if there are errors during postpone, or postpone was caught, fail static generation

packages/next/src/export/routes/app-page.ts

@@ -13,7 +13,6 @@ import {
   NEXT_URL,
   NEXT_ROUTER_PREFETCH,
 } from '../../client/components/app-router-headers'
-import { isDynamicUsageError } from '../helpers/is-dynamic-usage-error'
 import { NEXT_CACHE_TAGS_HEADER } from '../../lib/constants'
 import { hasNextSupport } from '../../telemetry/ci-info'
 import { lazyRenderAppPage } from '../../server/future/route-modules/app-page/module.render'
@@ -80,8 +79,35 @@ export async function exportAppPage(
     pathname = '/404'
   }
 
-  try {
-    if (isAppPrefetch) {
+  if (isAppPrefetch) {
+    await generatePrefetchRsc(
+      req,
+      path,
+      res,
+      pathname,
+      htmlFilepath,
+      renderOpts,
+      fileWriter
+    )
+
+    return { revalidate: 0 }
+  }
+
+  const result = await lazyRenderAppPage(req, res, pathname, query, renderOpts)
+  const html = result.toUnchunkedString()
+  const { metadata } = result
+  const flightData = metadata.pageData
+  const revalidate = metadata.revalidate ?? false
+  const postponed = metadata.postponed
+
+  if (revalidate === 0) {
+    if (isDynamicError) {
+      throw new Error(
+        `Page with dynamic = "error" encountered dynamic data method on ${path}.`
+      )
+    }
+
+    if (!(renderOpts as any).store.staticPrefetchBailout) {
       await generatePrefetchRsc(
         req,
         path,
@@ -91,109 +117,60 @@ export async function exportAppPage(
         renderOpts,
         fileWriter
       )
-
-      return { revalidate: 0 }
     }
 
-    const result = await lazyRenderAppPage(
-      req,
-      res,
-      pathname,
-      query,
-      renderOpts
-    )
-    const html = result.toUnchunkedString()
-    const { metadata } = result
-    const flightData = metadata.pageData
-    const revalidate = metadata.revalidate ?? false
-    const postponed = metadata.postponed
-
-    if (revalidate === 0) {
-      if (isDynamicError) {
-        throw new Error(
-          `Page with dynamic = "error" encountered dynamic data method on ${path}.`
-        )
-      }
-
-      if (!(renderOpts as any).store.staticPrefetchBailout) {
-        await generatePrefetchRsc(
-          req,
-          path,
-          res,
-          pathname,
-          htmlFilepath,
-          renderOpts,
-          fileWriter
-        )
-      }
-
-      const { staticBailoutInfo = {} } = metadata
-
-      if (revalidate === 0 && debugOutput && staticBailoutInfo?.description) {
-        const err = new Error(
-          `Static generation failed due to dynamic usage on ${path}, reason: ${staticBailoutInfo.description}`
-        )
+    const { staticBailoutInfo = {} } = metadata
 
-        // Update the stack if it was provided via the bailout info.
-        const { stack } = staticBailoutInfo
-        if (stack) {
-          err.stack = err.message + stack.substring(stack.indexOf('\n'))
-        }
+    if (revalidate === 0 && debugOutput && staticBailoutInfo?.description) {
+      const err = new Error(
+        `Static generation failed due to dynamic usage on ${path}, reason: ${staticBailoutInfo.description}`
+      )
 
-        console.warn(err)
+      // Update the stack if it was provided via the bailout info.
+      const { stack } = staticBailoutInfo
+      if (stack) {
+        err.stack = err.message + stack.substring(stack.indexOf('\n'))
       }
 
-      return { revalidate: 0 }
+      console.warn(err)
     }
 
-    let headers: OutgoingHttpHeaders | undefined
-    if (metadata.fetchTags) {
-      headers = { [NEXT_CACHE_TAGS_HEADER]: metadata.fetchTags }
-    }
+    return { revalidate: 0 }
+  }
 
