Bypass empty pages folder for layouts

packages/next/build/entries.ts

@@ -69,12 +69,14 @@ export function createPagesMapping({
   pageExtensions,
   pagePaths,
   pagesType,
+  pagesDir,
 }: {
   hasServerComponents: boolean
   isDev: boolean
   pageExtensions: string[]
   pagePaths: string[]
   pagesType: 'pages' | 'root' | 'app'
+  pagesDir: string | undefined
 }): { [page: string]: string } {
   const previousPages: { [key: string]: string } = {}
   const pages = pagePaths.reduce<{ [key: string]: string }>(
@@ -133,7 +135,7 @@ export function createPagesMapping({
   // In development we always alias these to allow Webpack to fallback to
   // the correct source file so that HMR can work properly when a file is
   // added or removed.
-  const root = isDev ? PAGES_DIR_ALIAS : 'next/dist/pages'
+  const root = isDev && pagesDir ? PAGES_DIR_ALIAS : 'next/dist/pages'
 
   return {
     '/_app': `${root}/_app`,
@@ -149,7 +151,7 @@ interface CreateEntrypointsParams {
   envFiles: LoadedEnvFiles
   isDev?: boolean
   pages: { [page: string]: string }
-  pagesDir: string
+  pagesDir?: string
   previewMode: __ApiPreviewProps
   rootDir: string
   rootPaths?: Record<string, string>
@@ -366,7 +368,7 @@ export async function createEntrypoints(params: CreateEntrypointsParams) {
 
       // Handle paths that have aliases
       const pageFilePath = (() => {
-        if (absolutePagePath.startsWith(PAGES_DIR_ALIAS)) {
+        if (absolutePagePath.startsWith(PAGES_DIR_ALIAS) && pagesDir) {
           return absolutePagePath.replace(PAGES_DIR_ALIAS, pagesDir)
         }
 
@@ -444,12 +446,7 @@ export async function createEntrypoints(params: CreateEntrypointsParams) {
               })
             }
           } else {
-            server[serverBundlePath] = isServerComponent
-              ? {
-                  import: mappings[page],
-                  layer: WEBPACK_LAYERS.server,
-                }
-              : [mappings[page]]
+            server[serverBundlePath] = [mappings[page]]
           }
         },
         onEdgeServer: () => {
@@ -490,7 +487,7 @@ export async function createEntrypoints(params: CreateEntrypointsParams) {
   await Promise.all(Object.keys(pages).map(getEntryHandler(pages, 'pages')))
 
   if (nestedMiddleware.length > 0) {
-    throw new NestedMiddlewareError(nestedMiddleware, rootDir, pagesDir)
+    throw new NestedMiddlewareError(nestedMiddleware, rootDir, pagesDir!)
   }
 
   return {

packages/next/build/index.ts

@@ -314,7 +314,9 @@ export default async function build(
         eventCliSession(dir, config, {
           webpackVersion: 5,
           cliCommand: 'build',
-          isSrcDir: path.relative(dir, pagesDir!).startsWith('src'),
+          isSrcDir:
+            (!!pagesDir && path.relative(dir, pagesDir).startsWith('src')) ||
+            (!!appDir && path.relative(dir, appDir).startsWith('src')),
           hasNowJson: !!(await findUp('now.json', { cwd: dir })),
           isCustomServer: null,
         })
@@ -395,7 +397,8 @@ export default async function build(
                   config.eslint?.dirs,
                   config.experimental.cpus,
                   config.experimental.workerThreads,
-                  telemetry
+                  telemetry,
+                  !!config.experimental.appDir
                 )
               }),
         ])
@@ -436,14 +439,16 @@ export default async function build(
 
       const isLikeServerless = isTargetLikeServerless(target)
 
-      const pagesPaths = await nextBuildSpan
-        .traceChild('collect-pages')
-        .traceAsyncFn(() =>
-          recursiveReadDir(
-            pagesDir,
-            new RegExp(`\\.(?:${config.pageExtensions.join('|')})$`)
-          )
-        )
+      const pagesPaths = pagesDir
+        ? await nextBuildSpan
+            .traceChild('collect-pages')
+            .traceAsyncFn(() =>
+              recursiveReadDir(
+                pagesDir,
+                new RegExp(`\\.(?:${config.pageExtensions.join('|')})$`)
+              )
+            )
+        : []
 
       let appPaths: string[] | undefined
 
@@ -462,9 +467,11 @@ export default async function build(
         `^${MIDDLEWARE_FILENAME}\\.(?:${config.pageExtensions.join('|')})$`
       )
 
