Fix metadata prop merging (#69807)

### What Fixes metadata merging issue on 14.2. There's a bug with React on 14.2 as it bit outdated: while generating rsc payload, if we use fragment to wrap the metadata and noindex component, it will miss all the data. It works well with separating them as an array. It also requires #64058 to be applied as well so the output not-found page will having correct status 404, and then we can generate noindex metatag based on correct status Fixes #69778
vercel · Sep 9, 2024 · 747d365 · 747d365
1 parent 196dab6
commit 747d365
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Showing 10 changed files with 120 additions and 8 deletions.
diff --git a/packages/next/src/server/app-render/app-render.tsx b/packages/next/src/server/app-render/app-render.tsx
@@ -319,13 +319,11 @@ async function generateFlight(
         flightRouterState,
         isFirst: true,
         // For flight, render metadata inside leaf page
-        rscPayloadHead: (
-          <>
-            <NonIndex ctx={ctx} />
-            {/* Adding requestId as react key to make metadata remount for each render */}
-            <MetadataTree key={requestId} />
-          </>
-        ),
+        // NOTE: in 14.2, fragment doesn't work well with React, using array instead
+        rscPayloadHead: [
+          <MetadataTree key={requestId} />,
+          <NonIndex key="noindex" ctx={ctx} />,
+        ],
         injectedCSS: new Set(),
         injectedJS: new Set(),
         injectedFontPreloadTags: new Set(),
@@ -531,12 +529,12 @@ async function ReactServerError({
 
   const head = (
     <>
-      <NonIndex ctx={ctx} />
       {/* Adding requestId as react key to make metadata remount for each render */}
       <MetadataTree key={requestId} />
       {process.env.NODE_ENV === 'development' && (
         <meta name="next-error" content="not-found" />
       )}
+      <NonIndex ctx={ctx} />
     </>
   )
 

diff --git a/test/e2e/app-dir/metadata-navigation/app/(cart)/product/layout.tsx b/test/e2e/app-dir/metadata-navigation/app/(cart)/product/layout.tsx
@@ -0,0 +1,13 @@
+import { Metadata } from 'next'
+
+export const metadata: Metadata = {
+  title: 'Product Layout',
+}
+
+export default function Layout({
+  children,
+}: Readonly<{
+  children: React.ReactNode
+}>) {
+  return <>{children}</>
+}
diff --git a/test/e2e/app-dir/metadata-navigation/app/(cart)/product/page.tsx b/test/e2e/app-dir/metadata-navigation/app/(cart)/product/page.tsx
@@ -0,0 +1,3 @@
+export default function Page() {
+  return <div>Product page content</div>
+}
diff --git a/test/e2e/app-dir/metadata-navigation/app/@header/layout.tsx b/test/e2e/app-dir/metadata-navigation/app/@header/layout.tsx
@@ -0,0 +1,7 @@
+type LayoutProps = {
+  children: React.ReactNode
+}
+
+export default function Layout({ children }: LayoutProps) {
+  return <div>{children}</div>
+}
diff --git a/test/e2e/app-dir/metadata-navigation/app/@header/page.tsx b/test/e2e/app-dir/metadata-navigation/app/@header/page.tsx
@@ -0,0 +1,12 @@
+import Link from 'next/link'
+
+export default function Page() {
+  return (
+    <div>
+      <div>Home header</div>
+      <Link href="/product" id="product-link">
+        Product
+      </Link>
+    </div>
+  )
+}
diff --git a/test/e2e/app-dir/metadata-navigation/app/@header/product/layout.tsx b/test/e2e/app-dir/metadata-navigation/app/@header/product/layout.tsx
@@ -0,0 +1,7 @@
+type LayoutProps = {
+  children: React.ReactNode
+}
+
+export default function Layout({ children }: LayoutProps) {
+  return <>{children}</>
+}
diff --git a/test/e2e/app-dir/metadata-navigation/app/@header/product/page.tsx b/test/e2e/app-dir/metadata-navigation/app/@header/product/page.tsx
@@ -0,0 +1,12 @@
+import Link from 'next/link'
+
+export default function Page() {
+  return (
+    <div>
+      <h1 id="product-title">Product header</h1>
+      <Link href="/" id="home-link">
+        Go to Home page
+      </Link>
+    </div>
+  )
+}
diff --git a/test/e2e/app-dir/metadata-navigation/app/layout.tsx b/test/e2e/app-dir/metadata-navigation/app/layout.tsx
@@ -0,0 +1,23 @@
+import type { Metadata } from 'next'
+
+export const metadata: Metadata = {
+  title: 'Home Layout',
+  description: 'Generated by create next app',
+}
+
+export default function RootLayout({
+  header,
+  children,
+}: Readonly<{
+  header: React.ReactNode
+  children: React.ReactNode
+}>) {
+  return (
+    <html lang="en">
+      <body className={`antialiased bg-gray-50 text-black`}>
+        {header}
+        {children}
+      </body>
+    </html>
+  )
+}
diff --git a/test/e2e/app-dir/metadata-navigation/app/page.tsx b/test/e2e/app-dir/metadata-navigation/app/page.tsx
@@ -0,0 +1,7 @@
+export default function Home() {
+  return (
+    <div>
+      <h3 id="home-title">Home page content</h3>
+    </div>
+  )
+}
diff --git a/test/e2e/app-dir/metadata-navigation/metadata-navigation.test.ts b/test/e2e/app-dir/metadata-navigation/metadata-navigation.test.ts
@@ -0,0 +1,30 @@
+import { createNextDescribe } from 'e2e-utils'
+
+createNextDescribe(
+  'app-dir - metadata-navigation',
+  {
+    files: __dirname,
+  },
+  ({ next }) => {
+    it('should show the index title', async () => {
+      const browser = await next.browser('/')
+      expect(await browser.elementByCss('title').text()).toBe('Home Layout')
+    })
+
+    it('should show target page metadata after navigation', async () => {
+      const browser = await next.browser('/')
+      await browser.elementByCss('#product-link').click()
+      await browser.waitForElementByCss('#product-title')
+      expect(await browser.elementByCss('title').text()).toBe('Product Layout')
+    })
+
+    it('should show target page metadata after navigation with back', async () => {
+      const browser = await next.browser('/')
+      await browser.elementByCss('#product-link').click()
+      await browser.waitForElementByCss('#product-title')
+      await browser.elementByCss('#home-link').click()
+      await browser.waitForElementByCss('#home-title')
+      expect(await browser.elementByCss('title').text()).toBe('Home Layout')
+    })
+  }
+)