Ensure we don't poll page in development when notFound: true is returned

packages/next/client/dev/on-demand-entries-client.js

@@ -11,7 +11,17 @@ export default async (page) => {
   } else {
     Router.ready(() => {
       setInterval(() => {
-        sendMessage(JSON.stringify({ event: 'ping', page: Router.pathname }))
+        // when notFound: true is returned we should use the notFoundPage
+        // as the Router.pathname will point to the 404 page but we want
+        // to ping the source page that returned notFound: true instead
+        const notFoundSrcPage = self.__NEXT_DATA__.notFoundSrcPage
+        const pathname =
+          (Router.pathname === '/404' || Router.pathname === '/_error') &&
+          notFoundSrcPage
+            ? notFoundSrcPage
+            : Router.pathname
+
+        sendMessage(JSON.stringify({ event: 'ping', page: pathname }))
       }, 2500)
     })
   }

packages/next/server/base-server.ts

@@ -1550,6 +1550,9 @@ export default abstract class Server {
         res.body('{"notFound":true}').send()
         return null
       } else {
+        if (this.renderOpts.dev) {
+          query.__nextNotFoundSrcPage = pathname
+        }
         await this.render404(
           req,
           res,

packages/next/server/render.tsx

@@ -528,9 +528,11 @@ export async function renderToHTML(
   const headTags = (...args: any) => callMiddleware('headTags', args)
 
   const isFallback = !!query.__nextFallback
+  const notFoundSrcPage = query.__nextNotFoundSrcPage
   delete query.__nextFallback
   delete query.__nextLocale
   delete query.__nextDefaultLocale
+  delete query.__nextIsNotFound
 
   const isSSG = !!getStaticProps
   const isBuildTimeSSG = isSSG && renderOpts.nextExport
@@ -1374,6 +1376,7 @@ export async function renderToHTML(
       defaultLocale,
       domainLocales,
       isPreview: isPreview === true ? true : undefined,
+      notFoundSrcPage: notFoundSrcPage && dev ? notFoundSrcPage : undefined,
     },
     buildManifest: filteredBuildManifest,
     docComponentsRendered,

packages/next/server/request-meta.ts

@@ -53,6 +53,7 @@ export function addRequestMeta<K extends keyof RequestMeta>(
 }
 
 type NextQueryMetadata = {
+  __nextNotFoundSrcPage?: string
   __nextDefaultLocale?: string
   __nextFallback?: 'true'
   __nextLocale?: string

packages/next/shared/lib/utils.ts

@@ -107,6 +107,7 @@ export type NEXT_DATA = {
   domainLocales?: DomainLocale[]
   scriptLoader?: any[]
   isPreview?: boolean
+  notFoundSrcPage?: string
   rsc?: boolean
 }
 

test/development/gssp-notfound/index.test.ts

@@ -0,0 +1,34 @@
+import { createNext } from 'e2e-utils'
+import { NextInstance } from 'test/lib/next-modes/base'
+import { waitFor } from 'next-test-utils'
+import webdriver from 'next-webdriver'
+
+describe('getServerSideProps returns notFound: true', () => {
+  let next: NextInstance
+
+  beforeAll(async () => {
+    next = await createNext({
+      files: {
+        'pages/index.js': `
+        const Home = () => null
+        export default Home
+
+        export function getServerSideProps() {
+          console.log("gssp called")
+          return { notFound: true }
+        }
+        `,
+      },
+      dependencies: {},
+    })
+  })
+  afterAll(() => next.destroy())
+
+  it('should not poll indefinitely', async () => {
+    const browser = await webdriver(next.appPort, '/')
+    await waitFor(3000)
+    await browser.close()
+    const logOccurrences = next.cliOutput.split('gssp called').length - 1
+    expect(logOccurrences).toBe(1)
+  })
+})