feat(schema,nuxt): add shared/ folder and #shared alias (#28682)

packages/nuxt/src/core/nitro.ts

@@ -17,7 +17,7 @@ import { version as nuxtVersion } from '../../package.json'
 import { distDir } from '../dirs'
 import { toArray } from '../utils'
 import { template as defaultSpaLoadingTemplate } from '../../../ui-templates/dist/templates/spa-loading-icon'
-import { nuxtImportProtections } from './plugins/import-protection'
+import { createImportProtectionPatterns } from './plugins/import-protection'
 import { EXTENSION_RE } from './utils'
 
 const logLevelMapReverse = {
@@ -49,6 +49,8 @@ export async function initNitro (nuxt: Nuxt & { _nitro?: Nitro }) {
       .map(m => m.entryPath!),
   )
 
+  const isNuxtV4 = nuxt.options.future?.compatibilityVersion === 4
+
   const nitroConfig: NitroConfig = defu(nuxt.options.nitro, {
     debug: nuxt.options.debug,
     rootDir: nuxt.options.rootDir,
@@ -66,6 +68,12 @@ export async function initNitro (nuxt: Nuxt & { _nitro?: Nitro }) {
     },
     imports: {
       autoImport: nuxt.options.imports.autoImport as boolean,
+      dirs: isNuxtV4
+        ? [
+            resolve(nuxt.options.rootDir, 'shared', 'utils'),
+            resolve(nuxt.options.rootDir, 'shared', 'types'),
+          ]
+        : [],
       imports: [
         {
           as: '__buildAssetsURL',
@@ -362,11 +370,20 @@ export async function initNitro (nuxt: Nuxt & { _nitro?: Nitro }) {
   // Register nuxt protection patterns
   nitroConfig.rollupConfig!.plugins = await nitroConfig.rollupConfig!.plugins || []
   nitroConfig.rollupConfig!.plugins = toArray(nitroConfig.rollupConfig!.plugins)
+
+  const sharedDir = withTrailingSlash(resolve(nuxt.options.rootDir, nuxt.options.dir.shared))
+  const relativeSharedDir = withTrailingSlash(relative(nuxt.options.rootDir, resolve(nuxt.options.rootDir, nuxt.options.dir.shared)))
+  const sharedPatterns = [/^#shared\//, new RegExp('^' + escapeRE(sharedDir)), new RegExp('^' + escapeRE(relativeSharedDir))]
   nitroConfig.rollupConfig!.plugins!.push(
     ImpoundPlugin.rollup({
       cwd: nuxt.options.rootDir,
-      patterns: nuxtImportProtections(nuxt, { isNitro: true }),
-      exclude: [/core[\\/]runtime[\\/]nitro[\\/]renderer/],
+      include: sharedPatterns,
+      patterns: createImportProtectionPatterns(nuxt, { context: 'shared' }),
+    }),
+    ImpoundPlugin.rollup({
+      cwd: nuxt.options.rootDir,
+      patterns: createImportProtectionPatterns(nuxt, { context: 'nitro-app' }),
+      exclude: [/core[\\/]runtime[\\/]nitro[\\/]renderer/, ...sharedPatterns],
     }),
   )
 

packages/nuxt/src/core/nuxt.ts

@@ -18,7 +18,6 @@ import type { DateString } from 'compatx'
 import escapeRE from 'escape-string-regexp'
 import { withTrailingSlash, withoutLeadingSlash } from 'ufo'
 import { ImpoundPlugin } from 'impound'
-import type { ImpoundOptions } from 'impound'
 import defu from 'defu'
 import { gt, satisfies } from 'semver'
 import { hasTTY, isCI } from 'std-env'
@@ -32,7 +31,7 @@ import { distDir, pkgDir } from '../dirs'
 import { version } from '../../package.json'
 import { scriptsStubsPreset } from '../imports/presets'
 import { resolveTypePath } from './utils/types'
-import { nuxtImportProtections } from './plugins/import-protection'
+import { createImportProtectionPatterns } from './plugins/import-protection'
 import { UnctxTransformPlugin } from './plugins/unctx'
 import { TreeShakeComposablesPlugin } from './plugins/tree-shake'
 import { DevOnlyPlugin } from './plugins/dev-only'
@@ -249,16 +248,28 @@ async function initNuxt (nuxt: Nuxt) {
   // Add plugin normalization plugin
   addBuildPlugin(RemovePluginMetadataPlugin(nuxt))
 
