From 4c94a858eb9698e5d989a94b3883877c64beca58 Mon Sep 17 00:00:00 2001
From: Jiachi Liu <inbox@huozhi.im>
Date: Fri, 12 Nov 2021 01:47:40 +0100
Subject: [PATCH] 500 page

---
 packages/next/build/entries.ts                |  2 +-
 .../next-middleware-ssr-loader/index.ts       | 20 ++++++++++++-------
 .../app/pages/err.js                          |  5 +++++
 .../test/index.test.js                        |  2 ++
 4 files changed, 21 insertions(+), 8 deletions(-)
 create mode 100644 test/integration/react-streaming-and-server-components/app/pages/err.js

diff --git a/packages/next/build/entries.ts b/packages/next/build/entries.ts
index 42492d511d85354..a4b97bc00bd4544 100644
--- a/packages/next/build/entries.ts
+++ b/packages/next/build/entries.ts
@@ -162,7 +162,7 @@ export function createEntrypoints(
           page,
           absoluteAppPath: pages['/_app'],
           absoluteDocumentPath: pages['/_document'],
-          absoluteErrorPath: pages['/500'] || pages['/_error'],
+          absoluteErrorPath: pages['/_error'],
           absolutePagePath,
           isServerComponent: isFlight,
           buildId,
diff --git a/packages/next/build/webpack/loaders/next-middleware-ssr-loader/index.ts b/packages/next/build/webpack/loaders/next-middleware-ssr-loader/index.ts
index 810569b6ecd63bf..8f2144e22e4b987 100644
--- a/packages/next/build/webpack/loaders/next-middleware-ssr-loader/index.ts
+++ b/packages/next/build/webpack/loaders/next-middleware-ssr-loader/index.ts
@@ -16,15 +16,12 @@ export default async function middlewareRSCLoader(this: any) {
   const stringifiedAbsolutePagePath = stringifyRequest(this, absolutePagePath)
   const stringifiedAbsoluteAppPath = stringifyRequest(this, absoluteAppPath)
   const stringifiedAbsoluteErrorPath = stringifyRequest(this, absoluteErrorPath)
+  const stringified500PagePath = stringifyRequest(this, './pages/500')
   const stringifiedAbsoluteDocumentPath = stringifyRequest(
     this,
     absoluteDocumentPath
   )
 
-  const appDefinition = `const App = require(${stringifiedAbsoluteAppPath}).default`
-  const documentDefinition = `const Document = require(${stringifiedAbsoluteDocumentPath}).default`
-  const errorDefinition = `const ErrorPage = require(${stringifiedAbsoluteErrorPath}).default`
-
   const transformed = `
         import { adapter } from 'next/dist/server/web/adapter'
 
@@ -41,9 +38,18 @@ export default async function middlewareRSCLoader(this: any) {
             : ''
         }
 
-        ${appDefinition}
-        ${documentDefinition}
-        ${errorDefinition}
+        import App from ${stringifiedAbsoluteAppPath}
+        import Document from ${stringifiedAbsoluteDocumentPath}
+
+
+        let ErrorPage
+        try {
+          ErrorPage = require(${stringified500PagePath}).default
+        } catch (_) {
+          ErrorPage = require(${stringifiedAbsoluteErrorPath}).default
+        }
+
+        // import ErrorPage from ${stringifiedAbsoluteErrorPath}
         
         const {
           default: Page,
diff --git a/test/integration/react-streaming-and-server-components/app/pages/err.js b/test/integration/react-streaming-and-server-components/app/pages/err.js
new file mode 100644
index 000000000000000..61c7136f7ba7e48
--- /dev/null
+++ b/test/integration/react-streaming-and-server-components/app/pages/err.js
@@ -0,0 +1,5 @@
+const page = () => 'page with err'
+page.getInitialProps = () => {
+  throw new Error('oops')
+}
+export default page
diff --git a/test/integration/react-streaming-and-server-components/test/index.test.js b/test/integration/react-streaming-and-server-components/test/index.test.js
index d0d26c4671a1867..5bd7d097e78b36e 100644
--- a/test/integration/react-streaming-and-server-components/test/index.test.js
+++ b/test/integration/react-streaming-and-server-components/test/index.test.js
@@ -217,6 +217,7 @@ async function runBasicTests(context) {
     )
 
     const path404HTML = await renderViaHTTP(context.appPort, '/404')
+    const path500HTML = await renderViaHTTP(context.appPort, '/err')
     const pathNotFoundHTML = await renderViaHTTP(
       context.appPort,
       '/this-is-not-found'
@@ -230,6 +231,7 @@ async function runBasicTests(context) {
     expect(dynamicRouteHTML2).toContain('[pid]')
 
     expect(path404HTML).toContain('custom-404-page')
+    expect(path500HTML).toContain('custom-500-page')
     expect(pathNotFoundHTML).toContain('custom-404-page')
   })