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Merged
simonwuelker merged 1 commit into from
Nov 21, 2025
Merged

layout: Preserve cached layout results of undamaged descendants #40797

simonwuelker merged 1 commit into from
Nov 21, 2025

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@Loirooriol
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@Loirooriol Loirooriol commented Nov 21, 2025 •
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We were previously clearing the cached layout results when the element, an ancestor, or a child had relayout damage. Now we will only clear the cache if the relayout damage is in the element or a descendant.

Testing: Unneeded, no behavior change

@Loirooriol Loirooriol added A-layout/2020 https://github.com/servo/servo/wiki/Layout-2020 T-linux-wpt Do a try run of the WPT labels Nov 21, 2025
@github-actions github-actions bot removed the T-linux-wpt Do a try run of the WPT label Nov 21, 2025
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github-actions bot commented Nov 21, 2025

🔨 Triggering try run (#19577893378) for Linux (WPT)

@Loirooriol Loirooriol force-pushed the preserve-layout_caches branch from f19c7aa to 2937882 Compare November 21, 2025 17:35
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Test results for linux-wpt from try job (#19577893378):

Flaky unexpected result (42)
  • TIMEOUT /FileAPI/url/url-in-tags-revoke.window.html (#19978)
    • TIMEOUT [expected PASS] subtest: Fetching a blob URL immediately before revoking it works in <script> tags.

      Test timed out

  • OK /IndexedDB/idbfactory_open.any.html
    • FAIL [expected PASS] subtest: Calling open() with version argument 1.5 should not throw.

      assert_equals: version expected 1 but got 9007199254740991

  • OK /_mozilla/mozilla/getBoundingClientRect.html (#39668)
    • FAIL [expected PASS] subtest: getBoundingClientRect 1

      assert_equals: expected 62 but got 60.35

  • OK /_mozilla/webxr/create_session.https.html
    • FAIL [expected PASS] subtest: create_session

      can't access property "simulateDeviceConnection", navigator.xr.test is undefined

  • OK /_mozilla/webxr/obtain_frame.https.html
    • FAIL [expected PASS] subtest: obtain_frame

      promise_test: Unhandled rejection with value: object "TypeError: can't access property "simulateDeviceConnection", navigator.xr.test is undefined"

  • ERROR [expected TIMEOUT] /_mozilla/webxr/sessionavailable.https.html
  • CRASH [expected OK] /_webgl/conformance2/wasm/readpixels-2gb-in-4gb-wasm-memory.html
  • OK /content-security-policy/frame-ancestors/frame-ancestors-path-ignored.window.html (#36468)
    • FAIL [expected PASS] subtest: A 'frame-ancestors' CSP directive with a URL that includes a path should be ignored.

      assert_unreached: The IFrame should have been blocked (or cross-origin). It wasn't. Reached unreachable code

  • TIMEOUT /content-security-policy/inheritance/location-reload.html (#38983)
    • PASS [expected FAIL] subtest: location.reload() of empty iframe.
  • OK /css/css-cascade/layer-cssom-order-reverse.html (#36094)
    • PASS [expected FAIL] subtest: Delete layer invalidates @font-face
  • OK /css/css-cascade/layer-font-face-override.html (#35935)
    • PASS [expected FAIL] subtest: @font-face override update with appended sheet 1
    • PASS [expected FAIL] subtest: @font-face override update with appended sheet 2
  • OK /css/css-ui/text-overflow-023.html (#19861)
    • FAIL [expected PASS] subtest: Checks hit testing on the ellipsis

      assert_equals: the element targeted by a hit on the ellipsis is the elided inline. expected "target" but got "parent"

