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[CSS21][17.5.2.1 Fixed table layout] Questions on fixed table layout algorithm

From: Gérard Talbot <www-style@gtalbot.org>
Date: Sun, 20 Nov 2011 16:22:31 -0800
Message-ID: <3dcd6e852bce346724cf37d14824f5b3.squirrel@gtalbot.org>
To: "W3C www-style mailing list" <www-style@w3.org>
Hello,

[nightly-unstable]
http://test.csswg.org/suites/css2.1/nightly-unstable/html4/table-layout-applies-to-006.htm

[RC6]
http://test.csswg.org/suites/css2.1/20110323/html4/table-layout-applies-to-006.htm

"
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.
(...)
"
section 17.5.2.1 Fixed table layout
http://www.w3.org/TR/CSS21/tables.html#fixed-table-layout

The algorithm given in section 17.5.2.1
http://www.w3.org/TR/CSS21/tables.html#fixed-table-layout
requires as input the set non-auto width of the table (and table borders
in border-collapse: collapse mode or cell spacing in border-collapse:
separate; we'll just assume we have such info) and then one of the
following 2 data:
- one set non-auto width of a column or
- one set non-auto width of a cell in first row

Now, in the table-layout-applies-to-006 testcase, we do not have one of
those 2 data. Because of that, I think the testcase is incorrect. Am I
wrong here?

---------

1- If width of each column is not determinable in a testcase where table
has a set non-auto width and a 'table-layout: fixed' declaration,
shouldn't 'table-layout: auto' algorithm (precision) be triggered and used
instead?
Browsers (Firefox 7.0.1, Opera 11.52) seem to disagree with me on this.

2- What is the meaning of an empty colgroup for CSS formatting purposes?
Colgroup can have 0 or more columns. I think an empty colgroup is totally
meaningless and worthless for use in the fixed table layout like in the
following code:

colgroup {width: 100px;}
...
<colgroup></colgroup>


3- Even if I have

colgroup {width: 400px;}
(...)
<colgroup>
  <col>
  <col>
</colgroup>

in a simple 2 column (2 cells per row) table with 'table-layout: fixed',
no one can establish how wide are respectively supposed to be first column
and second column. Am I wrong?

3 testpages on all this:

http://www.gtalbot.org/BrowserBugsSection/css21testsuite/table-layout-applies-to-006a.html

http://www.gtalbot.org/BrowserBugsSection/css21testsuite/table-layout-applies-to-006b.html

http://www.gtalbot.org/BrowserBugsSection/css21testsuite/table-layout-applies-to-006c.html


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

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

Web authors' contributions to CSS 2.1 test suite
http://www.gtalbot.org/BrowserBugsSection/css21testsuite/web-authors-contributions-css21-testsuite.html
Received on Monday, 21 November 2011 00:23:12 GMT

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