fix: check exactly in proxyESM (#5512)

Author: zhangyuang

packages/playground/ssr-vue/__tests__/ssr-vue.spec.ts

@@ -4,6 +4,16 @@ import fetch from 'node-fetch'
 
 const url = `http://localhost:${port}`
 
+test('vuex can be import succeed by named import', async () => {
+  await page.goto(url + '/store')
+  expect(await page.textContent('h1')).toMatch('bar')
+
+  // raw http request
+  const storeHtml = await (await fetch(url + '/store')).text()
+  expect(storeHtml).toMatch('bar')
+})
+
+
 test('/about', async () => {
   await page.goto(url + '/about')
   expect(await page.textContent('h1')).toMatch('About')

packages/playground/ssr-vue/package.json

@@ -16,7 +16,8 @@
   "dependencies": {
     "example-external-component": "file:example-external-component",
     "vue": "^3.2.21",
-    "vue-router": "^4.0.0"
+    "vue-router": "^4.0.0",
+    "vuex": "^4.0.2"
   },
   "devDependencies": {
     "@vitejs/plugin-vue": "workspace:*",

packages/playground/ssr-vue/src/pages/Store.vue

@@ -0,0 +1,24 @@
+<template>
+  <h1>{{ foo }}</h1>
+</template>
+
+<script>
+import { createStore } from 'vuex'
+
+export default {
+  async setup() {
+    const store = createStore({
+      state: {
+        foo: 'bar'
+      }
+    })
+    return store.state
+  }
+}
+</script>
+
+<style scoped>
+h1 {
+  color: red;
+}
+</style>

packages/vite/src/node/ssr/ssrModuleLoader.ts

@@ -257,7 +257,7 @@ function proxyESM(id: string, mod: any) {
   return new Proxy(mod, {
     get(mod, prop) {
       if (prop === 'default') return defaultExport
-      return mod[prop]
+      return mod[prop] ?? defaultExport?.[prop]
     }
   })
 }