  • OK /custom-elements/form-associated/ElementInternals-setFormValue.html (#29174)
    • PASS [expected FAIL] subtest: Single value - Non-empty name exists
  • TIMEOUT [expected FAIL] /dom/xslt/large-cdata.html (#38029)
  • CRASH [expected ERROR] /encoding/streams/decode-bad-chunks.any.serviceworker.html
  • TIMEOUT [expected OK] /fetch/api/redirect/redirect-keepalive.https.any.html (#32153)
    • TIMEOUT [expected PASS] subtest: [keepalive][iframe][load] mixed content redirect; setting up

      Test timed out

  • CRASH [expected ERROR] /fetch/api/request/request-cache-default-conditional.any.serviceworker.html
  • CRASH [expected OK] /fetch/fetch-later/permissions-policy/deferred-fetch-allowed-by-permissions-policy-attribute-redirect.https.window.html
  • CRASH [expected ERROR] /fetch/http-cache/304-update.any.serviceworker.html
  • OK [expected CRASH] /fetch/metadata/generated/element-iframe.https.sub.html (#40341)
  • CRASH [expected OK] /gamepad/idlharness-extensions.https.window.html
  • OK /html/browsers/history/the-history-interface/traverse_the_history_3.html (#21383)
    • PASS [expected FAIL] subtest: Multiple history traversals, last would be aborted
  • CRASH [expected OK] /html/browsers/origin/origin-keyed-agent-clusters/getter-special-cases/sandboxed-iframe-no.https.html
  • CRASH [expected OK] /html/browsers/origin/origin-keyed-agent-clusters/regression-1399759.https.sub.html?pipe=header(Origin-Agent-Cluster,%3F0)
  • CRASH [expected OK] /html/capability-delegation/delegate-fullscreen-request-popup-same-origin.https.tentative.html
  • CRASH [expected TIMEOUT] /html/capability-delegation/delegation-consumes-activation.https.tentative.html
  • CRASH [expected OK] /html/dom/documents/dom-tree-accessors/nameditem-03.html
  • OK /html/semantics/document-metadata/the-meta-element/pragma-directives/attr-meta-http-equiv-refresh/allow-scripts-flag-changing-1.html (#39694)
    • PASS [expected FAIL] subtest: Meta refresh is blocked by the allow-scripts sandbox flag at its creation time, not when refresh comes due
  • OK [expected TIMEOUT] /html/semantics/embedded-content/media-elements/src_object_blob.html (#40340)
    • PASS [expected TIMEOUT] subtest: HTMLMediaElement.srcObject blob
  • OK /html/semantics/embedded-content/the-iframe-element/iframe-loading-lazy-nav-location-replace-set-src.html (#32697)
    • PASS [expected FAIL] subtest: Navigating iframe loading='lazy' and then setting src: location.replace
  • OK /html/semantics/forms/form-submission-0/jsurl-form-submit.tentative.html (#36489)
    • PASS [expected FAIL] subtest: Verifies that form submissions scheduled inside javascript: urls take precedence over the javascript: url's return value.
  • OK /html/semantics/forms/form-submission-0/text-plain.window.html (#28687)
    • FAIL [expected PASS] subtest: text/plain: Basic test (formdata event)

      assert_equals: expected "basic=test\r\n" but got ""

    • FAIL [expected PASS] subtest: text/plain: Basic File test (normal form)

      assert_equals: expected "basic=file-test.txt\r\n" but got ""

    • PASS [expected FAIL] subtest: text/plain: 0x00 in name (formdata event)
    • PASS [expected FAIL] subtest: text/plain: 0x00 in filename (normal form)
    • PASS [expected FAIL] subtest: text/plain: \r\n in name (normal form)
  • OK /html/semantics/forms/form-submission-0/urlencoded2.window.html (#28687)
    • FAIL [expected PASS] subtest: application/x-www-form-urlencoded: Basic test (formdata event)

      assert_equals: expected "basic=test" but got ""

    • FAIL [expected PASS] subtest: application/x-www-form-urlencoded: Basic File test (normal form)

      assert_equals: expected "basic=file-test.txt" but got ""

