move segment cache entries to top level segment-cache dir

packages/next/src/client/app-dir/form.tsx

@@ -19,7 +19,7 @@ import {
   mountFormInstance,
   unmountPrefetchableInstance,
 } from '../components/links'
-import { FetchStrategy } from '../components/segment-cache'
+import { FetchStrategy } from '../components/segment-cache/types'
 
 export type { FormProps }
 

packages/next/src/client/app-dir/link.tsx

@@ -21,7 +21,7 @@ import { isLocalURL } from '../../shared/lib/router/utils/is-local-url'
 import {
   FetchStrategy,
   type PrefetchTaskFetchStrategy,
-} from '../components/segment-cache'
+} from '../components/segment-cache/types'
 import { errorOnce } from '../../shared/lib/utils/error-once'
 
 type Url = string | UrlObject

packages/next/src/client/components/app-router-instance.ts

@@ -16,9 +16,9 @@ import { startTransition } from 'react'
 import { isThenable } from '../../shared/lib/is-thenable'
 import {
   FetchStrategy,
-  prefetch as prefetchWithSegmentCache,
   type PrefetchTaskFetchStrategy,
-} from './segment-cache'
+} from './segment-cache/types'
+import { prefetch as prefetchWithSegmentCache } from './segment-cache/prefetch'
 import { dispatchAppRouterAction } from './use-action-queue'
 import { addBasePath } from '../add-base-path'
 import { isExternalURL } from './app-router-utils'

packages/next/src/client/components/links.ts

@@ -2,17 +2,17 @@ import type { FlightRouterState } from '../../shared/lib/app-router-types'
 import type { AppRouterInstance } from '../../shared/lib/app-router-context.shared-runtime'
 import {
   FetchStrategy,
-  isPrefetchTaskDirty,
   type PrefetchTaskFetchStrategy,
-} from './segment-cache'
-import { createCacheKey } from './segment-cache'
+  PrefetchPriority,
+} from './segment-cache/types'
+import { createCacheKey } from './segment-cache/cache-key'
 import {
   type PrefetchTask,
-  PrefetchPriority,
   schedulePrefetchTask as scheduleSegmentPrefetchTask,
   cancelPrefetchTask,
   reschedulePrefetchTask,
-} from './segment-cache'
+  isPrefetchTaskDirty,
+} from './segment-cache/scheduler'
 import { startTransition } from 'react'
 
 type LinkElement = HTMLAnchorElement | SVGAElement

packages/next/src/client/components/router-reducer/fetch-server-response.ts

@@ -40,7 +40,7 @@ import {
   getRenderedSearch,
   urlToUrlWithoutFlightMarker,
 } from '../../route-params'
-import type { NormalizedSearch } from '../segment-cache'
+import type { NormalizedSearch } from '../segment-cache/cache-key'
 
 const createFromReadableStream =
   createFromReadableStreamBrowser as (typeof import('react-server-dom-webpack/client.browser'))['createFromReadableStream']

packages/next/src/client/components/router-reducer/reducers/navigate-reducer.ts

@@ -13,10 +13,10 @@ import { handleMutable } from '../handle-mutable'
 
 import {
   navigate as navigateUsingSegmentCache,
-  NavigationResultTag,
   type NavigationResult,
-  getStaleTimeMs,
-} from '../../segment-cache'
+} from '../../segment-cache/navigation'
+import { NavigationResultTag } from '../../segment-cache/types'
+import { getStaleTimeMs } from '../../segment-cache/cache'
 
 // These values are set by `define-env-plugin` (based on `nextConfig.experimental.staleTimes`)
 // and default to 5 minutes (static) / 0 seconds (dynamic)

packages/next/src/client/components/router-reducer/reducers/refresh-reducer.ts

@@ -19,7 +19,7 @@ import { createEmptyCacheNode } from '../../app-router'
 import { handleSegmentMismatch } from '../handle-segment-mismatch'
 import { hasInterceptionRouteInCurrentTree } from './has-interception-route-in-current-tree'
 import { refreshInactiveParallelSegments } from '../refetch-inactive-parallel-segments'
-import { revalidateEntireCache } from '../../segment-cache'
+import { revalidateEntireCache } from '../../segment-cache/cache'
 
 export function refreshReducer(
   state: ReadonlyReducerState,

packages/next/src/client/components/router-reducer/reducers/server-action-reducer.ts

@@ -55,7 +55,7 @@ import {
   extractInfoFromServerReferenceId,
   omitUnusedArgs,
 } from '../../../../shared/lib/server-reference-info'
-import { revalidateEntireCache } from '../../segment-cache'
+import { revalidateEntireCache } from '../../segment-cache/cache'
 
 const createFromFetch =
   createFromFetchBrowser as (typeof import('react-server-dom-webpack/client.browser'))['createFromFetch']

packages/next/src/client/components/segment-cache-impl/cache.ts → packages/next/src/client/components/segment-cache/cache.ts

@@ -93,9 +93,17 @@ import {
   DOC_PREFETCH_RANGE_HEADER_VALUE,
   doesExportedHtmlMatchBuildId,
 } from '../../../shared/lib/segment-cache/output-export-prefetch-encoding'
-import { FetchStrategy, getStaleTimeMs } from '../segment-cache'
+import { FetchStrategy } from './types'
 import { createPromiseWithResolvers } from '../../../shared/lib/promise-with-resolvers'
 
