fix async action queue behavior

[ztanner]

What?

When the router action queue receives a bunch of async actions in quick succession, some of those requests are dropped, and as a result, anything observing pending transitions will be stuck in a pending state.

Why?

When adding items to the action queue, the intended behavior is for new actions to be added to the end of the action queue, to be picked up by runRemainingActions once the in-flight action is processed. However, new actions are erroneously overwriting pending actions in the queue rather than appending them, as actionQueue.last might have a pending action attached to it.

How?

This moves the assignment of actionQueue.last to always be in dispatchAction, rather than the function that processes the action, so that we always have a single spot where last is assigned and to prevent it from erroneously omitted/overwritten.

Fixes #59011

[ztanner]

Current dependencies on/for this PR:

• canary
  • PR fix async action queue behavior #59038 👈

This stack of pull requests is managed by Graphite.

[ijjk]

Stats from current PR

Default Build

General Overall increase ⚠️

	vercel/next.js canary	vercel/next.js 11-28-fix_async_action_queue_behavior	Change
buildDuration	10.3s	10.5s	⚠️ +178ms
buildDurationCached	5.9s	6.1s	⚠️ +254ms
nodeModulesSize	199 MB	199 MB	⚠️ +840 B
nextStartRea..uration (ms)	421ms	421ms	✓

Client Bundles (main, webpack)

	vercel/next.js canary	vercel/next.js 11-28-fix_async_action_queue_behavior	Change
199-HASH.js gzip	28.7 kB	28.7 kB	N/A
3f784ff6-HASH.js gzip	53.3 kB	53.3 kB	✓
494.HASH.js gzip	180 B	181 B	N/A
framework-HASH.js gzip	45.2 kB	45.2 kB	✓
main-app-HASH.js gzip	241 B	238 B	N/A
main-HASH.js gzip	31.7 kB	31.7 kB	N/A
webpack-HASH.js gzip	1.7 kB	1.7 kB	✓
Overall change	100 kB	100 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	vercel/next.js 11-28-fix_async_action_queue_behavior	Change
polyfills-HASH.js gzip	31 kB	31 kB	✓
Overall change	31 kB	31 kB	✓

Client Pages

	vercel/next.js canary	vercel/next.js 11-28-fix_async_action_queue_behavior	Change
_app-HASH.js gzip	194 B	195 B	N/A
_error-HASH.js gzip	182 B	181 B	N/A
amp-HASH.js gzip	501 B	503 B	N/A
css-HASH.js gzip	322 B	323 B	N/A
dynamic-HASH.js gzip	2.5 kB	2.5 kB	✓
edge-ssr-HASH.js gzip	253 B	255 B	N/A
head-HASH.js gzip	348 B	347 B	N/A
hooks-HASH.js gzip	369 B	368 B	N/A
image-HASH.js gzip	4.27 kB	4.27 kB	N/A
index-HASH.js gzip	256 B	256 B	✓
link-HASH.js gzip	2.61 kB	2.6 kB	N/A
routerDirect..HASH.js gzip	311 B	311 B	✓
script-HASH.js gzip	384 B	383 B	N/A
withRouter-HASH.js gzip	307 B	308 B	N/A
1afbb74e6ecf..834.css gzip	106 B	106 B	✓
Overall change	3.17 kB	3.17 kB	✓

Client Build Manifests

	vercel/next.js canary	vercel/next.js 11-28-fix_async_action_queue_behavior	Change
_buildManifest.js gzip	484 B	483 B	N/A
Overall change	0 B	0 B	✓

Rendered Page Sizes

	vercel/next.js canary	vercel/next.js 11-28-fix_async_action_queue_behavior	Change
index.html gzip	528 B	527 B	N/A
link.html gzip	538 B	541 B	N/A
withRouter.html gzip	524 B	522 B	N/A
Overall change	0 B	0 B	✓

Edge SSR bundle Size

	vercel/next.js canary	vercel/next.js 11-28-fix_async_action_queue_behavior	Change
edge-ssr.js gzip	92.5 kB	92.5 kB	N/A
page.js gzip	145 kB	145 kB	N/A
Overall change	0 B	0 B	✓

Middleware size

	vercel/next.js canary	vercel/next.js 11-28-fix_async_action_queue_behavior	Change
middleware-b..fest.js gzip	625 B	625 B	✓
middleware-r..fest.js gzip	150 B	151 B	N/A
middleware.js gzip	35.6 kB	35.6 kB	N/A
edge-runtime..pack.js gzip	1.92 kB	1.92 kB	✓
Overall change	2.55 kB	2.55 kB	✓

Next Runtimes

	vercel/next.js canary	vercel/next.js 11-28-fix_async_action_queue_behavior	Change
app-page-exp...dev.js gzip	167 kB	167 kB	✓
app-page-exp..prod.js gzip	93.5 kB	93.5 kB	✓
app-page-tur..prod.js gzip	94.3 kB	94.3 kB	✓
app-page-tur..prod.js gzip	88.8 kB	88.8 kB	✓
app-page.run...dev.js gzip	137 kB	137 kB	✓
app-page.run..prod.js gzip	88.2 kB	88.2 kB	✓
app-route-ex...dev.js gzip	23.8 kB	23.8 kB	✓
app-route-ex..prod.js gzip	16.5 kB	16.5 kB	✓
app-route-tu..prod.js gzip	16.5 kB	16.5 kB	✓
app-route-tu..prod.js gzip	16 kB	16 kB	✓
app-route.ru...dev.js gzip	23.2 kB	23.2 kB	✓
app-route.ru..prod.js gzip	16 kB	16 kB	✓
pages-api-tu..prod.js gzip	9.37 kB	9.37 kB	✓
pages-api.ru...dev.js gzip	9.64 kB	9.64 kB	✓
pages-api.ru..prod.js gzip	9.37 kB	9.37 kB	✓
pages-turbo...prod.js gzip	21.9 kB	21.9 kB	✓
pages.runtim...dev.js gzip	22.5 kB	22.5 kB	✓
pages.runtim..prod.js gzip	21.9 kB	21.9 kB	✓
server.runti..prod.js gzip	49.2 kB	49.2 kB	✓
Overall change	925 kB	925 kB	✓

Diff details

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Diff for 199-HASH.js

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Commit: 98d5298

[ijjk]

Tests Passed