-      const rootPaths = (
-        await flatReaddir(join(pagesDir, '..'), middlewareDetectionRegExp)
-      ).map((absoluteFile) => absoluteFile.replace(dir, ''))
+      const rootPaths = pagesDir
+        ? (
+            await flatReaddir(join(pagesDir, '..'), middlewareDetectionRegExp)
+          ).map((absoluteFile) => absoluteFile.replace(dir, ''))
+        : []
 
       // needed for static exporting since we want to replace with HTML
       // files
@@ -487,6 +494,7 @@ export default async function build(
             pageExtensions: config.pageExtensions,
             pagesType: 'pages',
             pagePaths: pagesPaths,
+            pagesDir,
           })
         )
 
@@ -502,6 +510,7 @@ export default async function build(
               isDev: false,
               pagesType: 'app',
               pageExtensions: config.pageExtensions,
+              pagesDir: pagesDir,
             })
           )
       }
@@ -514,6 +523,7 @@ export default async function build(
           pageExtensions: config.pageExtensions,
           pagePaths: rootPaths,
           pagesType: 'root',
+          pagesDir: pagesDir,
         })
       }
 
@@ -1256,7 +1266,7 @@ export default async function build(
                     : appPaths?.find((p) => p.startsWith(actualPage + '/page.'))
 
                 const pageRuntime =
-                  pageType === 'pages' && pagePath
+                  pagesDir && pageType === 'pages' && pagePath
                     ? (
                         await getPageStaticInfo({
                           pageFilePath: join(pagesDir, pagePath),
@@ -1913,6 +1923,7 @@ export default async function build(
                   await staticWorkers.end()
                 }
               : undefined,
+            appPaths,
           }
           const exportConfig: any = {
             ...config,

packages/next/build/utils.ts

@@ -305,7 +305,7 @@ export async function printTreeView(
   }: {
     distPath: string
     buildId: string
-    pagesDir: string
+    pagesDir?: string
     pageExtensions: string[]
     buildManifest: BuildManifest
     appBuildManifest?: AppBuildManifest
@@ -345,7 +345,8 @@ export async function printTreeView(
       .replace(/(?:^|[.-])([0-9a-z]{6})[0-9a-z]{14}(?=\.)/, '.$1')
 
   // Check if we have a custom app.
-  const hasCustomApp = await findPageFile(pagesDir, '/_app', pageExtensions)
+  const hasCustomApp =
+    pagesDir && (await findPageFile(pagesDir, '/_app', pageExtensions, false))
 
   const filterAndSortList = (list: ReadonlyArray<string>) =>
     list
@@ -1081,7 +1082,13 @@ export async function isPageStatic({
           getStaticProps: mod.getStaticProps,
         }
       } else {
-        componentsResult = await loadComponents(distDir, page, serverless)
+        componentsResult = await loadComponents(
+          distDir,
+          page,
+          serverless,
+          false,
+          false
+        )
       }
       const Comp = componentsResult.Component
 
@@ -1207,7 +1214,13 @@ export async function hasCustomGetInitialProps(
 ): Promise<boolean> {
   require('../shared/lib/runtime-config').setConfig(runtimeEnvConfig)
 
-  const components = await loadComponents(distDir, page, isLikeServerless)
+  const components = await loadComponents(
+    distDir,
+    page,
+    isLikeServerless,
+    false,
+    false
+  )
   let mod = components.ComponentMod
 
   if (checkingApp) {
@@ -1226,7 +1239,13 @@ export async function getNamedExports(
   runtimeEnvConfig: any
 ): Promise<Array<string>> {
   require('../shared/lib/runtime-config').setConfig(runtimeEnvConfig)
-  const components = await loadComponents(distDir, page, isLikeServerless)
+  const components = await loadComponents(
+    distDir,
+    page,
+    isLikeServerless,
+    false,
+    false
+  )
   let mod = components.ComponentMod
 
   return Object.keys(mod)

packages/next/build/webpack-config.ts

@@ -518,7 +518,7 @@ export default async function getBaseWebpackConfig(
     entrypoints: webpack.EntryObject
     hasReactRoot: boolean
     isDevFallback?: boolean
-    pagesDir: string
+    pagesDir?: string
     reactProductionProfiling?: boolean
     rewrites: CustomRoutes['rewrites']
     runWebpackSpan: Span
@@ -794,24 +794,30 @@ export default async function getBaseWebpackConfig(
 