+/**
+ * Ensures a minimum stale time of 30s to avoid issues where the server sends a too
+ * short-lived stale time, which would prevent anything from being prefetched.
+ */
+export function getStaleTimeMs(staleTimeSeconds: number): number {
+  return Math.max(staleTimeSeconds, 30) * 1000
+}
+
 // A note on async/await when working in the prefetch cache:
 //
 // Most async operations in the prefetch cache should *not* use async/await,

packages/next/src/client/components/segment-cache-impl/navigation.ts → packages/next/src/client/components/segment-cache/navigation.ts

@@ -28,7 +28,7 @@ import {
 } from './cache'
 import { createCacheKey } from './cache-key'
 import { addSearchParamsIfPageSegment } from '../../../shared/lib/segment'
-import { NavigationResultTag } from '../segment-cache'
+import { NavigationResultTag } from './types'
 
 type MPANavigationResult = {
   tag: NavigationResultTag.MPA

packages/next/src/client/components/segment-cache-impl/prefetch.ts → packages/next/src/client/components/segment-cache/prefetch.ts

@@ -2,10 +2,7 @@ import type { FlightRouterState } from '../../../shared/lib/app-router-types'
 import { createPrefetchURL } from '../app-router-utils'
 import { createCacheKey } from './cache-key'
 import { schedulePrefetchTask } from './scheduler'
-import {
-  PrefetchPriority,
-  type PrefetchTaskFetchStrategy,
-} from '../segment-cache'
+import { PrefetchPriority, type PrefetchTaskFetchStrategy } from './types'
 
 /**
  * Entrypoint for prefetching a URL into the Segment Cache.

packages/next/src/client/components/segment-cache-impl/scheduler.ts → packages/next/src/client/components/segment-cache/scheduler.ts

@@ -33,9 +33,9 @@ import { createCacheKey } from './cache-key'
 import {
   FetchStrategy,
   type PrefetchTaskFetchStrategy,
-  getCurrentCacheVersion,
   PrefetchPriority,
-} from '../segment-cache'
+} from './types'
+import { getCurrentCacheVersion } from './cache'
 import {
   addSearchParamsIfPageSegment,
   PAGE_SEGMENT_KEY,

packages/next/src/client/components/segment-cache/types.ts

@@ -0,0 +1,53 @@
+/**
+ * Shared types and constants for the Segment Cache.
+ */
+
+export const enum NavigationResultTag {
+  MPA,
+  Success,
+  NoOp,
+  Async,
+}
+
+/**
+ * The priority of the prefetch task. Higher numbers are higher priority.
+ */
+export const enum PrefetchPriority {
+  /**
+   * Assigned to the most recently hovered/touched link. Special network
+   * bandwidth is reserved for this task only. There's only ever one Intent-
+   * priority task at a time; when a new Intent task is scheduled, the previous
+   * one is bumped down to Default.
+   */
+  Intent = 2,
+  /**
+   * The default priority for prefetch tasks.
+   */
+  Default = 1,
+  /**
+   * Assigned to tasks when they spawn non-blocking background work, like
+   * revalidating a partially cached entry to see if more data is available.
+   */
+  Background = 0,
+}
+
+export const enum FetchStrategy {
+  // Deliberately ordered so we can easily compare two segments
+  // and determine if one segment is "more specific" than another
+  // (i.e. if it's likely that it contains more data)
+  LoadingBoundary = 0,
+  PPR = 1,
+  PPRRuntime = 2,
+  Full = 3,
+}
+
+/**
+ * A subset of fetch strategies used for prefetch tasks.
+ * A prefetch task can't know if it should use `PPR` or `LoadingBoundary`
+ * until we complete the initial tree prefetch request, so we use `PPR` to signal both cases
+ * and adjust it based on the route when actually fetching.
+ * */
+export type PrefetchTaskFetchStrategy =
+  | FetchStrategy.PPR
+  | FetchStrategy.PPRRuntime
+  | FetchStrategy.Full

packages/next/src/client/flight-data-helpers.ts

@@ -9,7 +9,7 @@ import type {
   InitialRSCPayload,
 } from '../shared/lib/app-router-types'
 import { PAGE_SEGMENT_KEY } from '../shared/lib/segment'
-import type { NormalizedSearch } from './components/segment-cache'
+import type { NormalizedSearch } from './components/segment-cache/cache-key'
 import {
   getCacheKeyForDynamicParam,
   parseDynamicParamFromURLPart,

packages/next/src/client/route-params.ts

@@ -13,7 +13,7 @@ import {
 import type {
   NormalizedPathname,
   NormalizedSearch,
-} from './components/segment-cache'
+} from './components/segment-cache/cache-key'
 import type { RSCResponse } from './components/router-reducer/fetch-server-response'
 import type { ParsedUrlQuery } from 'querystring'
 

packages/next/src/shared/lib/segment-cache/segment-value-encoding.ts

@@ -1,6 +1,6 @@
 import { PAGE_SEGMENT_KEY } from '../segment'
 import type { Segment as FlightRouterStateSegment } from '../app-router-types'
-import type { NormalizedPathname } from '../../../client/components/segment-cache'
+import type { NormalizedPathname } from '../../../client/components/segment-cache/cache-key'
 
 // TypeScript trick to simulate opaque types, like in Flow.
 type Opaque<K, T> = T & { __brand: K }