    • PASS [expected FAIL] subtest: application/x-www-form-urlencoded: Basic File test (formdata event)
    • PASS [expected FAIL] subtest: application/x-www-form-urlencoded: 0x00 in value (formdata event)
  • ERROR [expected TIMEOUT] /html/semantics/forms/form-submission-target/rel-base-target.html (#40379)
  • OK [expected CRASH] /html/semantics/forms/the-fieldset-element/disabled-003.html (#31730, #39631)
  • CRASH [expected ERROR] /html/semantics/scripting-1/the-script-element/module/import-meta/import-meta-resolve.any.serviceworker-module.html
  • OK [expected ERROR] /html/user-activation/no-activation-thru-escape-key.html (#40343)
  • OK /html/webappapis/user-prompts/print-during-unload.html (#35944)
    • FAIL [expected PASS] subtest: print() during unload

      assert_array_equals: expected property 1 to be "destination" but got "error: window.print is not a function" (expected array ["start", "destination"] got ["start", "error: window.print is not a function"])

  • CRASH [expected OK] /trusted-types/get-trusted-types-compliant-attribute-value.html
  • TIMEOUT /trusted-types/trusted-types-navigation.html?31-35 (#38034)
    • TIMEOUT [expected PASS] subtest: Navigate a frame via form-submission with javascript:-urls in report-only mode.

      Test timed out

    • NOTRUN [expected TIMEOUT] subtest: Navigate a frame via form-submission with javascript:-urls w/ default policy in report-only mode.
  • CRASH [expected TIMEOUT] /wasm/webapi/empty-body.any.worker.html
  • CRASH [expected OK] /wasm/webapi/esm-integration/wasm-to-wasm-link-error.tentative.html
Stable unexpected results that are known to be intermittent (29)
  • OK /IndexedDB/idbobjectstore_getAll.any.html (#39276)
    • PASS [expected FAIL] subtest: Get all values with transaction.commit()
  • OK /IndexedDB/idbobjectstore_getAll.any.worker.html (#39400)
    • PASS [expected FAIL] subtest: Get all values with transaction.commit()
  • FAIL [expected PASS] /_mozilla/mozilla/sslfail.html (#10760)
  • TIMEOUT [expected OK] /_mozilla/mozilla/window_resize_event.html (#36741)
    • TIMEOUT [expected PASS] subtest: Popup onresize event fires after resizeTo

      Test timed out

  • OK /_webgl/conformance/textures/misc/texture-upload-size.html (#21770)
    • PASS [expected FAIL] subtest: WebGL test #45
    • PASS [expected FAIL] subtest: WebGL test #47
    • PASS [expected FAIL] subtest: WebGL test #49
    • PASS [expected FAIL] subtest: WebGL test #51
    • FAIL [expected PASS] subtest: WebGL test #53

      assert_true: Texture was smaller than the expected size 2x2 expected true got false

    • FAIL [expected PASS] subtest: WebGL test #55

      assert_true: getError expected: INVALID_VALUE. Was NO_ERROR : when calling texSubImage2D with the same texture upload with offset 1, 1 expected true got false

    • FAIL [expected PASS] subtest: WebGL test #57

      assert_true: Texture was smaller than the expected size 2x2 expected true got false

    • FAIL [expected PASS] subtest: WebGL test #59

      assert_true: getError expected: INVALID_VALUE. Was NO_ERROR : when calling texSubImage2D with the same texture upload with offset 1, 1 expected true got false

    • PASS [expected FAIL] subtest: WebGL test #61
    • PASS [expected FAIL] subtest: WebGL test #63
    • And 10 more unexpected results...
  • OK /css/css-fonts/generic-family-keywords-001.html (#37467)
    • PASS [expected FAIL] subtest: @font-face matching for quoted and unquoted generic(kai)
    • FAIL [expected PASS] subtest: @font-face matching for quoted and unquoted generic(khmer-mul)

      assert_equals: quoted generic(khmer-mul) matches  @font-face rule expected 50 but got 30

