add failing test for unresolved prefetch promises by ztanner · Pull Request #89339 · vercel/next.js

ztanner · 2026-01-31T15:27:39Z

Adds a failing test proving that if the RSC response from a prefetch contains an unresolved promise, navigating to the page will cause the Suspense boundary wrapping the use of that promise to remain in fallback state indefinitely.

This appears to have regressed in e9a03ac

x-ref: #89170

ztanner · 2026-01-31T15:27:59Z

add handling to skip prefetch payloads if partial #89340
add failing test for unresolved prefetch promises #89339 👈 (View in Graphite)
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nextjs-bot · 2026-01-31T15:30:58Z

Failing test suites

Commit: bc1adb2 | About building and testing Next.js

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

prefetch-partial-rsc > resolves after a client-side navigation (DD)

Expand output

● prefetch-partial-rsc › resolves after a client-side navigation

page.waitForSelector: Timeout 5000ms exceeded.
Call log:
  - waiting for locator('#user') to be visible

  519 |
  520 |     return this.startChain(async () => {
> 521 |       const el = await page.waitForSelector(selector, {
      |                             ^
  522 |         timeout,
  523 |         state,
  524 |       })

  at waitForSelector (lib/browsers/playwright.ts:521:29)
  at Playwright._chain (lib/browsers/playwright.ts:651:23)
  at Playwright._chain [as startChain] (lib/browsers/playwright.ts:632:17)
  at Playwright.startChain [as waitForElementByCss] (lib/browsers/playwright.ts:520:17)
  at Playwright.waitForElementByCss [as elementByCss] (lib/browsers/playwright.ts:405:17)
  at elementByCss (e2e/app-dir/segment-cache/prefetch-partial-rsc/prefetch-partial-rsc.test.ts:13:34)
  at fn (lib/next-test-utils.ts:831:20)
  at Object.<anonymous> (e2e/app-dir/segment-cache/prefetch-partial-rsc/prefetch-partial-rsc.test.ts:12:5)
  at Proxy._chain (lib/browsers/playwright.ts:651:23)
  at Proxy._chain (lib/browsers/playwright.ts:627:17)
  at Proxy.continueChain (lib/browsers/playwright.ts:433:17)
  at text (e2e/app-dir/segment-cache/prefetch-partial-rsc/prefetch-partial-rsc.test.ts:13:56)
  at fn (lib/next-test-utils.ts:831:20)
  at Object.<anonymous> (e2e/app-dir/segment-cache/prefetch-partial-rsc/prefetch-partial-rsc.test.ts:12:5)

nextjs-bot · 2026-01-31T15:45:39Z

Stats from current PR

✅ No significant changes detected

📊 All Metrics

📖 Metrics Glossary

Dev Server Metrics:

Listen = TCP port starts accepting connections
First Request = HTTP server returns successful response
Cold = Fresh build (no cache)
Warm = With cached build artifacts

Build Metrics:

Fresh = Clean build (no .next directory)
Cached = With existing .next directory

Change Thresholds:

Time: Changes < 50ms AND < 10%, OR < 2% are insignificant
Size: Changes < 1KB AND < 1% are insignificant
All other changes are flagged to catch regressions

⚡ Dev Server

Metric	Canary	PR	Change	Trend
Cold (Listen)	456ms	455ms	✓	▁█▁▁▁
Cold (Ready in log)	438ms	437ms	✓	▂█▁▂▂
Cold (First Request)	1.180s	1.160s	✓	▂█▁▅▄
Warm (Listen)	457ms	456ms	✓	▁█▁▁▁
Warm (Ready in log)	441ms	445ms	✓	▁█▁▁▁
Warm (First Request)	340ms	340ms	✓	▂█▁▂▁

📦 Dev Server (Webpack) (Legacy)

📦 Dev Server (Webpack)

