iframe-proxy

lubieowoce · 2026-09-04T21:45:15Z

if a page didn't use runtime data during build but started doing so after the revalidation (i.e. the hints say its statically-prefetchable but now it's not), we're supposed to be doing a follow-up runtime request based on the needsRuntimeRequest promise, but this was not actually happening.

the bug goes as follows:

if we get an entry from a static prefetch, but needsRuntimeRequest is true, we save it as PPR (or StaticShell if it's a shell rewound from the static response). otherwise, we'd have saved it as PPRRuntime (or RuntimeShell for shells) to indicate that it satisfies those requests.
wouldRuntimeRequestProvideMore compares the runtime strategy for the current static walk to the entry's strategy to check if it should do a runtime request. this boils down to a comparison of RuntimeShell > PPR for a shell request
however, in the FetchStrategy enum, RuntimeShell = 3 and PPR = 3, so RuntimeShell > PPR is false, which makes wouldRuntimeRequestProvideMore return false. so, if we have a PPR entry, we'll never do a follow-up runtime shell request.

this is fixed by swapping the two values in the enum.
this is a bit of a lie, because there is no single correct ordering -- a PPR entry might actually provide more content than a ShellRuntime entry if the route uses static params.
however, if we end up with PPR but its needsRuntimeRequest was true due to runtime data, that indicates that we should've done a runtime request in the first place, we just didn't know we should do so because the prefetch hint was stale, so the new ordering achieves the correct behavior in this case.

Edge cases

there is one (somewhat involved) edge case to this that i know of.
if the post-revalidation static response has:

a shell that didn't access runtime data (i.e. needsRuntimeRequest = false in the shell stage)
a prefetch that did access runtime data (i.e. needsRuntimeRequest = true in the static stage)

then we'll:

write the shell as ShellRuntime (because needsRuntimeRequest = false, and a runtime shell would not in fact provide more data)
write the prefetch as PPR (and not PPRRuntime, because needsRuntimeRequest = true, and a runtime prefetch would provide more data)

with the new ordering, this means we'll end up preferring the ShellRuntime entry over the PPR entry even though the shell is a strict subset of it and would be missing static params and content gated behind prefetch() or navigation().

this can be observed as follows:

when a <Link prefetch={true}> to such a page is revealed, we won't request a runtime shell (due to already having a ShellRuntime entry), but we will request a runtime prefetch (because PPR is not enough). so far this is correct
if the navigation happens before this runtime prefetch completes, we will display what we have. but we'll prefer the rewound ShellRuntime shell entry over than the PPR entry it originated from because of the enum ordering. so we may end up not showing content despite having it in the cache

i'm not sure how to resolve this yet, but i think the current recordedFetchStrategy trick can't handle this, and we need a more involved mechanism that can detect when the PPR entry is actually better. i don't consider this a blocker for this fix though

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github-actions · 2026-09-04T21:45:39Z

Failing test suites

Commit: f31bfbe | About building and testing Next.js

pnpm test-start-experimental-turbo test/e2e/app-dir/segment-cache/prefetch-scheduling/prefetch-scheduling.test.ts (turbopack) (Experimental) (job)

segment cache prefetch scheduling > increases the priority of a viewport-initiated prefetch on hover (DD)
segment cache prefetch scheduling > reserve special bandwidth for the most recently hovered link (DD)
segment cache prefetch scheduling > reschedules a link's prefetch when it re-enters the viewport (DD)

Expand output

● segment cache prefetch scheduling › increases the priority of a viewport-initiated prefetch on hover

Expected sequence of responses does not match:

- Expected
+ Received

  Array [
    "Content of page 2",
    "Content of page 6",
-   "Content of page 4",
  ]

NOTE: Assertions are checked in order, so if an expectation is missing, it may have actually appeared earlier in the sequence than expected. Make sure the order is correct.

