fix(plugin-react): apply babel.plugins to project files only

packages/plugin-react/src/index.ts

@@ -108,36 +108,17 @@ export default function viteReact(opts: Options = {}): PluginOption[] {
         []
 
       if (/\.(mjs|[tj]sx?)$/.test(extension)) {
-        const plugins = [...userPlugins]
+        const isJSX = extension.endsWith('x')
+        const isNodeModules = id.includes('/node_modules/')
+        const isProjectFile =
+          !isNodeModules && (id[0] === '\0' || id.startsWith(projectRoot + '/'))
 
-        const parserPlugins: typeof userParserPlugins = [
-          ...userParserPlugins,
-          'importMeta',
-          // This plugin is applied before esbuild transforms the code,
-          // so we need to enable some stage 3 syntax that is supported in
-          // TypeScript and some environments already.
-          'topLevelAwait',
-          'classProperties',
-          'classPrivateProperties',
-          'classPrivateMethods'
-        ]
-
-        if (!extension.endsWith('.ts')) {
-          parserPlugins.push('jsx')
-        }
-
-        const isTypeScript = /\.tsx?$/.test(extension)
-        if (isTypeScript) {
-          parserPlugins.push('typescript')
-        }
-
-        const isNodeModules = id.includes('node_modules')
+        let plugins = isProjectFile ? [...userPlugins] : []
 
         let useFastRefresh = false
         if (!skipFastRefresh && !ssr && !isNodeModules) {
           // Modules with .js or .ts extension must import React.
-          const isReactModule =
-            extension.endsWith('x') || code.includes('react')
+          const isReactModule = isJSX || code.includes('react')
           if (isReactModule && filter(id)) {
             useFastRefresh = true
             plugins.push([
@@ -148,16 +129,16 @@ export default function viteReact(opts: Options = {}): PluginOption[] {
         }
 
         let ast: t.File | null | undefined
-        if (isNodeModules || extension.endsWith('x')) {
+        if (!isProjectFile || isJSX) {
           if (useAutomaticRuntime) {
             // By reverse-compiling "React.createElement" calls into JSX,
             // React elements provided by dependencies will also use the
             // automatic runtime!
-            const [restoredAst, isCommonJS] = isNodeModules
+            const [restoredAst, isCommonJS] = !isProjectFile
               ? await restoreJSX(babel, code, id)
               : [null, false]
 
-            if (!isNodeModules || (ast = restoredAst)) {
+            if (isProjectFile || (ast = restoredAst)) {
               plugins.push([
                 await loadPlugin(
                   '@babel/plugin-transform-react-jsx' +
@@ -174,7 +155,7 @@ export default function viteReact(opts: Options = {}): PluginOption[] {
                 plugins.push(babelImportToRequire)
               }
             }
-          } else if (!isNodeModules) {
+          } else if (isProjectFile) {
             // These plugins are only needed for the classic runtime.
             if (!isProduction) {
               plugins.push(
@@ -191,7 +172,40 @@ export default function viteReact(opts: Options = {}): PluginOption[] {
           }
         }
 
-        const isReasonReact = extension.endsWith('.bs.js')
+        // Plugins defined through this Vite plugin are only applied
+        // to modules within the project root, but "babel.config.js"
+        // files can define plugins that need to be applied to every
+        // module, including node_modules and linked packages.
+        const shouldSkip =
+          !plugins.length &&
+          !opts.babel?.configFile &&
+          !(isProjectFile && opts.babel?.babelrc)
+
+        if (shouldSkip) {
+          return // Avoid parsing if no plugins exist.
+        }
+
+        const parserPlugins: typeof userParserPlugins = [
+          ...userParserPlugins,
+          'importMeta',
+          // This plugin is applied before esbuild transforms the code,
+          // so we need to enable some stage 3 syntax that is supported in
+          // TypeScript and some environments already.
+          'topLevelAwait',
+          'classProperties',
+          'classPrivateProperties',
+          'classPrivateMethods'
+        ]
+
+        if (!id.endsWith('.ts')) {
+          parserPlugins.push('jsx')
+        }
+
+        if (/\.tsx?$/.test(id)) {
+          parserPlugins.push('typescript')
+        }
+
+        const isReasonReact = id.endsWith('.bs.js')
 
         const babelOpts: TransformOptions = {
           babelrc: false,

packages/plugin-react/src/jsx-runtime/restore-jsx.ts

@@ -4,13 +4,25 @@ type RestoredJSX = [result: t.File | null | undefined, isCommonJS: boolean]
 
 let babelRestoreJSX: Promise<PluginItem> | undefined
 
+const jsxNotFound: RestoredJSX = [null, false]
+
 /** Restore JSX from `React.createElement` calls */
 export async function restoreJSX(
   babel: typeof import('@babel/core'),
   code: string,
   filename: string
 ): Promise<RestoredJSX> {
+  // Avoid parsing the optimized react-dom since it will never
+  // contain compiled JSX and it's a pretty big file (800kb).
+  if (filename.includes('/.vite/react-dom.js')) {
+    return jsxNotFound
+  }
+
   const [reactAlias, isCommonJS] = parseReactAlias(code)
+  if (!reactAlias) {
+    return jsxNotFound
+  }
+
   const reactJsxRE = new RegExp(
     '\\b' + reactAlias + '\\.(createElement|Fragment)\\b',
     'g'
@@ -24,7 +36,7 @@ export async function restoreJSX(
   })
 
   if (!hasCompiledJsx) {
-    return [null, false]
+    return jsxNotFound
   }
 
   // Support modules that use `import {Fragment} from 'react'`