Re: [RC6] width-applies-to-005 : comments

Le Mer 7 novembre 2012 19:16, "Gérard Talbot" a écrit :
> Arron,
>
> [RC6]
> http://test.csswg.org/suites/css2.1/20110323/html4/width-applies-to-005.htm
>
> [nightly-unstable]
> http://test.csswg.org/suites/css2.1/nightly-unstable/html4/width-applies-to-005.htm
>
> This test is rather weak and unreliable for several reasons:
>
> - the CSS table has only 1 empty cell, only 1 row, no column and 1
> column-group element
> - table-layout: fixed is declared but the table has no set width, in
> which case the spec states that
> "
> The table's width may be specified explicitly with the 'width' property.
> A value of 'auto' (for both 'display: table' and 'display:
> inline-table') means use the automatic table layout algorithm.
> "
> 17.5.2.1 Fixed table layout
> http://www.w3.org/TR/CSS21/tables.html#fixed-table-layout
>
>
> So, when I worked on that test for review, I created these 2 tests (or
> rather, 2 versions of that same test):
>
> http://www.gtalbot.org/BrowserBugsSection/css21testsuite/width-applies-to-005-with-width-GT.xht
>
> http://www.gtalbot.org/BrowserBugsSection/css21testsuite/width-applies-to-005-withOUT-width-GT.xht
>
> in which both tests have 2 non-empty cells inside 2 rows and 2 declared
> table-column elements inside one column-group element. The only
> difference between those 2 tests is whether the table element has a set
> width or not. And such difference has a great layout impact on both
> versions of such test: Firefox 16.0.2, Opera 12.10, Chrome 22.0.1229.94,
> IE9, IE10 render both versions of such test respectively the same. FWIW,
> I think Opera 12.10 renders
> http://www.gtalbot.org/BrowserBugsSection/css21testsuite/width-applies-to-005-withOUT-width-GT.xht
> as I expected; I am unsure as to why other browsers render a 2in wide
> black rectangle in width-applies-to-005-withOUT-width-GT.xht

With more thinking and more testing, I think we should raise a spec
issue here.

17.3 Columns states

"
'width'
    The 'width' property gives the minimum width for the column.
"
http://www.w3.org/TR/CSS21/tables.html#columns

Strangely, why is it explicitingly mentioning column and not mentioning
column group?

Later, in 17.5.2.1
http://www.w3.org/TR/CSS21/tables.html#fixed-table-layout

"
In the fixed table layout algorithm, the width of each column is
determined as follows:

    A column element with a value other than 'auto' for the 'width'
property sets the width for that column.
    Otherwise, a cell in the first row with a value other than 'auto'
for the 'width' property determines the width for that column. If
the cell spans more than one column, the width is divided over the
columns.
    Any remaining columns equally divide the remaining horizontal table
space (minus borders or cell spacing).
"

So, just setting width to a column-group element has no importance, no
relevance, no rendering impact.

I am now convinced there is a spec issue here. Otherwise, I do not know
when and how width can be set onto a table-column-group when in the
Fixed table layout algorithm.

On top of all this...

We have also at least one test which contradicts, collides with
width-applies-to-005 test:

http://test.csswg.org/suites/css2.1/nightly-unstable/html4/fixed-table-layout-013.htm

which states/with its stated goal: "Specified column-group width is
ignored in fixed table layout."

Gérard
-- 
Contributions to the CSS 2.1 test suite:
http://www.gtalbot.org/BrowserBugsSection/css21testsuite/

CSS 2.1 Test suite RC6, March 23rd 2011:
http://test.csswg.org/suites/css2.1/20110323/html4/toc.html

CSS 2.1 test suite harness:
http://test.csswg.org/harness/

Contributing to to CSS 2.1 test suite:
http://www.gtalbot.org/BrowserBugsSection/css21testsuite/web-authors-contributions-css21-testsuite.html

Received on Thursday, 8 November 2012 00:49:56 UTC