-    // Writing static HTML to a file.
-    await fileWriter(
-      ExportedAppPageFiles.HTML,
-      htmlFilepath,
-      html ?? '',
-      'utf8'
-    )
+  let headers: OutgoingHttpHeaders | undefined
+  if (metadata.fetchTags) {
+    headers = { [NEXT_CACHE_TAGS_HEADER]: metadata.fetchTags }
+  }
 
-    // Writing the request metadata to a file.
-    const meta: RouteMetadata = {
-      status: undefined,
-      headers,
-      postponed,
-    }
+  // Writing static HTML to a file.
+  await fileWriter(ExportedAppPageFiles.HTML, htmlFilepath, html ?? '', 'utf8')
 
-    await fileWriter(
-      ExportedAppPageFiles.META,
-      htmlFilepath.replace(/\.html$/, '.meta'),
-      JSON.stringify(meta, null, 2)
-    )
+  // Writing the request metadata to a file.
+  const meta: RouteMetadata = {
+    status: undefined,
+    headers,
+    postponed,
+  }
 
-    // Writing the RSC payload to a file.
-    await fileWriter(
-      ExportedAppPageFiles.FLIGHT,
-      htmlFilepath.replace(/\.html$/, '.rsc'),
-      flightData
-    )
+  await fileWriter(
+    ExportedAppPageFiles.META,
+    htmlFilepath.replace(/\.html$/, '.meta'),
+    JSON.stringify(meta, null, 2)
+  )
 
-    return {
-      // Only include the metadata if the environment has next support.
-      metadata: hasNextSupport ? meta : undefined,
-      hasEmptyPrelude: Boolean(postponed) && html === '',
-      hasPostponed: Boolean(postponed),
-      revalidate,
-    }
-  } catch (err: any) {
-    // if the error isn't a special dynamic usage error (caught by Next)
-    // we also do not throw the error if it occurred while attempting a postpone
-    // since those will be captured and logged during build/ISR
-    if (!isDynamicUsageError(err) && !renderOpts.hasPostponeErrors) {
-      throw err
-    }
+  // Writing the RSC payload to a file.
+  await fileWriter(
+    ExportedAppPageFiles.FLIGHT,
+    htmlFilepath.replace(/\.html$/, '.rsc'),
+    flightData
+  )
 
-    return { revalidate: 0, hasEmptyPrelude: true }
+  return {
+    // Only include the metadata if the environment has next support.
+    metadata: hasNextSupport ? meta : undefined,
+    hasEmptyPrelude: Boolean(postponed) && html === '',
+    hasPostponed: Boolean(postponed),
+    revalidate,
   }
 }

packages/next/src/export/routes/app-route.ts

@@ -16,7 +16,7 @@ import type {
   MockedRequest,
   MockedResponse,
 } from '../../server/lib/mock-request'
-import { isDynamicUsageError } from '../helpers/is-dynamic-usage-error'
+import { isDynamicUsageError } from '../../server/app-render/is-dynamic-usage-error'
 import { SERVER_DIRECTORY } from '../../shared/lib/constants'
 import { hasNextSupport } from '../../telemetry/ci-info'
 

packages/next/src/server/app-render/app-render.tsx

@@ -61,7 +61,7 @@ import { validateURL } from './validate-url'
 import { createFlightRouterStateFromLoaderTree } from './create-flight-router-state-from-loader-tree'
 import { handleAction } from './action-handler'
 import { NEXT_DYNAMIC_NO_SSR_CODE } from '../../shared/lib/lazy-dynamic/no-ssr-error'
-import { warn, error } from '../../build/output/log'
+import { warn } from '../../build/output/log'
 import { appendMutableCookies } from '../web/spec-extension/adapters/request-cookies'
 import { createServerInsertedHTML } from './server-inserted-html'
 import { getRequiredScripts } from './required-scripts'
@@ -72,6 +72,8 @@ import { createComponentTree } from './create-component-tree'
 import { getAssetQueryString } from './get-asset-query-string'
 import { setReferenceManifestsSingleton } from './action-encryption-utils'
 import { createStaticRenderer } from './static/static-renderer'
+import { isPostpone } from '../lib/router-utils/is-postpone'
+import { isDynamicUsageError } from './is-dynamic-usage-error'
 
