decoration color, line 
style, etc... would it properly preserve them?

I believe this requires some discussion – currently the HTML Editing APIs [1] 
specification does not provide methods for modifying text decoration's style 
and color. That said, these prefixed properties implementations are not 
currently handled in EditingStyle – but if you paste HTML code containing these 
on an editable element, it would preserve the properties information (I could 
write a test in editing/ to verify that).

1) Move the aforementioned properties out of CSS3_TEXT feature flag - currently 
it is enabled by default on EFL/GTK ports, must obtain acknowledgement from all 
other ports maintainers.

How complete and compatible is our implementation with other browsers and with 
respect to the W3C specification?  Does W3C have tests?  If so, do we pass all 
of them?

In terms of completeness, we are not providing support for all properties 
specified in CSS Level 3 Text Decoration specification, but for the ones we 
have implemented, those are full implementations (with exception of "blink" 
value from text-decoration-line which is valid but ignored, as in CSS 2.1 
text-decoration implementation in WebKit).

Speaking of compatibility, besides WebKit, Gecko implements text-decoration 
shorthand unprefixed, text-decoration{-line,-style-color} prefixed (-moz-), and 
does not implement text-underline-position (which is only implemented on 
Trident). The syntax for values is the same for all implementations, and does 
so for visual expectations/computed styles.

As for W3C tests, according to [2] there are currently no tests for latest 
release, but on the nightly unstable [3] I could find at least 12 tests, all 
passing for now (w/ exception of text-decoration-line-014 which expects text to 
blink).


2) Remove the vendor prefix from these properties – probably the only 
side-effect that I see is that the current computed style from text-decoration 
(which is implemented according to CSS 2.1 specification) would change to 
support the shorthand implementation (as currently implemented on Blink), thus 
requiring us to modify some layout test results that depends on text-decoration 
computed style.

Do EFL and GTK ports not want to support the prefixed version?  It seems 
desirable to keep both the prefixed version and the unprefixed version.

I'd feel comfortable with whatever decision the port maintainers decide, though 
un-prefixing these properties would match Blink's implementation.

Links:
[1] https://dvcs.w3.org/hg/editing/raw-file/tip/editing.html
[2] http://www.w3.org/Style/CSS/Test/Overview.en.html
[3] http://test.csswg.org/suites/css-text-decor-3/nightly-unstable/

Best regards,
Bruno
_______________________________________________
webkit-dev mailing list
[email protected]
https://lists.webkit.org/mailman/listinfo/webkit-dev

Reply via email to