feat(nuxt): allow configuring treeshakeable composables (#19383)

packages/nuxt/src/core/nuxt.ts

@@ -16,7 +16,8 @@ import { distDir, pkgDir } from '../dirs'
 import { version } from '../../package.json'
 import { ImportProtectionPlugin, vueAppPatterns } from './plugins/import-protection'
 import { UnctxTransformPlugin } from './plugins/unctx'
-import { TreeShakePlugin } from './plugins/tree-shake'
+import type { TreeShakeComposablesPluginOptions } from './plugins/tree-shake'
+import { TreeShakeComposablesPlugin } from './plugins/tree-shake'
 import { DevOnlyPlugin } from './plugins/dev-only'
 import { addModuleTranspiles } from './modules'
 import { initNitro } from './nitro'
@@ -79,22 +80,31 @@ async function initNuxt (nuxt: Nuxt) {
   addVitePlugin(ImportProtectionPlugin.vite(config))
   addWebpackPlugin(ImportProtectionPlugin.webpack(config))
 
-  // Add unctx transform
   nuxt.hook('modules:done', () => {
+    // Add unctx transform
     addVitePlugin(UnctxTransformPlugin(nuxt).vite({ sourcemap: nuxt.options.sourcemap.server || nuxt.options.sourcemap.client }))
     addWebpackPlugin(UnctxTransformPlugin(nuxt).webpack({ sourcemap: nuxt.options.sourcemap.server || nuxt.options.sourcemap.client }))
+
+    // Add composable tree-shaking optimisations
+    const serverTreeShakeOptions : TreeShakeComposablesPluginOptions = {
+      sourcemap: nuxt.options.sourcemap.server,
+      composables: nuxt.options.optimization.treeShake.composables.server
+    }
+    if (Object.keys(serverTreeShakeOptions.composables).length) {
+      addVitePlugin(TreeShakeComposablesPlugin.vite(serverTreeShakeOptions), { client: false })
+      addWebpackPlugin(TreeShakeComposablesPlugin.webpack(serverTreeShakeOptions), { client: false })
+    }
+    const clientTreeShakeOptions : TreeShakeComposablesPluginOptions = {
+      sourcemap: nuxt.options.sourcemap.client,
+      composables: nuxt.options.optimization.treeShake.composables.client
+    }
+    if (Object.keys(clientTreeShakeOptions.composables).length) {
+      addVitePlugin(TreeShakeComposablesPlugin.vite(clientTreeShakeOptions), { server: false })
+      addWebpackPlugin(TreeShakeComposablesPlugin.webpack(clientTreeShakeOptions), { server: false })
+    }
   })
 
   if (!nuxt.options.dev) {
-    const removeFromServer = ['onBeforeMount', 'onMounted', 'onBeforeUpdate', 'onRenderTracked', 'onRenderTriggered', 'onActivated', 'onDeactivated', 'onBeforeUnmount']
-    const removeFromClient = ['onServerPrefetch', 'onRenderTracked', 'onRenderTriggered']
-
-    // Add tree-shaking optimisations for SSR - build time only
-    addVitePlugin(TreeShakePlugin.vite({ sourcemap: nuxt.options.sourcemap.server, treeShake: removeFromServer }), { client: false })
-    addVitePlugin(TreeShakePlugin.vite({ sourcemap: nuxt.options.sourcemap.client, treeShake: removeFromClient }), { server: false })
-    addWebpackPlugin(TreeShakePlugin.webpack({ sourcemap: nuxt.options.sourcemap.server, treeShake: removeFromServer }), { client: false })
-    addWebpackPlugin(TreeShakePlugin.webpack({ sourcemap: nuxt.options.sourcemap.client, treeShake: removeFromClient }), { server: false })
-
     // DevOnly component tree-shaking - build time only
     addVitePlugin(DevOnlyPlugin.vite({ sourcemap: nuxt.options.sourcemap.server || nuxt.options.sourcemap.client }))
     addWebpackPlugin(DevOnlyPlugin.webpack({ sourcemap: nuxt.options.sourcemap.server || nuxt.options.sourcemap.client }))

packages/nuxt/src/core/plugins/tree-shake.ts

@@ -4,16 +4,22 @@ import { parseQuery, parseURL } from 'ufo'
 import MagicString from 'magic-string'
 import { createUnplugin } from 'unplugin'
 
-interface TreeShakePluginOptions {
+type ImportPath = string
+
+export interface TreeShakeComposablesPluginOptions {
   sourcemap?: boolean
-  treeShake: string[]
+  composables: Record<ImportPath, string[]>
 }
 