Metric	Canary	PR	Change	Trend
Cold (Listen)	456ms	455ms	✓	█▁█▁█
Cold (Ready in log)	437ms	439ms	✓	▆▆▇▅▆
Cold (First Request)	1.850s	1.867s	✓	▄▃▅▃▃
Warm (Listen)	456ms	455ms	✓	▁▅▅█▅
Warm (Ready in log)	438ms	438ms	✓	▅▄▅▄▄
Warm (First Request)	1.878s	1.864s	✓	▄▃▅▃▃

⚡ Production Builds

Metric	Canary	PR	Change	Trend
Fresh Build	3.905s	3.950s	✓	▃█▂▁▁
Cached Build	3.866s	3.832s	✓	▃█▂▁▁

📦 Production Builds (Webpack) (Legacy)

📦 Production Builds (Webpack)

Metric	Canary	PR	Change	Trend
Fresh Build	13.759s	13.768s	✓	▂▁▄▁▁
Cached Build	13.865s	13.881s	✓	▂▁▄▁▁
node_modules Size	464 MB	464 MB	✓	▁▁▁▁▁

📦 Bundle Sizes

Bundle Sizes

⚡ Turbopack

Client

Main Bundles: **434 kB** → **434 kB** ✅ -11 B

81 files with content-based hashes (individual files not comparable between builds)

Server

Middleware

	Canary	PR	Change
middleware-b..fest.js gzip	763 B	770 B	✓
Total	763 B	770 B	⚠️ +7 B

Build Details

Build Manifests

	Canary	PR	Change
_buildManifest.js gzip	451 B	450 B	✓
Total	451 B	450 B	✅ -1 B

📦 Webpack

Client

Main Bundles

	Canary	PR	Change
5528-HASH.js gzip	5.47 kB	N/A	-
6280-HASH.js gzip	54.5 kB	N/A	-
6335.HASH.js gzip	169 B	N/A	-
912-HASH.js gzip	4.53 kB	N/A	-
e8aec2e4-HASH.js gzip	62.5 kB	N/A	-
framework-HASH.js gzip	59.7 kB	59.7 kB	✓
main-app-HASH.js gzip	256 B	255 B	✓
main-HASH.js gzip	39 kB	39 kB	✓
webpack-HASH.js gzip	1.68 kB	1.68 kB	✓
262-HASH.js gzip	N/A	4.52 kB	-
2889.HASH.js gzip	N/A	169 B	-
5602-HASH.js gzip	N/A	5.48 kB	-
6948ada0-HASH.js gzip	N/A	62.5 kB	-
9544-HASH.js gzip	N/A	55.2 kB	-
Total	228 kB	228 kB	⚠️ +672 B

Polyfills

	Canary	PR	Change
polyfills-HASH.js gzip	39.4 kB	39.4 kB	✓
Total	39.4 kB	39.4 kB	✓

Pages

	Canary	PR	Change
_app-HASH.js gzip	194 B	194 B	✓
_error-HASH.js gzip	183 B	180 B	🟢 3 B (-2%)
css-HASH.js gzip	331 B	330 B	✓
dynamic-HASH.js gzip	1.81 kB	1.81 kB	✓
edge-ssr-HASH.js gzip	256 B	256 B	✓
head-HASH.js gzip	351 B	352 B	✓
hooks-HASH.js gzip	384 B	383 B	✓
image-HASH.js gzip	580 B	581 B	✓
index-HASH.js gzip	260 B	260 B	✓
link-HASH.js gzip	2.49 kB	2.49 kB	✓
routerDirect..HASH.js gzip	320 B	319 B	✓
script-HASH.js gzip	386 B	386 B	✓
withRouter-HASH.js gzip	315 B	315 B	✓
1afbb74e6ecf..834.css gzip	106 B	106 B	✓
Total	7.97 kB	7.97 kB	✅ -1 B

Server

Edge SSR

	Canary	PR	Change
edge-ssr.js gzip	126 kB	126 kB	✓
page.js gzip	248 kB	249 kB	✓
Total	375 kB	375 kB	⚠️ +132 B