  • OK /css/css-fonts/generic-family-keywords-003.html (#38994)
    • PASS [expected FAIL] subtest: @font-face matching for quoted and unquoted generic(nastaliq) (drawing text in a canvas)
    • PASS [expected FAIL] subtest: @font-face matching for quoted and unquoted ui-monospace (drawing text in a canvas)
  • OK /fetch/api/credentials/cookies.any.html (#40672)
    • FAIL [expected PASS] subtest: Include mode: 1 cookie

      assert_equals: Request include cookie(s) expected "a=1" but got "a=1; domain-attribute-matches-host=0"

    • FAIL [expected PASS] subtest: Include mode: 2 cookies

      assert_equals: Request include cookie(s) expected "b=2; c=3" but got "b=2; c=3; domain-attribute-matches-host=0"

    • FAIL [expected PASS] subtest: Omit mode: no cookie is stored

      assert_false: Request does not have cookie(s) expected false got true

    • FAIL [expected PASS] subtest: Same-origin mode: 1 cookie

      assert_equals: Request include cookie(s) expected "a=1" but got "a=1; domain-attribute-matches-host=0"

    • FAIL [expected PASS] subtest: Same-origin mode: 2 cookies

      assert_equals: Request include cookie(s) expected "b=2; c=3" but got "b=2; c=3; domain-attribute-matches-host=0"

  • OK /fetch/fetch-later/permissions-policy/deferred-fetch-allowed-by-permissions-policy.https.window.html (#40478)
    • FAIL [expected PASS] subtest: Permissions policy header: "deferred-fetch=*" allows fetchLater() in the top-level document.

      assert_equals: Number of sent beacons does not match expected count: expected 1 but got 0

  • OK /fetch/metadata/generated/css-font-face.https.sub.tentative.html (#32732)
    • PASS [expected FAIL] subtest: sec-fetch-dest
  • OK /fetch/metadata/generated/css-font-face.sub.tentative.html (#34624)
    • PASS [expected FAIL] subtest: sec-fetch-storage-access - Not sent to non-trustworthy same-site destination
    • FAIL [expected PASS] subtest: sec-fetch-storage-access - Not sent to non-trustworthy cross-site destination

      promise_test: Unhandled rejection with value: object "Error: Failed to query for recorded headers."

  • OK /fetch/metadata/generated/element-img-environment-change.https.sub.html (#30111)
    • PASS [expected FAIL] subtest: sec-fetch-site - Cross-site, no attributes
    • FAIL [expected PASS] subtest: sec-fetch-site - Cross-Site -> Same-Site, no attributes

      promise_test: Unhandled rejection with value: object "Error: Failed to query for recorded headers."

    • PASS [expected FAIL] subtest: sec-fetch-site - Cross-Site -> Cross-Site, no attributes
    • FAIL [expected PASS] subtest: sec-fetch-site - Same-Origin -> Same Origin, no attributes

      promise_test: Unhandled rejection with value: object "Error: Failed to query for recorded headers."

    • PASS [expected FAIL] subtest: sec-fetch-site - Same-Origin -> Same-Site, no attributes
    • FAIL [expected PASS] subtest: sec-fetch-site - Same-Origin -> Cross-Site, no attributes

      promise_test: Unhandled rejection with value: object "Error: Failed to query for recorded headers."

    • PASS [expected FAIL] subtest: sec-fetch-site - Same-Site -> Same Origin, no attributes
    • FAIL [expected PASS] subtest: sec-fetch-site - Same-Site -> Same-Site, no attributes

      promise_test: Unhandled rejection with value: object "Error: Failed to query for recorded headers."

