964222 - Adjust the padding- and content-areas to follow the border with border-radius

Status: NEW

(Core :: Layout: Block and Inline, defect, P4)

Description

[Mats Palmgren (inactive)]

Attachment: Testcase #1

See the attached testcase.  I find it ugly that the text overflows
the border.  Also, it seems to me this violates the essence of the
Box Model which is that content/padding/border areas are seamless
and do not overlap.  http://www.w3.org/TR/CSS2/box.html
(Granted, it speaks only of "rectangles", bur presumably because
border-radius was added later?)

The Corner Shaping section in the border-radius spec supports that view:
http://www.w3.org/TR/css3-background/#corner-shaping
"The padding edge (inner border) radius is the outer border radius
minus the corresponding border thickness."  [...]
"Likewise the content edge radius is the padding edge radius minus
the corresponding padding"

So it seems to me our current rendering is just a bug that we
should fix.

Comment 1

[Mats Palmgren (inactive)]

Attachment: Expected result

It doesn't look that hard to fix this, btw.
It took a 10-line patch to shorten the line box to account for
the border radius to produce this result. (I cheated and only
fixed the top-left corner though ;-) ).