  21 |
  22 |     const checkbox = await browser.elementByCss('input[type="checkbox"]')
> 23 |     await act(
     |           ^
  24 |       async () => {
  25 |         // Reveal the links to start prefetching, but block the responses from
  26 |         // reaching the client. This will initiate prefetches for the route

  at Object.act (e2e/app-dir/segment-cache/prefetch-scheduling/prefetch-scheduling.test.ts:23:11)

● segment cache prefetch scheduling › reserve special bandwidth for the most recently hovered link

Expected sequence of responses does not match:

- Expected
+ Received

- Array [
-   "Content of page 6",
-   "Content of page 8",
-   "Content of page 5",
- ]
+ Array []

NOTE: Assertions are checked in order, so if an expectation is missing, it may have actually appeared earlier in the sequence than expected. Make sure the order is correct.

  142 |
  143 |     const checkbox = await browser.elementByCss('input[type="checkbox"]')
> 144 |     await act(async () => {
      |           ^
  145 |       // Reveal the links to start prefetching, but block the responses from
  146 |       // reaching the client. This will initiate prefetches for the route
  147 |       // trees, but it won't start prefetching any segment data yet until the

  at Object.act (e2e/app-dir/segment-cache/prefetch-scheduling/prefetch-scheduling.test.ts:144:11)

● segment cache prefetch scheduling › reschedules a link's prefetch when it re-enters the viewport

Expected a response containing the given string:

Content of page 5

  282 |     // Now we'll reveal the links again to verify that the prefetch tasks are
  283 |     // rescheduled, after having been canceled.
> 284 |     await act(
      |           ^
  285 |       async () => {
  286 |         await checkbox.click()
  287 |       },

  at Object.act (e2e/app-dir/segment-cache/prefetch-scheduling/prefetch-scheduling.test.ts:284:11)

pnpm test-start-experimental-turbo test/e2e/app-dir/segment-cache/search-params/segment-cache-search-params.test.ts (turbopack) (Experimental) (job)

segment cache (search params) > when fetching without PPR (e.g. prefetch="unstable_forceStale"), includes the search params in the cache key (DD)

Expand output

● segment cache (search params) › when fetching without PPR (e.g. prefetch="unstable_forceStale"), includes the search params in the cache key

Expected a response containing the given string:

target-page-with-search-param

   98 |       'input[data-link-accordion="/search-params/target-page?searchParam=a_PPR"]'
   99 |     )
> 100 |     await act(
      |           ^
  101 |       async () => {
  102 |         await revealA.click()
  103 |       },

  at Object.act (e2e/app-dir/segment-cache/search-params/segment-cache-search-params.test.ts:100:11)

pnpm test-start-experimental-turbo test/e2e/app-dir/segment-cache/vary-params/vary-params.test.ts (turbopack) (Experimental) (job)

segment cache - vary params > tracks param access in generateMetadata (DD)
segment cache - vary params > reuses page segment when layout varies but page does not (DD)

Expand output

● segment cache - vary params › tracks param access in generateMetadata

Timed out waiting for a request to be initiated.

  358 |     // Second prefetch: head re-fetched (metadata varies on slug),
  359 |     // but body is cached (body doesn't access slug)
> 360 |     await act(async () => {
      |           ^
  361 |       const toggle = await browser.elementByCss(
  362 |         'input[data-link-accordion="/metadata/bbb"]'
  363 |       )

  at Object.act (e2e/app-dir/segment-cache/vary-params/vary-params.test.ts:360:11)

● segment cache - vary params › reuses page segment when layout varies but page does not

Timed out waiting for a request to be initiated.

