commit 31be8ffde4da304f7a2f684e57abb7e7c501ef3c
parent c50197b45e79abba28eccf25eb5eb8d795193842
Author: Anders Hartvoll Ruud <andruud@chromium.org>
Date: Tue, 21 Oct 2025 10:37:26 +0000
Bug 1995283 [wpt PR 55542] - Set explicit inheritance flags for inherit(), a=testonly
Automatic update from web-platform-tests
Set explicit inheritance flags for inherit()
When we apply 'inherit' in StyleBuilder::ApplyPhysicalProperty, we also
set some flags to ensure that inherited styles propagate "deep enough"
during style recalcs. The inherit() function has exactly the same
dependency, but StyleBuilder is not aware of that since inherit()
resolves earlier. Hence, we set the flags manually during
ResolveInheritInto instead.
I was also concerned that we had a bug related to the "independently
inherited" optimization, where we perform "light" style recalcs
for children in situations where only custom properties change
and nothing actually refers to those custom properties. However,
it turns out we already consider *any* arbitrary substitution function
(var(), attr(), env(), etc) as "possibly referencing a custom property",
so there was no bug there. (See MarkHasVariableReference).
Bug: 452071846
Change-Id: I033ae293ee10317fdc5c2e2faeaa163d1c0dccbb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7054668
Commit-Queue: Anders Hartvoll Ruud <andruud@chromium.org>
Reviewed-by: Steinar H Gunderson <sesse@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1532199}
--
wpt-commits: 082ef48403ebea0c585fcec8b44fb022eb94a71b
wpt-pr: 55542
Diffstat:
1 file changed, 94 insertions(+), 0 deletions(-)
diff --git a/testing/web-platform/tests/css/css-values/inherit-function-invalidation.html b/testing/web-platform/tests/css/css-values/inherit-function-invalidation.html
@@ -0,0 +1,94 @@
+<!DOCTYPE html>
+<title>CSS Values: The inherit() function (invalidation)</title>
+<link rel="help" href="https://drafts.csswg.org/css-values-5/#inherit-notation">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<main id=main>
+</main>
+
+<template id=parent_change_unregistered>
+ <style>
+ #outer {
+ --z: 2;
+ }
+ #target {
+ z-index: inherit(--z);
+ }
+ </style>
+ <div id=outer>
+ <div id=target>
+ </div>
+ </div>
+</template>
+<script>
+ test((t) => {
+ main.append(parent_change_unregistered.content.cloneNode(true));
+ t.add_cleanup(() => { main.replaceChildren(); });
+ assert_equals(getComputedStyle(target).zIndex, '2');
+ assert_equals(getComputedStyle(target).getPropertyValue('--z'), '2');
+ outer.style.setProperty('--z', '4');
+ assert_equals(getComputedStyle(target).zIndex, '4');
+ assert_equals(getComputedStyle(target).getPropertyValue('--z'), '4');
+ }, 'inherit() invalidates when values changes on parent element, inherited');
+</script>
+
+<!-- Like the previous test, but #target is buried deeper. -->
+<template id=parent_change_unregistered_deep>
+ <style>
+ #outer {
+ --z: 2;
+ }
+ #target {
+ z-index: inherit(--z, 7);
+ }
+ </style>
+ <div id=outer>
+ <div>
+ <div>
+ <div>
+ <div id=target></div>
+ </div>
+ </div>
+ </div>
+ </div>
+</template>
+<script>
+ test((t) => {
+ main.append(parent_change_unregistered_deep.content.cloneNode(true));
+ t.add_cleanup(() => { main.replaceChildren(); });
+ assert_equals(getComputedStyle(target).zIndex, '2');
+ outer.style.setProperty('--z', '4');
+ assert_equals(getComputedStyle(target).zIndex, '4');
+ }, 'inherit() invalidates when values changes on parent element, inherited, deeper');
+</script>
+
+<template id=parent_change_registered>
+ <style>
+ @property --z {
+ syntax: "<integer>";
+ inherits: false;
+ initial-value: 0;
+ }
+ #outer {
+ --z: 2;
+ }
+ #target {
+ z-index: inherit(--z, 7);
+ }
+ </style>
+ <div id=outer>
+ <div id=target>
+ </div>
+ </div>
+</template>
+<script>
+ test((t) => {
+ main.append(parent_change_registered.content.cloneNode(true));
+ t.add_cleanup(() => { main.replaceChildren(); });
+ assert_equals(getComputedStyle(target).zIndex, '2');
+ assert_equals(getComputedStyle(target).getPropertyValue('--z'), '0');
+ outer.style.setProperty('--z', '4');
+ assert_equals(getComputedStyle(target).zIndex, '4');
+ assert_equals(getComputedStyle(target).getPropertyValue('--z'), '0');
+ }, 'inherit() invalidates when values changes on parent element, non-inherited');
+</script>