+  // shared folder import protection
+  const sharedDir = withTrailingSlash(resolve(nuxt.options.rootDir, nuxt.options.dir.shared))
+  const relativeSharedDir = withTrailingSlash(relative(nuxt.options.rootDir, resolve(nuxt.options.rootDir, nuxt.options.dir.shared)))
+  const sharedPatterns = [/^#shared\//, new RegExp('^' + escapeRE(sharedDir)), new RegExp('^' + escapeRE(relativeSharedDir))]
+  const sharedProtectionConfig = {
+    cwd: nuxt.options.rootDir,
+    include: sharedPatterns,
+    patterns: createImportProtectionPatterns(nuxt, { context: 'shared' }),
+  }
+  addVitePlugin(() => ImpoundPlugin.vite(sharedProtectionConfig), { server: false })
+  addWebpackPlugin(() => ImpoundPlugin.webpack(sharedProtectionConfig), { server: false })
+
   // Add import protection
-  const config: ImpoundOptions = {
+  const nuxtProtectionConfig = {
     cwd: nuxt.options.rootDir,
     // Exclude top-level resolutions by plugins
-    exclude: [join(nuxt.options.srcDir, 'index.html')],
-    patterns: nuxtImportProtections(nuxt),
+    exclude: [relative(nuxt.options.rootDir, join(nuxt.options.srcDir, 'index.html')), ...sharedPatterns],
+    patterns: createImportProtectionPatterns(nuxt, { context: 'nuxt-app' }),
   }
-  addVitePlugin(() => Object.assign(ImpoundPlugin.vite({ ...config, error: false }), { name: 'nuxt:import-protection' }), { client: false })
-  addVitePlugin(() => Object.assign(ImpoundPlugin.vite({ ...config, error: true }), { name: 'nuxt:import-protection' }), { server: false })
-  addWebpackPlugin(() => ImpoundPlugin.webpack(config))
+  addVitePlugin(() => Object.assign(ImpoundPlugin.vite({ ...nuxtProtectionConfig, error: false }), { name: 'nuxt:import-protection' }), { client: false })
+  addVitePlugin(() => Object.assign(ImpoundPlugin.vite({ ...nuxtProtectionConfig, error: true }), { name: 'nuxt:import-protection' }), { server: false })
+  addWebpackPlugin(() => ImpoundPlugin.webpack(nuxtProtectionConfig))
 
   // add resolver for modules used in virtual files
   addVitePlugin(() => resolveDeepImportsPlugin(nuxt), { client: false })

packages/nuxt/src/core/plugins/import-protection.ts

@@ -9,12 +9,17 @@ interface ImportProtectionOptions {
   exclude?: Array<RegExp | string>
 }
 
-export const nuxtImportProtections = (nuxt: { options: NuxtOptions }, options: { isNitro?: boolean } = {}) => {
+interface NuxtImportProtectionOptions {
+  context: 'nuxt-app' | 'nitro-app' | 'shared'
+}
+
+export const createImportProtectionPatterns = (nuxt: { options: NuxtOptions }, options: NuxtImportProtectionOptions) => {
   const patterns: ImportProtectionOptions['patterns'] = []
+  const context = contextFlags[options.context]
 
   patterns.push([
     /^(nuxt|nuxt3|nuxt-nightly)$/,
-    '`nuxt`, `nuxt3` or `nuxt-nightly` cannot be imported directly.' + (options.isNitro ? '' : ' Instead, import runtime Nuxt composables from `#app` or `#imports`.'),
+    `\`nuxt\`, or \`nuxt-nightly\` cannot be imported directly in ${context}.` + (options.context === 'nuxt-app' ? ' Instead, import runtime Nuxt composables from `#app` or `#imports`.' : ''),
   ])
 
   patterns.push([
@@ -26,27 +31,33 @@ export const nuxtImportProtections = (nuxt: { options: NuxtOptions }, options: {
 
   for (const mod of nuxt.options.modules.filter(m => typeof m === 'string')) {
     patterns.push([
-      new RegExp(`^${escapeRE(mod as string)}$`),
+      new RegExp(`^${escapeRE(mod)}$`),
       'Importing directly from module entry-points is not allowed.',
     ])
   }
 
   for (const i of [/(^|node_modules\/)@nuxt\/(kit|test-utils)/, /(^|node_modules\/)nuxi/, /(^|node_modules\/)nitro(?:pack)?(?:-nightly)?(?:$|\/)(?!(?:dist\/)?runtime|types)/, /(^|node_modules\/)nuxt\/(config|kit|schema)/]) {
-    patterns.push([i, 'This module cannot be imported' + (options.isNitro ? ' in server runtime.' : ' in the Vue part of your app.')])
+    patterns.push([i, `This module cannot be imported in ${context}.`])
   }
 
