378933 - [BC] overdrawn (but not repainted) border-collapse border on cell above missing cell

Status: RESOLVED FIXED

(Core :: Layout: Tables, defect)

Description

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

Attachment: tetscase

I'm seeing some problems in a rather simple testcase of border-collapsed borders with empty cells.

In the testcase, every cell has the contents "X", but rows have different numbers of cells.  Ever cell should have a border.  The bottommost cell in the middle column gets its border drawn incorrectly:
 * the side border is drawn all the way to the bottom of the table (but the part that shouldn't be drawn isn't repainted correctly if only it is invalidated)
 * the bottom border is not drawn

Steps to reproduce: load attached testcase, and scroll down to the table

Expected results:
 1. cell in middle column, third row, should have a bottom border
 2. there should be no border separating the middle and right columns in the fourth and fifth rows

Actual results:
 1. cell in middle column, third row, has no bottom border
 2. there is a border separating the middle and right columns in the fourth and fifth rows (but when scrolling so that the only invalidation that happens is within the fourth and fifth rows, the incorrectly drawn part is not painted)

Comment 1

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

See also bug 378935 and bug 378937 on similar testcases.

Comment 2

[Bernd]

fixed by bug 378935