312639 - 'overflow:scroll' stacking is now wrong

Status: RESOLVED FIXED

(Core :: Web Painting, defect)

Description

[Hixie (not reading bugmail)]

See http://www.hixie.ch/tests/adhoc/css/overflow/002.html

It seems we are now treating overflow:scroll boxes as if they formed a stacking
context, which is wrong per 2.1.

We should fix this for 1.5.

Comment 1

[Frank Wein [:mcsmurf]]

Just FYI, this regressed between 2005-05-30 06:00 and 2005-05-31 06:00.

Comment 2

[Robert O'Callahan (:roc) (email my personal email if necessary)]

I'm almost 100% sure it's because I started creating views for scrollframes in
bug 240276, which is now triggering bug 191830.

I don't think this can be fixed for 1.5. Fixing 191830 is much too much for
branch (although I plan to work on it soon for trunk). Removing the scrollframe
view would require some tricky work that would be timeconsuming and risky.

Comment 3

[Frank Wein [:mcsmurf]]

*sigh* make that 2005-03-30 and 2005-03-31 (instead of 2005-05-30 and 2005-05-31).

Comment 4

[Hixie (not reading bugmail)]

(Frank: Thanks!)

roc: Fair enough. Pity. We really should have caught this earlier; what's our
story on regression testing for catching this kind of thing?

Comment 5

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Frank says it's actually bug 288117. That's where I introduced the view for
scrollframes, so my analysis still holds.

Comment 6

[Robert O'Callahan (:roc) (email my personal email if necessary)]

We don't run systematic periodic layout regression tests. They probably would
have caught this bug if we had, since it's in your test suite, but my experience
has been (from when I was running automated tests) that the user testing we get
from nightly builds generally finds more regressions than automatic testing with
the test suites we have.

Comment 7

[Hixie (not reading bugmail)]

The two aren't mutually exclusive. :-) The more coverage the better.

Comment 8

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Yeah, I need to rescuscitate my regression testing scripts again ... and fix the
bugs that made painting nondeterministic on some of your testcases.

Comment 9

[Martijn Wargers (dead)]

I think this is WFM in my debug build that has the "frame display lists" patch in it (bug 317375).

Comment 10

[Steve England [:stevee]]

Testcase doesn't work with
Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.9a1) Gecko/20060124 Firefox/1.6a1 ID:2006012405
(both boxes red, no white text in top box)

Testcase does work with
Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.9a1) Gecko/20060126 Firefox/1.6a1 ID:2006012613
(both boxes greem, white 'A' in top box)

--> RESOLVED FIXED (by bug 317375)