Bundle the installed react for middleware (#65811)

### What

Let `middleware` and `instrumentation` apply `react-server` exports
condition names first. When bundle the react and react-dom, bundle the
installed version instead of the built-in version.

Renamed "app" group for webpack layers to "bundled", which indicates it
will bundle all the dependencies.

### Why

Middleware and instrument are sort of isolated from app router and pages
router, if they're using react should pick up from the installed
version. Since they're in server layer so they only need to bundle the
`react-server` conditions.

x-ref: [slack
thread](https://vercel.slack.com/archives/C046HAU4H7F/p1715790385748169)

packages/next/src/build/handle-externals.ts

@@ -10,7 +10,7 @@ import {
   NODE_ESM_RESOLVE_OPTIONS,
   NODE_RESOLVE_OPTIONS,
 } from './webpack-config'
-import { isWebpackAppLayer, isWebpackServerOnlyLayer } from './utils'
+import { isWebpackBundledLayer, isWebpackServerOnlyLayer } from './utils'
 import { normalizePathSep } from '../shared/lib/page-path/normalize-path-sep'
 const reactPackagesRegex = /^(react|react-dom|react-server-dom-webpack)($|\/)/
 
@@ -174,7 +174,7 @@ export function makeExternalHandler({
       return `commonjs next/dist/lib/import-next-warning`
     }
 
-    const isAppLayer = isWebpackAppLayer(layer)
+    const isAppLayer = isWebpackBundledLayer(layer)
 
     // Relative requires don't need custom resolution, because they
     // are relative to requests we've already resolved here.

packages/next/src/build/utils.ts

@@ -2238,6 +2238,15 @@ export function getSupportedBrowsers(
   return MODERN_BROWSERSLIST_TARGET
 }
 
+// Use next/dist/compiled/react packages instead of installed react
+export function isWebpackBuiltinReactLayer(
+  layer: WebpackLayerName | null | undefined
+): boolean {
+  return Boolean(
+    layer && WEBPACK_LAYERS.GROUP.builtinReact.includes(layer as any)
+  )
+}
+
 export function isWebpackServerOnlyLayer(
   layer: WebpackLayerName | null | undefined
 ): boolean {
@@ -2260,8 +2269,8 @@ export function isWebpackDefaultLayer(
   return layer === null || layer === undefined
 }
 
-export function isWebpackAppLayer(
+export function isWebpackBundledLayer(
   layer: WebpackLayerName | null | undefined
 ): boolean {
-  return Boolean(layer && WEBPACK_LAYERS.GROUP.app.includes(layer as any))
+  return Boolean(layer && WEBPACK_LAYERS.GROUP.bundled.includes(layer as any))
 }

packages/next/src/build/webpack-config.ts

@@ -9,7 +9,8 @@ import { escapeStringRegexp } from '../shared/lib/escape-regexp'
 import { WEBPACK_LAYERS, WEBPACK_RESOURCE_QUERIES } from '../lib/constants'
 import type { WebpackLayerName } from '../lib/constants'
 import {
-  isWebpackAppLayer,
+  isWebpackBuiltinReactLayer,
+  isWebpackBundledLayer,
   isWebpackClientOnlyLayer,
   isWebpackDefaultLayer,
   isWebpackServerOnlyLayer,
@@ -557,13 +558,12 @@ export default async function getBaseWebpackConfig(
   // Loader for API routes needs to be differently configured as it shouldn't
   // have RSC transpiler enabled, so syntax checks such as invalid imports won't
   // be performed.
-  const apiRoutesLayerLoaders =
-    hasAppDir && useSWCLoader
-      ? getSwcLoader({
-          serverComponents: false,
-          bundleLayer: WEBPACK_LAYERS.api,
-        })
-      : defaultLoaders.babel
+  const apiRoutesLayerLoaders = useSWCLoader
+    ? getSwcLoader({
+        serverComponents: false,
+        bundleLayer: WEBPACK_LAYERS.api,
+      })
+    : defaultLoaders.babel
 