  423 |     // Second prefetch: layout re-fetched (varies on item),
  424 |     // page is cached (only varies on category)
> 425 |     await act(async () => {
      |           ^
  426 |       const toggle = await browser.elementByCss(
  427 |         'input[data-link-accordion="/page-reuse/electronics/tablet"]'
  428 |       )

  at Object.act (e2e/app-dir/segment-cache/vary-params/vary-params.test.ts:425:11)

pnpm test-dev test/development/app-dir/instant-navs-devtools/instant-navs-devtools.test.ts (job)

instant-nav-panel > transitions between capture types > should avoid showing stale SPA state when reloading from a captured SPA state into captured MPA state (DD)

Expand output

● instant-nav-panel › transitions between capture types › should avoid showing stale SPA state when reloading from a captured SPA state into captured MPA state

expect(received).toContain(expected) // indexOf

Expected substring: "/target-page/my-post"
Received string:    "http://localhost:42071/"

  809 |       // capture an MPA load of the wrong route.
  810 |       await retry(async () => {
> 811 |         expect(await browser.url()).toContain('/target-page/my-post')
      |                                     ^
  812 |       }, 10000)
  813 |
  814 |       await browser.refresh()

  at toContain (development/app-dir/instant-navs-devtools/instant-navs-devtools.test.ts:811:37)
  at retry (lib/next-test-utils.ts:871:14)
  at Object.<anonymous> (development/app-dir/instant-navs-devtools/instant-navs-devtools.test.ts:810:7)

pnpm test-start test/e2e/app-dir/segment-cache/memory-pressure/segment-cache-memory-pressure.test.ts (job)

segment cache memory pressure > evicts least recently used prefetch data once cache size exceeds limit (DD)
segment cache memory pressure > does not leak memory when repeatedly triggering prefetches (DD)

Expand output

● segment cache memory pressure › evicts least recently used prefetch data once cache size exceeds limit

Timed out waiting for a request to be initiated.

  37 |     // Switching to tab 2 causes the cache to overflow, evicting the prefetch
  38 |     // for the Page 0 link.
> 39 |     await act(
     |           ^
  40 |       async () => {
  41 |         await switchToTab2.click()
  42 |       },

  at Object.act (e2e/app-dir/segment-cache/memory-pressure/segment-cache-memory-pressure.test.ts:39:11)

● segment cache memory pressure › does not leak memory when repeatedly triggering prefetches

thrown: "Exceeded timeout of 120000 ms for a test.
Add a timeout value to this test to increase the timeout, if this is a long-running test. See https://jestjs.io/docs/api#testname-fn-timeout."

  546 |           gatedBodies.has(callback)
  547 |         ) {
> 548 |           return Reflect.apply(target, thisArg, args)
      |                          ^
  549 |         }
  550 |
  551 |         const applicable = [...describeGateStack]

  at Object.apply (lib/gate/runtime.ts:548:26)
  at Object.apply (lib/e2e-utils/index.ts:65:30)
  at it (e2e/app-dir/segment-cache/memory-pressure/segment-cache-memory-pressure.test.ts:67:3)
  at Object.describe (e2e/app-dir/segment-cache/memory-pressure/segment-cache-memory-pressure.test.ts:5:1)

pnpm test-start test/e2e/app-dir/segment-cache/prefetch-scheduling/prefetch-scheduling.test.ts (job)

segment cache prefetch scheduling > increases the priority of a viewport-initiated prefetch on hover (DD)
segment cache prefetch scheduling > reserve special bandwidth for the most recently hovered link (DD)
segment cache prefetch scheduling > reschedules a link's prefetch when it re-enters the viewport (DD)

Expand output

● segment cache prefetch scheduling › increases the priority of a viewport-initiated prefetch on hover

Expected sequence of responses does not match:

- Expected
+ Received

  Array [
    "Content of page 2",
    "Content of page 6",
-   "Content of page 4",
  ]

NOTE: Assertions are checked in order, so if an expectation is missing, it may have actually appeared earlier in the sequence than expected. Make sure the order is correct.