    • PASS [expected FAIL] subtest: sec-fetch-site - Same-Site -> Cross-Site, no attributes
    • PASS [expected FAIL] subtest: sec-fetch-user - no attributes
    • And 1 more unexpected results...
  • OK /fetch/metadata/generated/element-img-environment-change.sub.html (#30111)
    • PASS [expected FAIL] subtest: sec-fetch-mode - Not sent to non-trustworthy same-origin destination, no attributes
    • PASS [expected FAIL] subtest: sec-fetch-user - Not sent to non-trustworthy cross-site destination, no attributes
    • PASS [expected FAIL] subtest: sec-fetch-storage-access - Not sent to non-trustworthy same-origin destination, no attributes
    • FAIL [expected PASS] subtest: sec-fetch-site - HTTPS downgrade-upgrade, no attributes

      promise_test: Unhandled rejection with value: object "Error: Failed to query for recorded headers."

  • ERROR /fetch/metadata/generated/serviceworker.https.sub.html (#36247)
    • FAIL [expected PASS] subtest: sec-fetch-site - Same origin, no options - registration

      promise_test: Unhandled rejection with value: object "Error: Failed to query for recorded headers."

  • OK [expected ERROR] /focus/focus-event-after-switching-iframes.sub.html (#40368)
  • CRASH [expected OK] /html/browsers/browsing-the-web/navigating-across-documents/005.html (#27062)
  • OK /html/browsers/browsing-the-web/navigating-across-documents/navigation-unload-same-origin-fragment.html (#20768)
    • FAIL [expected PASS] subtest: Tests that a fragment navigation in the unload handler will not block the initial navigation

      assert_equals: expected "" but got "#fragment"

  • OK /html/browsers/browsing-the-web/navigating-across-documents/refresh/same-document-refresh.html (#34597)
    • FAIL [expected PASS] subtest: Same-Document Referrer from Refresh

      assert_equals: original page loads expected "http://web-platform.test:8000/html/browsers/browsing-the-web/navigating-across-documents/refresh/resources/refresh-with-section.sub.html?url=%23section" but got "http://web-platform.test:8000/html/browsers/browsing-the-web/navigating-across-documents/refresh/resources/refresh-with-section.sub.html?url=%23section#section"

  • OK /html/browsers/browsing-the-web/navigating-across-documents/replace-before-load/a-click.html (#28697)
    • PASS [expected FAIL] subtest: aElement.click() before the load event must NOT replace
  • OK /html/browsers/history/the-history-interface/traverse_the_history_4.html (#21383)
    • PASS [expected FAIL] subtest: Multiple history traversals, last would be aborted
  • OK /html/dom/documents/resource-metadata-management/document-cookie.html (#40673)
    • FAIL [expected PASS] subtest: document has no cookie

      assert_equals: expected "" but got "domain-attribute-matches-host=0"

    • FAIL [expected PASS] subtest: document.cookie

      assert_equals: expected "" but got "domain-attribute-matches-host=0"

    • FAIL [expected PASS] subtest: document.cookie 1

      assert_equals: expected "a=b" but got "a=b; domain-attribute-matches-host=0"

    • FAIL [expected PASS] subtest: document.cookie 2

      assert_equals: expected "" but got "a=b; domain-attribute-matches-host=0"

  • ERROR [expected OK] /html/infrastructure/common-dom-interfaces/collections/domstringlist.html (#40665)
  • ERROR [expected OK] /html/semantics/embedded-content/media-elements/event_timeupdate_noautoplay.html (#25046)
  • OK [expected CRASH] /html/semantics/embedded-content/media-elements/preserves-pitch.html (#40352)
    • FAIL [expected PASS] subtest: Test that preservesPitch is present and unprefixed.

      assert_true: expected true got false

    • FAIL [expected PASS] subtest: Test that preservesPitch is on by default

      assert_true: expected true got undefined

    • FAIL [expected PASS] subtest: Speed-ups should change the pitch when preservesPitch=false

      assert_approx_equals: The actual pitch should be close to the expected pitch. expected 880 +/- 132 but got 431.0850439882698