 export type GetDynamicParamFromSegment = (
   // [slug] / [[slug]] / [...slug]
@@ -999,33 +1001,24 @@ async function renderToHTMLOrFlightImpl(
   if (staticGenerationStore.isStaticGeneration) {
     const htmlResult = await renderResult.toUnchunkedString(true)
 
-    if (renderOpts.ppr && postponeErrors.length > 0) {
-      renderOpts.hasPostponeErrors = true
-    }
-
     if (
       renderOpts.ppr &&
       staticGenerationStore.postponeWasTriggered &&
       !extraRenderResultMeta.postponed
     ) {
-      warn('')
-      warn(
-        `${urlPathname} opted out of partial prerendering because the postpone signal was intercepted by a try/catch in your application code.`
+      throw new Error(
+        `Postpone signal was caught while rendering ${urlPathname}. These errors should not be caught during static generation. Learn more: https://nextjs.org/docs/messages/ppr-postpone-errors`
       )
+    }
 
-      if (postponeErrors.length > 0) {
-        warn(
-          'The following errors were re-thrown, and might help find the location of the try/catch that triggered this.'
-        )
-        for (let i = 0; i < postponeErrors.length; i++) {
-          error(`${postponeErrors[i].stack?.split('\n').join('\n ')}`)
-        }
+    for (const err of capturedErrors) {
+      if (!isDynamicUsageError(err) && !isPostpone(err)) {
+        throw err
+      }
+
+      if (isDynamicUsageError(err)) {
+        staticGenerationStore.revalidate = 0
       }
-    }
-    // if we encountered any unexpected errors during build
-    // we fail the prerendering phase and the build
-    if (capturedErrors.length > 0) {
-      throw capturedErrors[0]
     }
 
     if (staticGenerationStore.forceStatic === false) {

packages/next/src/server/app-render/types.ts

@@ -137,7 +137,6 @@ export interface RenderOptsPartial {
   isPrefetch?: boolean
   ppr: boolean
   postponed?: string
-  hasPostponeErrors?: boolean
 }
 
 export type RenderOpts = LoadComponentsReturnType<AppPageModule> &

test/e2e/app-dir/ppr-errors/app/layout.jsx

@@ -0,0 +1,9 @@
+import React from 'react'
+
+export default function Root({ children }) {
+  return (
+    <html>
+      <body>{children}</body>
+    </html>
+  )
+}

test/e2e/app-dir/ppr/app/suspense/node/cookies-error-no-throw/page.jsx → test/e2e/app-dir/ppr-errors/app/page.jsx

@@ -7,7 +7,7 @@ export default async function Page() {
       <h2>Dynamic Component Catching Errors</h2>
       <p>
         This shows the dynamic component that reads cookies but wraps the read
-        in a try/catch. This test does not re-throw the caught error.
+        in a try/catch.
       </p>
       <div id="container">
         <Suspense fallback={<div>Loading...</div>}>

test/e2e/app-dir/ppr-errors/next.config.js

@@ -0,0 +1,10 @@
+/**
+ * @type {import('next').NextConfig}
+ */
+const nextConfig = {
+  experimental: {
+    ppr: true,
+  },
+}
+
+module.exports = nextConfig

test/e2e/app-dir/ppr-errors/ppr.test.ts

@@ -0,0 +1,10 @@
+import { nextBuild } from 'next-test-utils'
+
+describe('ppr build errors', () => {
+  it('should fail the build', async () => {
+    const out = await nextBuild(__dirname, [], { stderr: true })
+    expect(out.stderr).toContain(
+      'Postpone signal was caught while rendering /. These errors should not be caught during static generation.'
+    )
+  })
+})