  21 |
  22 |     const checkbox = await browser.elementByCss('input[type="checkbox"]')
> 23 |     await act(
     |           ^
  24 |       async () => {
  25 |         // Reveal the links to start prefetching, but block the responses from
  26 |         // reaching the client. This will initiate prefetches for the route

  at Object.act (e2e/app-dir/segment-cache/prefetch-scheduling/prefetch-scheduling.test.ts:23:11)

● segment cache prefetch scheduling › reserve special bandwidth for the most recently hovered link

Expected sequence of responses does not match:

- Expected
+ Received

- Array [
-   "Content of page 6",
-   "Content of page 8",
-   "Content of page 5",
- ]
+ Array []

NOTE: Assertions are checked in order, so if an expectation is missing, it may have actually appeared earlier in the sequence than expected. Make sure the order is correct.

  142 |
  143 |     const checkbox = await browser.elementByCss('input[type="checkbox"]')
> 144 |     await act(async () => {
      |           ^
  145 |       // Reveal the links to start prefetching, but block the responses from
  146 |       // reaching the client. This will initiate prefetches for the route
  147 |       // trees, but it won't start prefetching any segment data yet until the

  at Object.act (e2e/app-dir/segment-cache/prefetch-scheduling/prefetch-scheduling.test.ts:144:11)

● segment cache prefetch scheduling › reschedules a link's prefetch when it re-enters the viewport

Expected a response containing the given string:

Content of page 5

  282 |     // Now we'll reveal the links again to verify that the prefetch tasks are
  283 |     // rescheduled, after having been canceled.
> 284 |     await act(
      |           ^
  285 |       async () => {
  286 |         await checkbox.click()
  287 |       },

  at Object.act (e2e/app-dir/segment-cache/prefetch-scheduling/prefetch-scheduling.test.ts:284:11)

pnpm test-start test/e2e/app-dir/segment-cache/search-params/segment-cache-search-params.test.ts (job)

segment cache (search params) > when fetching without PPR (e.g. prefetch="unstable_forceStale"), includes the search params in the cache key (DD)

Expand output

● segment cache (search params) › when fetching without PPR (e.g. prefetch="unstable_forceStale"), includes the search params in the cache key

Expected a response containing the given string:

target-page-with-search-param

   98 |       'input[data-link-accordion="/search-params/target-page?searchParam=a_PPR"]'
   99 |     )
> 100 |     await act(
      |           ^
  101 |       async () => {
  102 |         await revealA.click()
  103 |       },

  at Object.act (e2e/app-dir/segment-cache/search-params/segment-cache-search-params.test.ts:100:11)

pnpm test-start test/e2e/app-dir/segment-cache/vary-params/vary-params.test.ts (job)

segment cache - vary params > tracks param access in generateMetadata (DD)
segment cache - vary params > reuses page segment when layout varies but page does not (DD)

Expand output

● segment cache - vary params › tracks param access in generateMetadata

Timed out waiting for a request to be initiated.

  358 |     // Second prefetch: head re-fetched (metadata varies on slug),
  359 |     // but body is cached (body doesn't access slug)
> 360 |     await act(async () => {
      |           ^
  361 |       const toggle = await browser.elementByCss(
  362 |         'input[data-link-accordion="/metadata/bbb"]'
  363 |       )

  at Object.act (e2e/app-dir/segment-cache/vary-params/vary-params.test.ts:360:11)

● segment cache - vary params › reuses page segment when layout varies but page does not

Timed out waiting for a request to be initiated.

  423 |     // Second prefetch: layout re-fetched (varies on item),
  424 |     // page is cached (only varies on category)
> 425 |     await act(async () => {
      |           ^
  426 |       const toggle = await browser.elementByCss(
  427 |         'input[data-link-accordion="/page-reuse/electronics/tablet"]'
  428 |       )

  at Object.act (e2e/app-dir/segment-cache/vary-params/vary-params.test.ts:425:11)

pnpm test-start-turbo test/e2e/app-dir/segment-cache/vary-params/vary-params.test.ts (turbopack) (job)

segment cache - vary params > tracks param access in generateMetadata (DD)
segment cache - vary params > reuses page segment when layout varies but page does not (DD)

Expand output

● segment cache - vary params › tracks param access in generateMetadata

Timed out waiting for a request to be initiated.

