next.js

610bc9e4 - Refactor: Decouple request store creation from `req` / `res` (#93499)

Refactor: Decouple request store creation from `req` / `res` (#93499) This PR refactors `createRequestStoreImpl` into a new exported `createRequestStore` function that takes a serializable `RequestStoreInputs` shape (`headers`, optional `onUpdateCookies`, `url`, etc.) instead of a concrete `req` / `res` pair. The existing `createRequestStoreForRender` and `createRequestStoreForAPI` wrappers continue to take `(req, res, ...)` and translate to the new shape internally — there is no behavioral change for any existing code path. Two transitive refactors are included in this change, motivated by the same goal of removing the dependency on `IncomingMessage` / `BaseNextRequest` / `NextRequest` from the inner construction: - `checkIsOnDemandRevalidate(req, previewProps)` becomes `checkIsOnDemandRevalidate(rawHeaders, previewProps)`. Every call site now passes `req.headers` (or equivalent) rather than the whole request. The function only ever read `req.headers`, so this is purely a signature cleanup. - `DraftModeProvider`'s constructor takes `headers` instead of `req`. Its draft-mode lookup also only needed the headers to call `checkIsOnDemandRevalidate`, so the dependency on the request types is no longer load-bearing. `mergeMiddlewareCookies` similarly takes `headers` instead of `req`, but keeps its original `'x-middleware-set-cookie' in headers` + bracket-access pattern — preserving the pre-refactor behavior exactly (silent no-op for Web `Headers`, full merge for Node `IncomingHttpHeaders`). A `TODO` comment flags the open question of whether `Headers` callers need this merge or already handle it elsewhere. That's an investigation for a separate change. This change is groundwork for an upcoming `'use cache'` deadlock-detection probe (see the `RequestStoreInputs` doc comment). The probe runs the same cache fill in an isolated worker process when the main fill stalls, and needs to construct a real `RequestStore` from a serialized snapshot of the outer request's headers / cookies / etc. — without access to the original `req` / `res` objects, which can't cross the worker boundary. With this refactor, the probe worker can call `createRequestStore` directly with the forwarded inputs and get a fully-functional store (real `headers`, `cookies`, `draftMode`, `mutableCookies`, `userspaceMutableCookies`), rather than building a stub that throws on access.