commit db2bb86dc8feeb0d5a7e044f47777bf72099ad3e
parent 1b406fb2d1a3effdf39371f92dc573b0c5d400f2
Author: Morten Stenshorne <mstensho@chromium.org>
Date: Wed, 19 Nov 2025 04:55:44 +0000
Bug 2000724 [wpt PR 56075] - Finalize column-height:0 support., a=testonly
Automatic update from web-platform-tests
Finalize column-height:0 support.
Spec resolution here:
https://github.com/w3c/csswg-drafts/issues/12787#issuecomment-3530646130
In short: allow column-height:0, so that rows may become 0px tall. The
fragmented flow is still guaranteed progress, since a fragmentainer has
to accept at least 1px of content, according to
https://drafts.csswg.org/css-break/#breaking-rules
This was pretty much what we were already doing, but there was a problem
before the very first zero-height row, in that we'd consider it to be
full even before layout.
Bug: 403183884
Change-Id: I5cf64697b0f3e1788fea43f95abfed912a9d571e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7156852
Reviewed-by: Ian Kilpatrick <ikilpatrick@chromium.org>
Commit-Queue: Morten Stenshorne <mstensho@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1546150}
--
wpt-commits: 119ac9fd841b9e4cd198c5e13576e6707600fdf9
wpt-pr: 56075
Diffstat:
3 files changed, 42 insertions(+), 0 deletions(-)
diff --git a/testing/web-platform/tests/css/css-multicol/column-height-021.html b/testing/web-platform/tests/css/css-multicol/column-height-021.html
@@ -0,0 +1,11 @@
+<!DOCTYPE html>
+<title>column-height: 0</title>
+<link rel="author" title="Morten Stenshorne" href="mailto:mstensho@chromium.org">
+<link rel="help" href="https://drafts.csswg.org/css-multicol-2/#ch">
+<link rel="help" href="https://drafts.csswg.org/css-multicol-2/#cwr">
+<link rel="match" href="../reference/ref-filled-green-100px-square.xht">
+<p>Test passes if there is a filled green square and <strong>no red</strong>.</p>
+<div style="position:relative; columns:2 / 0; width:100px; gap:99px 0; column-fill:auto; background:red;">
+ <div style="height:4px; background:green;"></div>
+ <div style="position:absolute; top:1px; left:0; width:100%; height:98px; background:green;"></div>
+</div>
diff --git a/testing/web-platform/tests/css/css-multicol/column-height-022.html b/testing/web-platform/tests/css/css-multicol/column-height-022.html
@@ -0,0 +1,12 @@
+<!DOCTYPE html>
+<title>column-height: 0</title>
+<link rel="author" title="Morten Stenshorne" href="mailto:mstensho@chromium.org">
+<link rel="help" href="https://drafts.csswg.org/css-multicol-2/#ch">
+<link rel="help" href="https://drafts.csswg.org/css-multicol-2/#cwr">
+<link rel="match" href="../reference/ref-filled-green-100px-square.xht">
+<p>Test passes if there is a filled green square and <strong>no red</strong>.</p>
+<div style="position:relative; columns:2 / 0; padding-bottom:1px; border-bottom:1px solid green; width:100px; gap:49px 0; column-fill:auto; background:red;">
+ <div style="height:6px; background:green;"></div>
+ <div style="position:absolute; top:1px; left:0; width:100%; height:48px; background:green;"></div>
+ <div style="position:absolute; top:50px; left:0; width:100%; height:48px; background:green;"></div>
+</div>
diff --git a/testing/web-platform/tests/css/css-multicol/column-height-023.html b/testing/web-platform/tests/css/css-multicol/column-height-023.html
@@ -0,0 +1,19 @@
+<!DOCTYPE html>
+<title>column-height: 0</title>
+<link rel="author" title="Morten Stenshorne" href="mailto:mstensho@chromium.org">
+<link rel="help" href="https://drafts.csswg.org/css-multicol-2/#ch">
+<link rel="help" href="https://drafts.csswg.org/css-multicol-2/#cwr">
+<link rel="match" href="../reference/ref-filled-green-100px-square.xht">
+<p>Test passes if there is a filled green square and <strong>no red</strong>.</p>
+<div style="columns:2 / 0; width:100px; gap:20px 0; column-fill:auto; background:red;">
+ <div style="contain:size; height:20px; background:green;"></div>
+ <div style="contain:size; height:20px; background:green;"></div>
+ <div style="contain:size; height:20px; background:green;"></div>
+ <div style="contain:size; height:20px; background:green;"></div>
+ <div style="contain:size; height:20px; background:green;"></div>
+ <div style="contain:size; height:20px; background:green;"></div>
+ <div style="contain:size; height:20px; background:green;"></div>
+ <div style="contain:size; height:20px; background:green;"></div>
+ <div style="contain:size; height:20px; background:green;"></div>
+ <div style="contain:size; height:20px; background:green;"></div>
+</div>