  358 |     // Second prefetch: head re-fetched (metadata varies on slug),
  359 |     // but body is cached (body doesn't access slug)
> 360 |     await act(async () => {
      |           ^
  361 |       const toggle = await browser.elementByCss(
  362 |         'input[data-link-accordion="/metadata/bbb"]'
  363 |       )

  at Object.act (e2e/app-dir/segment-cache/vary-params/vary-params.test.ts:360:11)

● segment cache - vary params › reuses page segment when layout varies but page does not

Timed out waiting for a request to be initiated.

  423 |     // Second prefetch: layout re-fetched (varies on item),
  424 |     // page is cached (only varies on category)
> 425 |     await act(async () => {
      |           ^
  426 |       const toggle = await browser.elementByCss(
  427 |         'input[data-link-accordion="/page-reuse/electronics/tablet"]'
  428 |       )

  at Object.act (e2e/app-dir/segment-cache/vary-params/vary-params.test.ts:425:11)

pnpm test-start-turbo test/production/app-dir/app-fetch-build-cache/app-fetch-build-cache.test.ts (turbopack) (job)

app fetch build cache > should not use stale data if present (DD)

Expand output

● app fetch build cache › should not use stale data if present

thrown: "Exceeded timeout of 60000 ms for a test.
Add a timeout value to this test to increase the timeout, if this is a long-running test. See https://jestjs.io/docs/api#testname-fn-timeout."

  546 |           gatedBodies.has(callback)
  547 |         ) {
> 548 |           return Reflect.apply(target, thisArg, args)
      |                          ^
  549 |         }
  550 |
  551 |         const applicable = [...describeGateStack]

  at Object.apply (lib/gate/runtime.ts:548:26)
  at Object.apply (lib/e2e-utils/index.ts:65:30)
  at it (production/app-dir/app-fetch-build-cache/app-fetch-build-cache.test.ts:18:3)
  at Object.describe (production/app-dir/app-fetch-build-cache/app-fetch-build-cache.test.ts:3:1)

pnpm test-start-turbo test/e2e/app-dir/segment-cache/prefetch-scheduling/prefetch-scheduling.test.ts (turbopack) (job)

segment cache prefetch scheduling > increases the priority of a viewport-initiated prefetch on hover (DD)
segment cache prefetch scheduling > reserve special bandwidth for the most recently hovered link (DD)
segment cache prefetch scheduling > reschedules a link's prefetch when it re-enters the viewport (DD)

Expand output

● segment cache prefetch scheduling › increases the priority of a viewport-initiated prefetch on hover

Expected sequence of responses does not match:

- Expected
+ Received

  Array [
    "Content of page 2",
    "Content of page 6",
-   "Content of page 4",
  ]

NOTE: Assertions are checked in order, so if an expectation is missing, it may have actually appeared earlier in the sequence than expected. Make sure the order is correct.

  21 |
  22 |     const checkbox = await browser.elementByCss('input[type="checkbox"]')
> 23 |     await act(
     |           ^
  24 |       async () => {
  25 |         // Reveal the links to start prefetching, but block the responses from
  26 |         // reaching the client. This will initiate prefetches for the route

  at Object.act (e2e/app-dir/segment-cache/prefetch-scheduling/prefetch-scheduling.test.ts:23:11)

● segment cache prefetch scheduling › reserve special bandwidth for the most recently hovered link

Expected sequence of responses does not match:

- Expected
+ Received

- Array [
-   "Content of page 6",
-   "Content of page 8",
-   "Content of page 5",
- ]
+ Array []

NOTE: Assertions are checked in order, so if an expectation is missing, it may have actually appeared earlier in the sequence than expected. Make sure the order is correct.

