perf: lazy load rollup/parseAst

packages/vite/src/node/index.ts

@@ -1,7 +1,7 @@
 import type * as Rollup from 'rollup'
 
 export type { Rollup }
-export { parseAst, parseAstAsync } from 'rollup/parseAst'
+export { initRollupParseAst, parseAst, parseAstAsync } from './utils'
 export {
   defineConfig,
   loadConfigFromFile,

packages/vite/src/node/server/pluginContainer.ts

@@ -33,7 +33,6 @@ import fs from 'node:fs'
 import { join } from 'node:path'
 import { performance } from 'node:perf_hooks'
 import { VERSION as rollupVersion } from 'rollup'
-import { parseAst as rollupParseAst } from 'rollup/parseAst'
 import type {
   AsyncPluginHooks,
   CustomPluginOptions,
@@ -69,10 +68,12 @@ import {
   createDebugger,
   ensureWatchedFile,
   generateCodeFrame,
+  initRollupParseAst,
   isExternalUrl,
   isObject,
   normalizePath,
   numberToPos,
+  parseAst,
   prettifyUrl,
   timeFrom,
   unwrapId,
@@ -164,6 +165,8 @@ export async function createPluginContainer(
   const { getSortedPluginHooks, getSortedPlugins } =
     createPluginHookUtils(plugins)
 
+  const initRollupParseAstPromise = initRollupParseAst()
+
   const seenResolves: Record<string, true | undefined> = {}
   const debugResolve = createDebugger('vite:resolve')
   const debugPluginResolve = createDebugger('vite:plugin-resolve', {
@@ -302,7 +305,7 @@ export async function createPluginContainer(
     }
 
     parse(code: string, opts: any) {
-      return rollupParseAst(code, opts)
+      return parseAst(code, opts)
     }
 
     async resolve(
@@ -655,6 +658,7 @@ export async function createPluginContainer(
     getModuleInfo,
 
     async buildStart() {
+      await initRollupParseAstPromise
       await handleHookPromise(
         hookParallel(
           'buildStart',

packages/vite/src/node/utils.ts

@@ -17,7 +17,7 @@ import debug from 'debug'
 import type { Alias, AliasOptions } from 'dep-types/alias'
 import type MagicString from 'magic-string'
 
-import type { TransformResult } from 'rollup'
+import type { AstNode, ParseAst, ParseAstAsync, TransformResult } from 'rollup'
 import { createFilter as _createFilter } from '@rollup/pluginutils'
 import {
   CLIENT_ENTRY,
@@ -41,6 +41,46 @@ import {
 } from './packages'
 import type { CommonServerOptions } from '.'
 
+let rollupParseAst: ParseAst
+let rollupParseAstAsync: ParseAstAsync
+let rollupInited: Promise<any> | boolean = false
+export async function initRollupParseAst(): Promise<any | boolean> {
+  if (!rollupInited) {
+    const importRollupParseAst = import('rollup/parseAst')
+    rollupInited = importRollupParseAst
+    const { parseAst, parseAstAsync } = await importRollupParseAst
+    rollupParseAst = parseAst
+    rollupParseAstAsync = parseAstAsync
+    rollupInited = true
+  }
+  return rollupInited
+}
+export function parseAst(
+  code: string,
+  options?: {
+    allowReturnOutsideFunction?: boolean
+  },
+): AstNode {
+  if (!rollupInited) {
+    throw new Error(
+      `rollup/parseAst is not initialized yet, call initRollupParseAst() first`,
+    )
+  }
+  return rollupParseAst(code, options)
+}
+
+export async function parseAstAsync(
+  code: string,
+  options?: {
+    allowReturnOutsideFunction?: boolean
+  },
+): Promise<AstNode> {
+  if (rollupInited === false) {
+    await initRollupParseAst()
+  }
+  return rollupParseAstAsync(code, options)
+}
+
 /**
  * Inlined to keep `@rollup/pluginutils` in devDependencies
  */