-  if (options.isNitro) {
+  if (options.context === 'nitro-app' || options.context === 'shared') {
     for (const i of ['#app', /^#build(\/|$)/]) {
-      patterns.push([i, 'Vue app aliases are not allowed in server runtime.'])
+      patterns.push([i, `Vue app aliases are not allowed in ${context}.`])
     }
   }
 
-  if (!options.isNitro) {
+  if (options.context === 'nuxt-app' || options.context === 'shared') {
     patterns.push([
       new RegExp(escapeRE(relative(nuxt.options.srcDir, resolve(nuxt.options.srcDir, nuxt.options.serverDir || 'server'))) + '\\/(api|routes|middleware|plugins)\\/'),
-      'Importing from server is not allowed in the Vue part of your app.',
+      `Importing from server is not allowed in ${context}.`,
     ])
   }
 
   return patterns
 }
+
+const contextFlags = {
+  'nitro-app': 'server runtime',
+  'nuxt-app': 'the Vue part of your app',
+  'shared': 'the #shared directory',
+} as const

packages/nuxt/src/imports/module.ts

@@ -54,6 +54,8 @@ export default defineNuxtModule<Partial<ImportsOptions>>({
 
     await nuxt.callHook('imports:context', ctx)
 
+    const isNuxtV4 = nuxt.options.future?.compatibilityVersion === 4
+
     // composables/ dirs from all layers
     let composablesDirs: string[] = []
     if (options.scan) {
@@ -64,6 +66,12 @@ export default defineNuxtModule<Partial<ImportsOptions>>({
         }
         composablesDirs.push(resolve(layer.config.srcDir, 'composables'))
         composablesDirs.push(resolve(layer.config.srcDir, 'utils'))
+
+        if (isNuxtV4) {
+          composablesDirs.push(resolve(layer.config.rootDir, 'shared', 'utils'))
+          composablesDirs.push(resolve(layer.config.rootDir, 'shared', 'types'))
+        }
+
         for (const dir of (layer.config.imports?.dirs ?? [])) {
           if (!dir) {
             continue

packages/nuxt/test/import-protection.test.ts

@@ -1,7 +1,7 @@
 import { normalize } from 'pathe'
 import { describe, expect, it } from 'vitest'
 import { ImpoundPlugin } from 'impound'
-import { nuxtImportProtections } from '../src/core/plugins/import-protection'
+import { createImportProtectionPatterns } from '../src/core/plugins/import-protection'
 import type { NuxtOptions } from '../schema'
 
 const testsToTriggerOn = [
@@ -28,7 +28,7 @@ const testsToTriggerOn = [
 
 describe('import protection', () => {
   it.each(testsToTriggerOn)('should protect %s', async (id, importer, isProtected) => {
-    const result = await transformWithImportProtection(id, importer)
+    const result = await transformWithImportProtection(id, importer, 'nuxt-app')
     if (!isProtected) {
       expect(result).toBeNull()
     } else {
@@ -38,16 +38,16 @@ describe('import protection', () => {
   })
 })
 
-const transformWithImportProtection = (id: string, importer: string) => {
+const transformWithImportProtection = (id: string, importer: string, context: 'nitro-app' | 'nuxt-app' | 'shared') => {
   const plugin = ImpoundPlugin.rollup({
     cwd: '/root',
-    patterns: nuxtImportProtections({
+    patterns: createImportProtectionPatterns({
       options: {
         modules: ['some-nuxt-module'],
         srcDir: '/root/src/',
         serverDir: '/root/src/server',
       } satisfies Partial<NuxtOptions> as NuxtOptions,
-    }),
+    }, { context }),
   })
 
   return (plugin as any).resolveId.call({ error: () => {} }, id, importer)

packages/schema/src/config/common.ts

@@ -355,6 +355,11 @@ export default defineUntypedSchema({
      */
     plugins: 'plugins',
 
+    /**
+     * The shared directory. This directory is shared between the app and the server.
+     */
+    shared: 'shared',
+
     /**
      * The directory containing your static files, which will be directly accessible via the Nuxt server
      * and copied across into your `dist` folder when your app is generated.
@@ -424,12 +429,13 @@ export default defineUntypedSchema({
    */
   alias: {
     $resolve: async (val: Record<string, string>, get): Promise<Record<string, string>> => {
-      const [srcDir, rootDir, assetsDir, publicDir, buildDir] = await Promise.all([get('srcDir'), get('rootDir'), get('dir.assets'), get('dir.public'), get('buildDir')]) as [string, string, string, string, string]
+      const [srcDir, rootDir, assetsDir, publicDir, buildDir, sharedDir] = await Promise.all([get('srcDir'), get('rootDir'), get('dir.assets'), get('dir.public'), get('buildDir'), get('dir.shared')]) as [string, string, string, string, string, string]
       return {
         '~': srcDir,
         '@': srcDir,
         '~~': rootDir,
         '@@': rootDir,
+        '#shared': resolve(rootDir, sharedDir),
         [basename(assetsDir)]: resolve(srcDir, assetsDir),
         [basename(publicDir)]: resolve(srcDir, publicDir),
         '#build': buildDir,

