Re: [css2] Fixed table layout: width distribution between non-auto columns

On Thursday 2014-11-27 17:30 +0000, Simon Sapin wrote:
> In http://dev.w3.org/csswg/css2/tables.html#fixed-table-layout
> >The width of the table is then the greater of the value of the
> >'width' property for the table element and the sum of the column
> >widths (plus cell spacing or borders). If the table is wider than the
> >columns, the extra space should be distributed over the columns.
> 
> This does not say *how* the space is distributed. I assumed it was
> equally, but Firefox, Chromium, Safari and IE seem to have interop
> to make it proportional to the widths of the columns “so far”.

For what it's worth, the Gecko behavior for handling unassigned
extra space from the table width in table-layout:fixed is:

 1. if some columns do not have specified width, distribute it
    equally among them

 2. otherwise, if some columns have non-zero <length> widths,
    distribute the excess width to them, proportionally to the
    widths

 3. otherwise, if some columns have non-zero <percentage> widths,
    distribute the excess width to them, proportionally to the
    widths

 4. otherwise, distribute the excess width equally to the zero-width
    columns

The code for this is reasonably readable, I think (since it's
basically in one place):
https://hg.mozilla.org/mozilla-central/file/be1f49e80d2d/layout/tables/FixedTableLayoutStrategy.cpp#l331

-David

-- 
𝄞   L. David Baron                         http://dbaron.org/   𝄂
𝄢   Mozilla                          https://www.mozilla.org/   𝄂
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