Emit the static paths HMR update after updating the cache#96019
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In dev, the server sends a `SERVER_COMPONENT_CHANGES` HMR update when `generateStaticParams` produces a different set of static paths, so the render picks up the new `fallbackParams` (added in #85741). It was emitting that update before writing the new result to `staticPathsCache`, so the refresh it triggered could read the previous, stale result and keep rendering with the old `fallbackParams` (there are `await`s for the prerender manifest between the two points, which widens the window). This moves the emit to after `staticPathsCache.set`, so the triggered refresh always observes the updated result. This also adds the end-to-end regression test that was missing for this behavior. Reusing the existing `use-cache-params/[slug]` fixture, it asserts the blocking-route redbox shown when a route reads a fallback (unknown) param outside a Suspense boundary, then adds a `generateStaticParams` covering the requested slug and asserts the redbox clears. Editing the page produces two refreshes: the one the edit itself triggers, which still renders with the stale `fallbackParams`, and the follow-up update this code emits once the new result is cached, which renders with the fresh ones. To ensure the test only passes because of the latter, `generateStaticParams` is given a deliberate delay so its recompute finishes only after the edit's own refresh has already re-rendered with the stale params. closes NAR-496
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View diffspages-api.ru..time.prod.jsDiff too large to display pages.runtime.prod.jsDiff too large to display 📎 Tarball URLCommit: 7ea9270 |
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Tests PassedCommit: 7ea9270 |
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marked this pull request as ready for review
July 21, 2026 22:10
devjiwonchoi
approved these changes
Jul 22, 2026
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In dev, the server sends a
SERVER_COMPONENT_CHANGESHMR update whengenerateStaticParamsproduces a different set of static paths, so the render picks up the newfallbackParams(added in #85741). It was emitting that update before writing the new result tostaticPathsCache, so the refresh it triggered could read the previous, stale result and keep rendering with the oldfallbackParams(there areawaits for the prerender manifest between the two points, which widens the window). This moves the emit to afterstaticPathsCache.set, so the triggered refresh always observes the updated result.This also adds the end-to-end regression test that was missing for this behavior. Reusing the existing
use-cache-params/[slug]fixture, it asserts the blocking-route redbox shown when a route reads a fallback (unknown) param outside a Suspense boundary, then adds agenerateStaticParamscovering the requested slug and asserts the redbox clears. Editing the page produces two refreshes: the one the edit itself triggers, which still renders with the stalefallbackParams, and the follow-up update this code emits once the new result is cached, which renders with the fresh ones. To ensure the test only passes because of the latter,generateStaticParamsis given a deliberate delay so its recompute finishes only after the edit's own refresh has already re-rendered with the stale params.closes NAR-496
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