packages/vite/src/server.ts

@@ -7,6 +7,7 @@ import { joinURL, withTrailingSlash, withoutLeadingSlash } from 'ufo'
 import type { ViteConfig } from '@nuxt/schema'
 import defu from 'defu'
 import type { Nitro } from 'nitro/types'
+import escapeStringRegexp from 'escape-string-regexp'
 import type { ViteBuildContext } from './vite'
 import { createViteLogger } from './utils/logger'
 import { initViteNodeServer } from './vite-node'
@@ -80,7 +81,13 @@ export async function buildServer (ctx: ViteBuildContext) {
       ssr: true,
       rollupOptions: {
         input: { server: entry },
-        external: ['nitro/runtime', '#internal/nuxt/paths', '#internal/nuxt/app-config'],
+        external: [
+          'nitro/runtime',
+          '#internal/nuxt/paths',
+          '#internal/nuxt/app-config',
+          '#shared',
+          new RegExp('^' + escapeStringRegexp(withTrailingSlash(resolve(ctx.nuxt.options.rootDir, ctx.nuxt.options.dir.shared)))),
+        ],
         output: {
           entryFileNames: '[name].mjs',
           format: 'module',

packages/vite/src/utils/external.ts

@@ -1,9 +1,13 @@
 import type { ExternalsOptions } from 'externality'
 import { ExternalsDefaults, isExternal } from 'externality'
 import type { ViteDevServer } from 'vite'
+import escapeStringRegexp from 'escape-string-regexp'
+import { withTrailingSlash } from 'ufo'
+import type { Nuxt } from 'nuxt/schema'
+import { resolve } from 'pathe'
 import { toArray } from '.'
 
-export function createIsExternal (viteServer: ViteDevServer, rootDir: string, modulesDirs?: string[]) {
+export function createIsExternal (viteServer: ViteDevServer, nuxt: Nuxt) {
   const externalOpts: ExternalsOptions = {
     inline: [
       /virtual:/,
@@ -16,15 +20,17 @@ export function createIsExternal (viteServer: ViteDevServer, rootDir: string, mo
       ),
     ],
     external: [
+      '#shared',
+      new RegExp('^' + escapeStringRegexp(withTrailingSlash(resolve(nuxt.options.rootDir, nuxt.options.dir.shared)))),
       ...(viteServer.config.ssr.external as string[]) || [],
       /node_modules/,
     ],
     resolve: {
-      modules: modulesDirs,
+      modules: nuxt.options.modulesDir,
       type: 'module',
       extensions: ['.ts', '.js', '.json', '.vue', '.mjs', '.jsx', '.tsx', '.wasm'],
     },
   }
 
-  return (id: string) => isExternal(id, rootDir, externalOpts)
+  return (id: string) => isExternal(id, nuxt.options.rootDir, externalOpts)
 }

packages/vite/src/vite-node.ts

@@ -140,7 +140,7 @@ function createViteNodeApp (ctx: ViteBuildContext, invalidates: Set<string> = ne
       },
     })
 
-    const isExternal = createIsExternal(viteServer, ctx.nuxt.options.rootDir, ctx.nuxt.options.modulesDir)
+    const isExternal = createIsExternal(viteServer, ctx.nuxt)
     node.shouldExternalize = async (id: string) => {
       const result = await isExternal(id)
       if (result?.external) {

packages/webpack/src/configs/server.ts

@@ -1,4 +1,4 @@
-import { isAbsolute } from 'pathe'
+import { isAbsolute, resolve } from 'pathe'
 import ForkTSCheckerWebpackPlugin from 'fork-ts-checker-webpack-plugin'
 import { logger } from '@nuxt/kit'
 import type { WebpackConfigContext } from '../utils/config'
@@ -53,7 +53,11 @@ function serverStandalone (ctx: WebpackConfigContext) {
     '#',
     ...ctx.options.build.transpile,
   ]
-  const external = ['nitro/runtime']
+  const external = [
+    'nitro/runtime',
+    '#shared',
+    resolve(ctx.nuxt.options.rootDir, ctx.nuxt.options.dir.shared),
+  ]
   if (!ctx.nuxt.options.dev) {
     external.push('#internal/nuxt/paths', '#internal/nuxt/app-config')
   }