Middleware

	Canary	PR	Change
middleware-b..fest.js gzip	617 B	614 B	✓
middleware-r..fest.js gzip	156 B	155 B	✓
middleware.js gzip	33.3 kB	33.2 kB	✓
edge-runtime..pack.js gzip	842 B	842 B	✓
Total	34.9 kB	34.8 kB	✅ -120 B

Build Details

Build Manifests

	Canary	PR	Change
_buildManifest.js gzip	732 B	736 B	✓
Total	732 B	736 B	⚠️ +4 B

Build Cache

	Canary	PR	Change
0.pack gzip	3.8 MB	3.8 MB	🔴 +5.92 kB (+0%)
index.pack gzip	102 kB	102 kB	✓
index.pack.old gzip	103 kB	101 kB	🟢 2.28 kB (-2%)
Total	4 MB	4.01 MB	⚠️ +3.44 kB

🔄 Shared (bundler-independent)

Runtimes

	Canary	PR	Change
app-page-exp...dev.js gzip	311 kB	311 kB	✓
app-page-exp..prod.js gzip	166 kB	166 kB	✓
app-page-tur...dev.js gzip	311 kB	311 kB	✓
app-page-tur..prod.js gzip	166 kB	166 kB	✓
app-page-tur...dev.js gzip	308 kB	308 kB	✓
app-page-tur..prod.js gzip	164 kB	164 kB	✓
app-page.run...dev.js gzip	308 kB	308 kB	✓
app-page.run..prod.js gzip	164 kB	164 kB	✓
app-route-ex...dev.js gzip	70.4 kB	70.4 kB	✓
app-route-ex..prod.js gzip	48.9 kB	48.9 kB	✓
app-route-tu...dev.js gzip	70.4 kB	70.4 kB	✓
app-route-tu..prod.js gzip	49 kB	49 kB	✓
app-route-tu...dev.js gzip	70 kB	70 kB	✓
app-route-tu..prod.js gzip	48.7 kB	48.7 kB	✓
app-route.ru...dev.js gzip	70 kB	70 kB	✓
app-route.ru..prod.js gzip	48.7 kB	48.7 kB	✓
dist_client_...dev.js gzip	324 B	324 B	✓
dist_client_...dev.js gzip	326 B	326 B	✓
dist_client_...dev.js gzip	318 B	318 B	✓
dist_client_...dev.js gzip	317 B	317 B	✓
pages-api-tu...dev.js gzip	43.1 kB	43.1 kB	✓
pages-api-tu..prod.js gzip	32.9 kB	32.9 kB	✓
pages-api.ru...dev.js gzip	43.1 kB	43.1 kB	✓
pages-api.ru..prod.js gzip	32.8 kB	32.8 kB	✓
pages-turbo....dev.js gzip	52.4 kB	52.4 kB	✓
pages-turbo...prod.js gzip	39.4 kB	39.4 kB	✓
pages.runtim...dev.js gzip	52.4 kB	52.4 kB	✓
pages.runtim..prod.js gzip	39.3 kB	39.3 kB	✓
server.runti..prod.js gzip	62.5 kB	62.5 kB	✓
Total	2.77 MB	2.77 MB	✅ -3 B

add failing test for unresolved prefetch promises

bc1adb2

nextjs-bot added created-by: Next.js team PRs by the Next.js team. tests labels Jan 31, 2026

ztanner mentioned this pull request Jan 31, 2026

add handling to skip prefetch payloads if partial #89340

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add failing test for unresolved prefetch promises#89339

add failing test for unresolved prefetch promises#89339
ztanner wants to merge 1 commit intocanaryfrom
01-31-add_failing_test_for_unresolved_prefetch_promises

ztanner commented Jan 31, 2026 •

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nextjs-bot commented Jan 31, 2026

Failing test suites

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nextjs-bot commented Jan 31, 2026

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ztanner commented Jan 31, 2026 •

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