    • FAIL [expected PASS] subtest: Slow-downs should change the pitch when preservesPitch=false

      assert_approx_equals: The actual pitch should be close to the expected pitch. expected 220 +/- 33 but got 431.0850439882698

  • CRASH [expected OK] /pointerevents/compat/pointerevent_touch-action_two-finger_interaction.html (#40418)
  • OK /preload/preload-error.sub.html (#37177)
    • PASS [expected FAIL] subtest: 404 (fetch): main
    • PASS [expected FAIL] subtest: CORS (fetch): main
  • TIMEOUT /resource-timing/test_resource_timing.html (#25720)
    • PASS [expected FAIL] subtest: PerformanceEntry has correct name, initiatorType, startTime, and duration (img)
  • TIMEOUT [expected OK] /trusted-types/trusted-types-navigation.html?26-30 (#38807)
    • PASS [expected FAIL] subtest: Navigate a window via form-submission with javascript:-urls in report-only mode.
    • PASS [expected FAIL] subtest: Navigate a frame via form-submission with javascript:-urls in enforcing mode.
    • TIMEOUT [expected PASS] subtest: Navigate a frame via form-submission with javascript:-urls w/ default policy in enforcing mode.

      Test timed out

  • OK [expected ERROR] /webxr/render_state_update.https.html (#27535)

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✨ Try run (#19577893378) succeeded.

@Loirooriol Loirooriol marked this pull request as ready for review November 21, 2025 17:38
@servo-highfive servo-highfive added the S-awaiting-review There is new code that needs to be reviewed. label Nov 21, 2025
@TimvdLippe TimvdLippe added this pull request to the merge queue Nov 21, 2025
@servo-highfive servo-highfive added the S-awaiting-merge The PR is in the process of compiling and running tests on the automated CI. label Nov 21, 2025
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Loirooriol commented Nov 21, 2025

Need to rebase after #40795 lands

imatge

@Loirooriol Loirooriol removed this pull request from the merge queue due to a manual request Nov 21, 2025
@servo-highfive servo-highfive removed the S-awaiting-merge The PR is in the process of compiling and running tests on the automated CI. label Nov 21, 2025
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TimvdLippe commented Nov 21, 2025

Ah sorry, didn't know. Thought that Martin forgot to add it to the merge queue.

@Loirooriol @mrobinson
layout: Preserve cached layout results of undamaged descendants
7767047 
Co-authored-by: Martin Robinson <mrobinson@igalia.com>
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
@Loirooriol Loirooriol force-pushed the preserve-layout_caches branch from 2937882 to 7767047 Compare November 21, 2025 19:24
@Loirooriol Loirooriol enabled auto-merge November 21, 2025 19:24
@Loirooriol Loirooriol added this pull request to the merge queue Nov 21, 2025
@servo-highfive servo-highfive added the S-awaiting-merge The PR is in the process of compiling and running tests on the automated CI. label Nov 21, 2025
@github-merge-queue github-merge-queue bot removed this pull request from the merge queue due to failed status checks Nov 21, 2025
@servo-highfive servo-highfive added S-tests-failed The changes caused existing tests to fail. and removed S-awaiting-merge The PR is in the process of compiling and running tests on the automated CI. labels Nov 21, 2025
@simonwuelker simonwuelker added this pull request to the merge queue Nov 21, 2025
@servo-highfive servo-highfive added S-awaiting-merge The PR is in the process of compiling and running tests on the automated CI. and removed S-tests-failed The changes caused existing tests to fail. labels Nov 21, 2025
Merged via the queue into servo:main with commit 44876dd Nov 21, 2025
38 checks passed
@servo-highfive servo-highfive removed the S-awaiting-merge The PR is in the process of compiling and running tests on the automated CI. label Nov 21, 2025
@Loirooriol Loirooriol deleted the preserve-layout_caches branch November 21, 2025 20:56
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