195772 - undefined case of border conflict resolution should work the other way around

Status: RESOLVED INVALID

(Core :: Layout: Tables, defect, P3)

Description

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

In CSS2 / CSS 2.1 there are some undefined cases in the table border conflict
resolution algorithm for border collapsing.  Right now the way we resolve them
is the opposite of the way MacIE and Opera resolve them, and the MacIE / Opera
way makes very slightly more sense, since it fits with the model of things later
in the document drawing on top.  We should probably implement as though the end
of rule 4 said "When two elements of the same type disagree, use the border of
the element later in the source document."

Comment 1

[Bernd]

David, could you attach a testcase. I dont have MacIE and I do not trust Opera
at border collapse, every time I tested it against mozilla it was disaster.

Comment 2

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Attachment: testcase

Comment 3

[Bernd]

We render the testcase exactly like IE6 win. Should we really go after the minor
competitor? An argument to change the behaviour would be that the w3c clarifies
the spec and makes IE6 noncompliant. I somehow doubt that this will happen as
there are two interoperable implementations.

Comment 4

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

It's worth noting that WinIE doesn't implement the existing rules correctly.

Comment 5

[Bernd]

I am reluctant to change something that is not a bug at all, that breaks
compatibilty with IE win, where the w3c-style working did not do the necessary
homework by providing a clear and selfconsistent specification. For me the
current first come first serve model is perfectly valid especially under
incremental reflow conditions where we will suppress a color change when new
rows arrive. David if you get the w3c to specify this, (didn't you propose that
already in '99) I will work on this. 

Comment 6

[Bernd]

the css 2.1 defines this just the opposite to comment 0:
 
If border styles differ only in color, then a style set on a cell wins over one on a row, which wins over a row group, column, column group and, lastly, table. When two elements of the same type conflict, then the one further to the left (if the table's 'direction' is 'ltr'; right, if it is 'rtl') and further to the top wins.