   if (dev) {
     customAppAliases[`${PAGES_DIR_ALIAS}/_app`] = [
-      ...rawPageExtensions.reduce((prev, ext) => {
-        prev.push(path.join(pagesDir, `_app.${ext}`))
-        return prev
-      }, [] as string[]),
+      ...(pagesDir
+        ? rawPageExtensions.reduce((prev, ext) => {
+            prev.push(path.join(pagesDir, `_app.${ext}`))
+            return prev
+          }, [] as string[])
+        : []),
       'next/dist/pages/_app.js',
     ]
     customAppAliases[`${PAGES_DIR_ALIAS}/_error`] = [
-      ...rawPageExtensions.reduce((prev, ext) => {
-        prev.push(path.join(pagesDir, `_error.${ext}`))
-        return prev
-      }, [] as string[]),
+      ...(pagesDir
+        ? rawPageExtensions.reduce((prev, ext) => {
+            prev.push(path.join(pagesDir, `_error.${ext}`))
+            return prev
+          }, [] as string[])
+        : []),
       'next/dist/pages/_error.js',
     ]
     customDocumentAliases[`${PAGES_DIR_ALIAS}/_document`] = [
-      ...rawPageExtensions.reduce((prev, ext) => {
-        prev.push(path.join(pagesDir, `_document.${ext}`))
-        return prev
-      }, [] as string[]),
+      ...(pagesDir
+        ? rawPageExtensions.reduce((prev, ext) => {
+            prev.push(path.join(pagesDir, `_document.${ext}`))
+            return prev
+          }, [] as string[])
+        : []),
       `next/dist/pages/_document.js`,
     ]
   }
@@ -850,7 +856,7 @@ export default async function getBaseWebpackConfig(
       ...customDocumentAliases,
       ...customRootAliases,
 
-      [PAGES_DIR_ALIAS]: pagesDir,
+      ...(pagesDir ? { [PAGES_DIR_ALIAS]: pagesDir } : {}),
       ...(appDir
         ? {
             [APP_DIR_ALIAS]: appDir,
@@ -2051,7 +2057,9 @@ export default async function getBaseWebpackConfig(
   webpackConfig = await buildConfiguration(webpackConfig, {
     supportedBrowsers,
     rootDirectory: dir,
-    customAppFile: new RegExp(escapeStringRegexp(path.join(pagesDir, `_app`))),
+    customAppFile: pagesDir
+      ? new RegExp(escapeStringRegexp(path.join(pagesDir, `_app`)))
+      : undefined,
     isDevelopment: dev,
     isServer: isNodeServer || isEdgeServer,
     isEdgeRuntime: isEdgeServer,

packages/next/build/webpack/config/index.ts

@@ -25,7 +25,7 @@ export async function build(
   }: {
     supportedBrowsers: string[] | undefined
     rootDirectory: string
-    customAppFile: RegExp
+    customAppFile: RegExp | undefined
     isDevelopment: boolean
     isServer: boolean
     isEdgeRuntime: boolean

packages/next/build/webpack/config/utils.ts

@@ -4,7 +4,7 @@ import type { NextConfigComplete } from '../../../server/config-shared'
 export type ConfigurationContext = {
   supportedBrowsers: string[] | undefined
   rootDirectory: string
-  customAppFile: RegExp
+  customAppFile: RegExp | undefined
 
   isDevelopment: boolean
   isProduction: boolean

packages/next/build/webpack/plugins/react-loadable-plugin.ts

@@ -53,9 +53,14 @@ function getChunkGroupFromBlock(
 function buildManifest(
   _compiler: webpack.Compiler,
   compilation: webpack.Compilation,
-  pagesDir: string,
+  pagesDir: string | undefined,
   dev: boolean
 ) {
+  // If there's no pagesDir, output an empty manifest
+  if (!pagesDir) {
+    return {}
+  }
+
   let manifest: { [k: string]: { id: string | number; files: string[] } } = {}
 
   // This is allowed:
@@ -145,13 +150,13 @@ function buildManifest(
 
 export class ReactLoadablePlugin {
   private filename: string
-  private pagesDir: string
+  private pagesDir?: string
   private runtimeAsset?: string
   private dev: boolean
 
   constructor(opts: {
     filename: string
-    pagesDir: string
+    pagesDir?: string
     runtimeAsset?: string
     dev: boolean
   }) {