1871609 - Border-collapsed table's border width recalculation is stateful

Status: VERIFIED FIXED

(Core :: Layout: Tables, defect)

Description

[David Shin[:dshin]]

Attachment: Minimum Reproducible Case

STR:

1. Open the testcase
2. Note table shape
3. Hover over "one"
4. Note thick border between "one" and "two"
5. Hover elsewhere
6. Note table shape
   Expected: 2) and 6) are identical
   Actual: 6) has more space between "one" and "two"

Comment 1

[David Shin[:dshin]]

Probably happened since bug 1464928. The testcase is derived from a test added from that bug.
The path responsible was added from bug 41262 - stored border widths are stateful, storing the max of the result of GetBorderWidth and the incoming border (Which is 0 in this case). GetBorderWidth returns a halved value, hence why the final table's gap between cells is half of 20px.
The original test case doesn't suffer from this because it works with 1px borders, of which half is rounded down to 0.

Comment 2

[David Shin[:dshin]]

Attachment: Bug 1871609: On calculating border-collapsed table's borders, reset max-seen width. r=#layout

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/84b76f80bf96
On calculating border-collapsed table's borders, reset max-seen width. r=TYLin

Comment 4

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Created web-platform-tests PR https://github.com/web-platform-tests/wpt/pull/46138 for changes under testing/web-platform/tests

Comment 5

[Cristian Tuns]

Backed out for causing wr failures in /css/css-tables/*

• Backout link
• Push with failures
• Failure Log
• Failure line: TEST-UNEXPECTED-FAIL | /css/css-tables/table_grid_size_col_colspan.html | Testing http://web-platform.test:8000/css/css-tables/table_grid_size_col_colspan.html == http://web-platform.test:8000/css/css-tables/table_grid_size_col_colspan-ref.html
• Failure Log 2
• Failure line 2: TEST-UNEXPECTED-FAIL | /css/css-tables/tentative/paint/collapsed-border-large-cell.html | Testing http://web-platform.test:8000/css/css-tables/tentative/paint/collapsed-border-large-cell.html == http://web-platform.test:8000/css/css-tables/tentative/paint/collapsed-border-large-cell-ref.html

Comment 6

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Upstream PR was closed without merging

Comment 7

[David Shin[:dshin]]

Changes made, try run looks good (Failure cases don't even use table, so it seems unrelated)

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/39658819ee60
On calculating border-collapsed table's borders, reset max-seen width. r=TYLin

Comment 9

[Daniel Holbert [:dholbert]]

(In reply to David Shin[:dshin] from comment #7)

Changes made, try run looks good (Failure cases don't even use table, so it seems unrelated)

Yeah, the R5 run there looks like it's a version of bug 1895092, so it's likely an infra issue and not something you need to worry about. (It matches the "bad" pattern from bug 1895092 comment 16.)

Comment 10

[Narcis Beleuzu [:NarcisB]]

https://hg.mozilla.org/mozilla-central/rev/39658819ee60

Comment 11

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Upstream PR merged by moz-wptsync-bot

Comment 12

[Ardelean Oana, Desktop QA [:oardelean]]

Issue is reproducible on a 2024-05-05 Nightly build on Windows 10.
Verified as fixed on Firefox Nightly 128.0a1 and Firefox 127.0b2 on Windows 10, macOS 12, Ubuntu 22.