-export const TreeShakePlugin = createUnplugin((options: TreeShakePluginOptions) => {
+export const TreeShakeComposablesPlugin = createUnplugin((options: TreeShakeComposablesPluginOptions) => {
-  const COMPOSABLE_RE = new RegExp(`($\\s+)(${options.treeShake.join('|')})(?=\\()`, 'gm')
+  /**
+   * @todo Use the options import-path to tree-shake composables in a safer way.
+   */
+  const composableNames = Object.values(options.composables).flat()
+  const COMPOSABLE_RE = new RegExp(`($\\s+)(${composableNames.join('|')})(?=\\()`, 'gm')
 
   return {
-    name: 'nuxt:server-treeshake:transform',
+    name: 'nuxt:tree-shake-composables:transform',
     enforce: 'post',
     transformInclude (id) {
       const { pathname, search } = parseURL(decodeURIComponent(pathToFileURL(id).href))

packages/schema/src/config/build.ts

@@ -108,5 +108,40 @@ export default defineUntypedSchema({
         }
       }
     },
+  },
+
+  /**
+   * Build time optimization configuration.
+   */
+  optimization: {
+    /**
+     * Tree shake code from specific builds.
+     */
+    treeShake: {
+      /**
+       * Tree shake composables from the server or client builds.
+       *
+       * @example
+       * ```js
+       * treeShake: { client: { myPackage: ['useServerOnlyComposable'] } }
+       * ```
+       */
+      composables: {
+        server: {
+          $resolve: async (val, get) => defu(val || {},
+            await get('dev') ? {} : {
+              vue: ['onBeforeMount', 'onMounted', 'onBeforeUpdate', 'onRenderTracked', 'onRenderTriggered', 'onActivated', 'onDeactivated', 'onBeforeUnmount'],
+            }
+          )
+        },
+        client: {
+          $resolve: async (val, get) => defu(val || {},
+            await get('dev') ? {} : {
+              vue: ['onServerPrefetch', 'onRenderTracked', 'onRenderTriggered'],
+            }
+          )
+        }
+      }
+    },
   }
 })

test/basic.test.ts

@@ -560,6 +560,22 @@ describe('reactivity transform', () => {
   })
 })
 
+describe('composable tree shaking', () => {
+  it('should work', async () => {
+    const html = await $fetch('/tree-shake')
+
+    expect(html).toContain('Tree Shake Example')
+
+    const page = await createPage('/tree-shake')
+    // check page doesn't have any errors or warnings in the console
+    await page.waitForLoadState('networkidle')
+    // ensure scoped classes are correctly assigned between client and server
+    expect(await page.$eval('h1', e => getComputedStyle(e).color)).toBe('rgb(255, 192, 203)')
+
+    await expectNoClientErrors('/tree-shake')
+  })
+})
+
 describe('server tree shaking', () => {
   it('should work', async () => {
     const html = await $fetch('/client')

test/fixtures/basic/composables/tree-shake.ts

@@ -0,0 +1,16 @@
+export function useServerOnlyComposable () {
+  if (process.client) {
+    throw new Error('this should not be called in the browser')
+  }
+}
+
+export function useClientOnlyComposable () {
+  // need to do some code that fails in node but not in the browser
+  if (process.server) {
+    throw new Error('this should not be called on the server')
+  }
+}
+
+export function setTitleToPink () {
+  document.querySelector('h1')!.style.color = 'pink'
+}

test/fixtures/basic/nuxt.config.ts

@@ -110,6 +110,10 @@ export default defineNuxtConfig({
         const internalParent = pages.find(page => page.path === '/internal-layout')
         internalParent!.children = newPages
       })
+    },
+    function (_, nuxt) {
+      nuxt.options.optimization.treeShake.composables.server[nuxt.options.rootDir] = ['useClientOnlyComposable', 'setTitleToPink']
+      nuxt.options.optimization.treeShake.composables.client[nuxt.options.rootDir] = ['useServerOnlyComposable']
     }
   ],
   vite: {

test/fixtures/basic/pages/tree-shake.vue

@@ -0,0 +1,13 @@
+<script lang="ts" setup>
+// server only
+useServerOnlyComposable()
+// client only
+useClientOnlyComposable()
+// can only run client side, should be tree shaken from server build
+setTitleToPink()
+</script>
+<template>
+  <div>
+    <h1>Tree Shake Example</h1>
+  </div>
+</template>