  142 |
  143 |     const checkbox = await browser.elementByCss('input[type="checkbox"]')
> 144 |     await act(async () => {
      |           ^
  145 |       // Reveal the links to start prefetching, but block the responses from
  146 |       // reaching the client. This will initiate prefetches for the route
  147 |       // trees, but it won't start prefetching any segment data yet until the

  at Object.act (e2e/app-dir/segment-cache/prefetch-scheduling/prefetch-scheduling.test.ts:144:11)

● segment cache prefetch scheduling › reschedules a link's prefetch when it re-enters the viewport

Expected a response containing the given string:

Content of page 5

  282 |     // Now we'll reveal the links again to verify that the prefetch tasks are
  283 |     // rescheduled, after having been canceled.
> 284 |     await act(
      |           ^
  285 |       async () => {
  286 |         await checkbox.click()
  287 |       },

  at Object.act (e2e/app-dir/segment-cache/prefetch-scheduling/prefetch-scheduling.test.ts:284:11)

pnpm test-start-turbo test/e2e/app-dir/segment-cache/memory-pressure/segment-cache-memory-pressure.test.ts (turbopack) (job)

segment cache memory pressure > evicts least recently used prefetch data once cache size exceeds limit (DD)
segment cache memory pressure > does not leak memory when repeatedly triggering prefetches (DD)

Expand output

● segment cache memory pressure › evicts least recently used prefetch data once cache size exceeds limit

Timed out waiting for a request to be initiated.

  37 |     // Switching to tab 2 causes the cache to overflow, evicting the prefetch
  38 |     // for the Page 0 link.
> 39 |     await act(
     |           ^
  40 |       async () => {
  41 |         await switchToTab2.click()
  42 |       },

  at Object.act (e2e/app-dir/segment-cache/memory-pressure/segment-cache-memory-pressure.test.ts:39:11)

● segment cache memory pressure › does not leak memory when repeatedly triggering prefetches

thrown: "Exceeded timeout of 120000 ms for a test.
Add a timeout value to this test to increase the timeout, if this is a long-running test. See https://jestjs.io/docs/api#testname-fn-timeout."

  546 |           gatedBodies.has(callback)
  547 |         ) {
> 548 |           return Reflect.apply(target, thisArg, args)
      |                          ^
  549 |         }
  550 |
  551 |         const applicable = [...describeGateStack]

  at Object.apply (lib/gate/runtime.ts:548:26)
  at Object.apply (lib/e2e-utils/index.ts:65:30)
  at it (e2e/app-dir/segment-cache/memory-pressure/segment-cache-memory-pressure.test.ts:67:3)
  at Object.describe (e2e/app-dir/segment-cache/memory-pressure/segment-cache-memory-pressure.test.ts:5:1)

pnpm test-start-turbo test/e2e/app-dir/segment-cache/search-params/segment-cache-search-params.test.ts (turbopack) (job)

segment cache (search params) > when fetching without PPR (e.g. prefetch="unstable_forceStale"), includes the search params in the cache key (DD)

Expand output

● segment cache (search params) › when fetching without PPR (e.g. prefetch="unstable_forceStale"), includes the search params in the cache key

Expected a response containing the given string:

target-page-with-search-param

   98 |       'input[data-link-accordion="/search-params/target-page?searchParam=a_PPR"]'
   99 |     )
> 100 |     await act(
      |           ^
  101 |       async () => {
  102 |         await revealA.click()
  103 |       },

  at Object.act (e2e/app-dir/segment-cache/search-params/segment-cache-search-params.test.ts:100:11)

[PPF] Fix missing runtime-follow up if hints are stale

f31bfbe

lubieowoce force-pushed the lubieowoce/fix-runtime-followup branch from 6779b37 to f31bfbe Compare September 4, 2026 22:03

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[PPF] Fix missing runtime-follow up if hints are stale - #98278

[PPF] Fix missing runtime-follow up if hints are stale#98278
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lubieowoce commented Sep 4, 2026

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lubieowoce commented Sep 4, 2026

Edge cases

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github-actions Bot commented Sep 4, 2026 •

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