Speculative load measurement API - preload tracking [chromium/src : main]

[Yoav Weiss (@Shopify) (Gerrit)]

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[Kouhei Ueno (Gerrit)]

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Kouhei Ueno added 1 comment

File third_party/blink/renderer/platform/loader/fetch/resource_fetcher.cc

Line 1987, Patchset 2 (Latest): KURL url = resource->Url();

Kouhei Ueno . unresolved

const KURL&

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[Yoav Weiss (@Shopify) (Gerrit)]

Attention needed from Hiroshige Hayashizaki and Kouhei Ueno

Yoav Weiss (@Shopify) added 1 comment

File third_party/blink/renderer/platform/loader/fetch/resource_fetcher.cc

Line 1987, Patchset 2: KURL url = resource->Url();

Kouhei Ueno . resolved

const KURL&

Yoav Weiss (@Shopify)

Done

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[Kouhei Ueno (Gerrit)]

Attention needed from Hiroshige Hayashizaki and Yoav Weiss (@Shopify)

Kouhei Ueno added 1 comment

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/pagehide-speculations-preload.tentative.html

Line 74, Patchset 3 (Latest): await new Promise(resolve => setTimeout(resolve, 200));

Kouhei Ueno . unresolved

To avoid flaky test, would you make the resource be served via custom handler so we can ensure server received the request?

Something similar to
third_party/blink/web_tests/external/wpt/speculation-rules/prefetch/resources/prefetch.py to put data on server stash and we continuously fetch the stash until it says the server has received the req.

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[Yoav Weiss (@Shopify) (Gerrit)]

Attention needed from Hiroshige Hayashizaki and Kouhei Ueno

Yoav Weiss (@Shopify) added 1 comment

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/pagehide-speculations-preload.tentative.html

Line 74, Patchset 3: await new Promise(resolve => setTimeout(resolve, 200));

Kouhei Ueno . resolved

To avoid flaky test, would you make the resource be served via custom handler so we can ensure server received the request?

Something similar to
third_party/blink/web_tests/external/wpt/speculation-rules/prefetch/resources/prefetch.py to put data on server stash and we continuously fetch the stash until it says the server has received the req.

Yoav Weiss (@Shopify)

Done

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[Kouhei Ueno (Gerrit)]

Attention needed from Hiroshige Hayashizaki and Yoav Weiss (@Shopify)

Kouhei Ueno added 14 comments

File third_party/blink/renderer/core/events/page_transition_event.h

Line 73, Patchset 5 (Latest): protected:

Kouhei Ueno . unresolved

Would you elaborate on why this needs change?

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/pagehide-speculations-preload.tentative.html

Line 74, Patchset 3: await new Promise(resolve => setTimeout(resolve, 200));

Kouhei Ueno . resolved

To avoid flaky test, would you make the resource be served via custom handler so we can ensure server received the request?

Something similar to
third_party/blink/web_tests/external/wpt/speculation-rules/prefetch/resources/prefetch.py to put data on server stash and we continuously fetch the stash until it says the server has received the req.

Yoav Weiss (@Shopify)

Done

Kouhei Ueno

Sorry I should have asked if we really need this first.
if we are waiting on onload, would it be enough?

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/pagehide-speculations-preload.tentative.https.html

Line 64, Patchset 5 (Latest): assert_true(result.speculations !== null && result.speculations !== undefined,

Kouhei Ueno . unresolved

nit: split to two assert_not_equals

Line 69, Patchset 5 (Latest): const preloads = result.speculations.preloads;

Kouhei Ueno . unresolved

should we check its contents?

Line 90, Patchset 5 (Latest): await waitForPreloadRequest(uuid);

Kouhei Ueno . unresolved

ditto

Line 109, Patchset 5 (Latest): const preloads = result.speculations.preloads;

Kouhei Ueno . unresolved

Can we match `preloads` exactly against expected array?
I believe we expect it to have the precise set of elements.

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/pagehide-speculations-used-preload.tentative.html

Line 99, Patchset 5 (Latest): assert_true(result.speculations !== null,

Kouhei Ueno . unresolved

assert_not_equals

Line 107, Patchset 5 (Latest): assert_true(unusedPreload !== undefined,

Kouhei Ueno . unresolved

assert_not_equals

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/support/page-with-multiple-preloads.html

Line 1, Patchset 5 (Latest):<!DOCTYPE html>

Kouhei Ueno . unresolved

Is this file used?

Line 5, Patchset 5 (Latest):<link rel="preload" href="unused-script.js" as="script">

Kouhei Ueno . unresolved

nonexistent?

