[dynamicIO] update controller to be non-optional (vercel#72048)

Previously we used the controller a signal for whether the current
dynamicIO prerender should abort early or not. Now we separate the
controller which signals whether we've left the Prerneder phase from the
signal that actually aborts the render in some cases. Now we can always
scope a controller in the prerenderStore and depending on whether we are
filling caches or not we will end the render early or let it continue.

With this change the controller is always provided so we can reflect
this in the type

packages/next/src/server/app-render/dynamic-rendering.ts

@@ -265,9 +265,7 @@ function abortOnSynchronousDynamicDataAccess(
 
   const error = createPrerenderInterruptedError(reason)
 
-  if (prerenderStore.controller) {
-    prerenderStore.controller.abort(error)
-  }
+  prerenderStore.controller.abort(error)
 
   const dynamicTracking = prerenderStore.dynamicTracking
   if (dynamicTracking) {

packages/next/src/server/app-render/work-unit-async-storage.external.ts

@@ -67,23 +67,25 @@ export type RequestStore = {
 export type PrerenderStoreModern = {
   type: 'prerender'
   readonly implicitTags: string[]
+
+  /**
+   * This signal is aborted when the React render is complete. (i.e. it is the same signal passed to react)
+   */
+  readonly renderSignal: AbortSignal
   /**
-   * This is the AbortController passed to React. It can be used to abort the prerender
-   * if we encounter conditions that do not require further rendering
+   * This is the AbortController which represents the boundary between Prerender and dynamic. In some renders it is
+   * the same as the controller for the renderSignal but in others it is a separate controller. It should be aborted
+   * whenever the we are no longer in the prerender phase of rendering. Typically this is after one task or when you call
+   * a sync API which requires the prerender to end immediately
    */
-  readonly controller: null | AbortController
+  readonly controller: AbortController
 
   /**
    * when not null this signal is used to track cache reads during prerendering and
    * to await all cache reads completing before aborting the prerender.
    */
   readonly cacheSignal: null | CacheSignal
 
-  /**
-   * This signal is used to clean up the prerender once it is complete.
-   */
-  readonly renderSignal: AbortSignal
-
   /**
    * During some prerenders we want to track dynamic access.
    */

packages/next/src/server/route-modules/app-route/module.ts

@@ -61,7 +61,6 @@ import {
   postponeWithTracking,
   createDynamicTrackingState,
   getFirstDynamicReason,
-  isPrerenderInterruptedError,
 } from '../../app-render/dynamic-rendering'
 import { ReflectAdapter } from '../../web/spec-extension/adapters/reflect'
 import type { RenderOptsPartial } from '../../app-render/types'
@@ -349,10 +348,10 @@ export class AppRouteRouteModule extends RouteModule<
               phase: 'action',
               implicitTags: implicitTags,
               renderSignal: prospectiveController.signal,
+              controller: prospectiveController,
               cacheSignal,
               // During prospective render we don't use a controller
               // because we need to let all caches fill.
-              controller: null,
               dynamicTracking,
               revalidate: defaultRevalidate,
               expire: INFINITE_CACHE,
@@ -369,11 +368,14 @@ export class AppRouteRouteModule extends RouteModule<
               handlerContext
             )
           } catch (err) {
-            if (isPrerenderInterruptedError(err)) {
+            if (prospectiveController.signal.aborted) {
               // the route handler called an API which is always dynamic
               // there is no need to try again
               prospectiveRenderIsDynamic = true
-            } else if (process.env.NEXT_DEBUG_BUILD) {
+            } else if (
+              process.env.NEXT_DEBUG_BUILD ||
+              process.env.__NEXT_VERBOSE_LOGGING
+            ) {
               printDebugThrownValueForProspectiveRender(err, workStore.route)
             }
           }
@@ -387,7 +389,7 @@ export class AppRouteRouteModule extends RouteModule<
             ;(prospectiveResult as any as Promise<unknown>).then(
               () => {},
               (err) => {
-                if (isPrerenderInterruptedError(err)) {
+                if (prospectiveController.signal.aborted) {
                   // the route handler called an API which is always dynamic
                   // there is no need to try again
                   prospectiveRenderIsDynamic = true
@@ -431,8 +433,8 @@ export class AppRouteRouteModule extends RouteModule<
             phase: 'action',
             implicitTags: implicitTags,
             renderSignal: finalController.signal,
-            cacheSignal: null,
             controller: finalController,
+            cacheSignal: null,
             dynamicTracking,
             revalidate: defaultRevalidate,
             expire: INFINITE_CACHE,