Improve experimental feature naming (vercel#41060)

Rename `optoutServerComponentsBundle` to `serverComponentsExternalPackages` which describes the feature better.

## Bug

- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have a helpful link attached, see `contributing.md`

## Feature

- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have a helpful link attached, see `contributing.md`

## Documentation / Examples

- [ ] Make sure the linting passes by running `pnpm lint`
- [ ] The "examples guidelines" are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing/examples/adding-examples.md)

packages/next/build/webpack-config.ts

@@ -124,6 +124,12 @@ function errorIfEnvConflicted(config: NextConfigComplete, key: string) {
   }
 }
 
+function isResourceInPackages(resource: string, packageNames?: string[]) {
+  return packageNames?.some((p: string) =>
+    new RegExp('[/\\\\]node_modules[/\\\\]' + p + '[/\\\\]').test(resource)
+  )
+}
+
 export function getDefineEnv({
   dev,
   config,
@@ -1137,8 +1143,9 @@ export default async function getBaseWebpackConfig(
       if (layer === WEBPACK_LAYERS.server) {
         // All packages should be bundled for the server layer if they're not opted out.
         if (
-          config.experimental.optoutServerComponentsBundle?.some((p: string) =>
-            new RegExp('node_modules[/\\\\]' + p + '[/\\\\]').test(res)
+          isResourceInPackages(
+            res,
+            config.experimental.serverComponentsExternalPackages
           )
         ) {
           return `${externalType} ${request}`
@@ -1514,16 +1521,18 @@ export default async function getBaseWebpackConfig(
               {
                 issuerLayer: WEBPACK_LAYERS.server,
                 test: (req: string) => {
+                  // If it's not a source code file, or has been opted out of
+                  // bundling, don't resolve it.
                   if (
                     !codeCondition.test.test(req) ||
-                    config.experimental.optoutServerComponentsBundle?.some(
-                      (mod) => {
-                        return req.includes('/node_modules/' + mod + '/')
-                      }
+                    isResourceInPackages(
+                      req,
+                      config.experimental.serverComponentsExternalPackages
                     )
                   ) {
                     return false
                   }
+
                   return true
                 },
                 resolve: process.env.__NEXT_REACT_CHANNEL

packages/next/server/config-schema.ts

@@ -323,7 +323,7 @@ const configSchema = {
         optimisticClientCache: {
           type: 'boolean',
         },
-        optoutServerComponentsBundle: {
+        serverComponentsExternalPackages: {
           items: {
             type: 'string',
           },

packages/next/server/config-shared.ts

@@ -154,7 +154,7 @@ export interface ExperimentalConfig {
   adjustFontFallbacksWithSizeAdjust?: boolean
 
   // A list of packages that should be treated as external in the RSC server build
-  optoutServerComponentsBundle?: string[]
+  serverComponentsExternalPackages?: string[]
 
   fontLoaders?: { [fontLoader: string]: any }
 }

test/e2e/app-dir/rsc-basic/next.config.js

@@ -5,7 +5,7 @@ module.exports = {
   },
   experimental: {
     appDir: true,
-    optoutServerComponentsBundle: ['conditional-exports-optout'],
+    serverComponentsExternalPackages: ['conditional-exports-optout'],
   },
   rewrites: async () => {
     return {