Create hash digest for errors in app in production (vercel#41559)

packages/next/server/app-render.tsx

@@ -42,6 +42,7 @@ import { DYNAMIC_ERROR_CODE } from '../client/components/hooks-server-context'
 import { NOT_FOUND_ERROR_CODE } from '../client/components/not-found'
 import { HeadManagerContext } from '../shared/lib/head-manager-context'
 import { Writable } from 'stream'
+import stringHash from 'next/dist/compiled/string-hash'
 
 const INTERNAL_HEADERS_INSTANCE = Symbol('internal for headers readonly')
 
@@ -176,21 +177,21 @@ function createErrorHandler(
   _source: string,
   capturedErrors: Error[]
 ) {
-  return (err: any) => {
+  return (err: any): string => {
     if (
-      // TODO-APP: Handle redirect throw
-      err.digest !== DYNAMIC_ERROR_CODE &&
-      err.digest !== NOT_FOUND_ERROR_CODE &&
-      !err.digest?.startsWith(REDIRECT_ERROR_CODE)
+      err.digest === DYNAMIC_ERROR_CODE ||
+      err.digest === NOT_FOUND_ERROR_CODE ||
+      err.digest?.startsWith(REDIRECT_ERROR_CODE)
     ) {
-      // Used for debugging error source
-      // console.error(_source, err)
-      console.error(err)
-      capturedErrors.push(err)
-      return err.digest || err.message
+      return err.digest
     }
 
-    return err.digest
+    // Used for debugging error source
+    // console.error(_source, err)
+    console.error(err)
+    capturedErrors.push(err)
+    // TODO-APP: look at using webcrypto instead. Requires a promise to be awaited.
+    return stringHash(err.message + err.stack + (err.digest || '')).toString()
   }
 }
 

test/e2e/app-dir/app/app/error/server-component/custom-digest/page.js

@@ -0,0 +1,9 @@
+export const config = {
+  revalidate: 0,
+}
+
+export default function Page() {
+  const err = new Error('this is a test')
+  err.digest = 'custom'
+  throw err
+}

test/e2e/app-dir/app/app/error/server-component/error.js

@@ -0,0 +1,13 @@
+'use client'
+
+export default function ErrorBoundary({ error, reset }) {
+  return (
+    <>
+      <p id="error-boundary-message">{error.message}</p>
+      <p id="error-boundary-digest">{error.digest}</p>
+      <button id="reset" onClick={() => reset()}>
+        Try again
+      </button>
+    </>
+  )
+}

test/e2e/app-dir/app/app/error/server-component/page.js

@@ -0,0 +1,7 @@
+export const config = {
+  revalidate: 0,
+}
+
+export default function Page() {
+  throw new Error('this is a test')
+}

test/e2e/app-dir/index.test.ts

@@ -1553,8 +1553,7 @@ describe('app dir', () => {
 
         if (isDev) {
           expect(await hasRedbox(browser)).toBe(true)
-          console.log('getRedboxHeader', await getRedboxHeader(browser))
-          // expect(await getRedboxHeader(browser)).toMatch(/An error occurred: this is a test/)
+          expect(await getRedboxHeader(browser)).toMatch(/this is a test/)
         } else {
           await browser
           expect(
@@ -1566,6 +1565,37 @@ describe('app dir', () => {
         }
       })
 
+      it('should trigger error component when an error happens during server components rendering', async () => {
+        const browser = await webdriver(next.url, '/error/server-component')
+
+        if (isDev) {
+          expect(
+            await browser
+              .waitForElementByCss('#error-boundary-message')
+              .elementByCss('#error-boundary-message')
+              .text()
+          ).toBe('this is a test')
+          expect(
+            await browser.waitForElementByCss('#error-boundary-digest').text()
+            // Digest of the error message should be stable.
+          ).not.toBe('')
+          // TODO-APP: ensure error overlay is shown for errors that happened before/during hydration
+          // expect(await hasRedbox(browser)).toBe(true)
+          // expect(await getRedboxHeader(browser)).toMatch(/this is a test/)
+        } else {
+          await browser
+          expect(
+            await browser.waitForElementByCss('#error-boundary-message').text()
+          ).toBe(
+            'An error occurred in the Server Components render. The specific message is omitted in production builds to avoid leaking sensitive details. A digest property is included on this error instance which may provide additional details about the nature of the error.'
+          )
+          expect(
+            await browser.waitForElementByCss('#error-boundary-digest').text()
+            // Digest of the error message should be stable.
+          ).not.toBe('')
+        }
+      })
+
       it('should use default error boundary for prod and overlay for dev when no error component specified', async () => {
         const browser = await webdriver(
           next.url,