   const pageExtensions = config.pageExtensions
 
@@ -1292,7 +1292,7 @@ export default async function getBaseWebpackConfig(
                 test: /next[\\/]dist[\\/](esm[\\/])?server[\\/]future[\\/]route-modules[\\/]app-page[\\/]module/,
               },
               {
-                issuerLayer: isWebpackAppLayer,
+                issuerLayer: isWebpackBundledLayer,
                 resolve: {
                   alias: createNextApiEsmAliases(),
                 },
@@ -1314,7 +1314,7 @@ export default async function getBaseWebpackConfig(
         ...(hasAppDir && !isClient
           ? [
               {
-                issuerLayer: isWebpackServerOnlyLayer,
+                issuerLayer: isWebpackBuiltinReactLayer,
                 test: {
                   // Resolve it if it is a source code file, and it has NOT been
                   // opted out of bundling.
@@ -1376,7 +1376,7 @@ export default async function getBaseWebpackConfig(
                 // Alias react for switching between default set and share subset.
                 oneOf: [
                   {
-                    issuerLayer: isWebpackServerOnlyLayer,
+                    issuerLayer: isWebpackBuiltinReactLayer,
                     test: {
                       // Resolve it if it is a source code file, and it has NOT been
                       // opted out of bundling.
@@ -1457,11 +1457,17 @@ export default async function getBaseWebpackConfig(
               test: codeCondition.test,
               issuerLayer: WEBPACK_LAYERS.middleware,
               use: middlewareLayerLoaders,
+              resolve: {
+                conditionNames: reactServerCondition,
+              },
             },
             {
               test: codeCondition.test,
               issuerLayer: WEBPACK_LAYERS.instrument,
               use: instrumentLayerLoaders,
+              resolve: {
+                conditionNames: reactServerCondition,
+              },
             },
             ...(hasAppDir
               ? [

packages/next/src/lib/constants.ts

@@ -159,6 +159,11 @@ export type WebpackLayerName =
 const WEBPACK_LAYERS = {
   ...WEBPACK_LAYERS_NAMES,
   GROUP: {
+    builtinReact: [
+      WEBPACK_LAYERS_NAMES.reactServerComponents,
+      WEBPACK_LAYERS_NAMES.actionBrowser,
+      WEBPACK_LAYERS_NAMES.appMetadataRoute,
+    ],
     serverOnly: [
       WEBPACK_LAYERS_NAMES.reactServerComponents,
       WEBPACK_LAYERS_NAMES.actionBrowser,
@@ -174,7 +179,7 @@ const WEBPACK_LAYERS = {
       WEBPACK_LAYERS_NAMES.serverSideRendering,
       WEBPACK_LAYERS_NAMES.appPagesBrowser,
     ],
-    app: [
+    bundled: [
       WEBPACK_LAYERS_NAMES.reactServerComponents,
       WEBPACK_LAYERS_NAMES.actionBrowser,
       WEBPACK_LAYERS_NAMES.appMetadataRoute,

test/e2e/module-layer/middleware.js

@@ -7,5 +7,10 @@ export function middleware(request) {
   if (React.useState) {
     throw new Error('React.useState should not be defined in server layer')
   }
+
+  if (request.nextUrl.pathname === '/react-version') {
+    return new Response(React.version)
+  }
+
   return NextResponse.next()
 }

test/e2e/module-layer/module-layer.test.ts

@@ -4,6 +4,10 @@ import { getRedboxSource, hasRedbox, retry } from 'next-test-utils'
 describe('module layer', () => {
   const { next, isNextStart, isNextDev, isTurbopack } = nextTestSetup({
     files: __dirname,
+    dependencies: {
+      react: '19.0.0-rc-915b914b3a-20240515',
+      'react-dom': '19.0.0-rc-915b914b3a-20240515',
+    },
   })
 
   function runTests() {
@@ -30,6 +34,11 @@ describe('module layer', () => {
       })
     }
 
+    it('should render installed react version for middleware', async () => {
+      const text = await next.fetch('/react-version').then((res) => res.text())
+      expect(text).toContain('19.0.0-rc')
+    })
+
     if (isNextStart) {
       it('should log the build info properly', async () => {
         const cliOutput = next.cliOutput