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/support/page-with-pagehide-reporter.html

Line 9, Patchset 5 (Latest): type: 'pagehide',

Kouhei Ueno . unresolved

Would you elaborate why we need to pass this value?

Line 15, Patchset 5 (Latest): persisted: event.persisted

Kouhei Ueno . unresolved

Would you elaborate why we need to pass this value?

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/support/page-with-unused-preload.html

Line 1, Patchset 5 (Latest):<!DOCTYPE html>

Kouhei Ueno . unresolved

Is this file used?

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/support/page-with-used-preload-and-reporter.html

Line 9, Patchset 5 (Latest): if (parent && parent !== window && parent.pagehideCallback) {

Kouhei Ueno . unresolved

what is `parent !== window` condition needed for?

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[Yoav Weiss (@Shopify) (Gerrit)]

Attention needed from Hiroshige Hayashizaki and Kouhei Ueno

Yoav Weiss (@Shopify) added 10 comments

File third_party/blink/renderer/core/events/page_transition_event.h

Line 73, Patchset 5: protected:

Kouhei Ueno . resolved

Would you elaborate on why this needs change?

Yoav Weiss (@Shopify)

It doesn't. Removed

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/pagehide-speculations-preload.tentative.https.html

Line 64, Patchset 5: assert_true(result.speculations !== null && result.speculations !== undefined,

Kouhei Ueno . resolved

nit: split to two assert_not_equals

Yoav Weiss (@Shopify)

Done

Line 69, Patchset 5: const preloads = result.speculations.preloads;

Kouhei Ueno . resolved

should we check its contents?

Yoav Weiss (@Shopify)

Sure, but it's empty in this test

Line 109, Patchset 5: const preloads = result.speculations.preloads;

Kouhei Ueno . resolved

Can we match `preloads` exactly against expected array?
I believe we expect it to have the precise set of elements.

Yoav Weiss (@Shopify)

Done

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/pagehide-speculations-used-preload.tentative.html

Line 99, Patchset 5: assert_true(result.speculations !== null,

Kouhei Ueno . resolved

assert_not_equals

Yoav Weiss (@Shopify)

Done

Line 107, Patchset 5: assert_true(unusedPreload !== undefined,

Kouhei Ueno . resolved

assert_not_equals

Yoav Weiss (@Shopify)

Done

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/support/page-with-pagehide-reporter.html

Line 9, Patchset 5: type: 'pagehide',

Kouhei Ueno . resolved

Would you elaborate why we need to pass this value?

Yoav Weiss (@Shopify)

We don't. removed!

Line 15, Patchset 5: persisted: event.persisted

Kouhei Ueno . resolved

Would you elaborate why we need to pass this value?

Yoav Weiss (@Shopify)

We don't. Removed!

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/support/page-with-unused-preload.html

Line 1, Patchset 5:<!DOCTYPE html>

Kouhei Ueno . resolved

Is this file used?

Yoav Weiss (@Shopify)

No, removed!

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/support/page-with-used-preload-and-reporter.html

Line 9, Patchset 5: if (parent && parent !== window && parent.pagehideCallback) {

Kouhei Ueno . resolved

what is `parent !== window` condition needed for?

Yoav Weiss (@Shopify)

To only report when loaded in an iframe. But I guess it's not strictly needed, so removed.

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[Yoav Weiss (@Shopify) (Gerrit)]

Attention needed from Hiroshige Hayashizaki and Kouhei Ueno

Yoav Weiss (@Shopify) added 2 comments

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/support/page-with-multiple-preloads.html

Line 1, Patchset 5:<!DOCTYPE html>

Kouhei Ueno . resolved

Is this file used?

Yoav Weiss (@Shopify)

Nope. Removed.

Line 5, Patchset 5:<link rel="preload" href="unused-script.js" as="script">

Kouhei Ueno . resolved

nonexistent?

Yoav Weiss (@Shopify)

Removed the file

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[Yoav Weiss (@Shopify) (Gerrit)]

Attention needed from Hiroshige Hayashizaki and Kouhei Ueno

Yoav Weiss (@Shopify) added 1 comment

File third_party/blink/web_tests/external/wpt/html/browsers/browsing-the-web/unloading-documents/pagehide-speculations-preload.tentative.https.html

Line 90, Patchset 5: await waitForPreloadRequest(uuid);

Kouhei Ueno . unresolved

ditto

Yoav Weiss (@Shopify)

Can you elaborate what you meant here?

Gerrit-Comment-Date: Fri, 13 Mar 2026 05:01:29 +0000