commit d926c9822c0520469452e36b99d7b2ef649321c8
parent e8ca07b12974bc0dfb339b34f746d86d4c742deb
Author: Koji Ishii <kojii@chromium.org>
Date: Thu, 27 Nov 2025 15:15:55 +0000
Bug 2002476 [wpt PR 56287] - [iframe] Support the fallback sizing, a=testonly
Automatic update from web-platform-tests
[iframe] Support the fallback sizing
This patch adds layout support for the fallback sizing.
No behavior changes as all changes are under a runtime flag.
Bug: 418397278
Change-Id: Ice2b5d2eafcae3561d7f18ce7978827aee94064d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7203483
Reviewed-by: Kent Tamura <tkent@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1550247}
--
wpt-commits: 7ffb48edfa87acbb4f7ee29685cb6529c8752f31
wpt-pr: 56287
Diffstat:
2 files changed, 47 insertions(+), 0 deletions(-)
diff --git a/testing/web-platform/tests/css/css-sizing/responsive-iframe/resources/iframe-contents-slow.html b/testing/web-platform/tests/css/css-sizing/responsive-iframe/resources/iframe-contents-slow.html
@@ -0,0 +1,19 @@
+<!doctype HTML>
+<head>
+<style>
+* { margin: 0 }
+</style>
+<meta name="responsive-embedded-sizing">
+<script>
+// Force a sleep for 0.5 second, to make sure the rest of the parsing is done
+// via a timer.
+const start = new Date().getTime();
+while (true) {
+ const now = new Date().getTime();
+ if (now - start > 500) {
+ break;
+ }
+}
+</script>
+</head>
+<div style="width: 100px; height: 400px"></div>
diff --git a/testing/web-platform/tests/css/css-sizing/responsive-iframe/responsive-iframe-fallback.tentative.html b/testing/web-platform/tests/css/css-sizing/responsive-iframe/responsive-iframe-fallback.tentative.html
@@ -0,0 +1,28 @@
+<!doctype HTML>
+<title>Test that the fallback size is used.</title>
+<link rel="author" href="mailto:kojii@chromium.org">
+<link rel="help" href="https://drafts.csswg.org/css-sizing/">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<style>
+iframe {
+ border: none;
+ contain-intrinsic-block-size: from-element 100px;
+}
+</style>
+<iframe id=target frameborder=0 src="resources/iframe-contents-slow.html"></iframe>
+<script>
+async_test(t => {
+ window.addEventListener('DOMContentLoaded', t.step_func(e => {
+ requestAnimationFrame(t.step_func(() => {
+ assert_equals(target.offsetHeight, 100);
+ }));
+ }));
+ window.addEventListener('load', t.step_func(e => {
+ requestAnimationFrame(t.step_func(() => {
+ assert_equals(target.offsetHeight, 400);
+ t.done();
+ }));
+ }));
+}, "The fallback size is used");
+</script>
