Incorrect SSR transform

[egoist]

⚠️ IMPORTANT ⚠️ Please check the following list before proceeding. If you ignore this issue template, your issue will be directly closed.

• Read the docs.
• Use Vite >=2.0. (1.x is no longer supported)
• If the issue is related to 1.x -> 2.0 upgrade, read the Migration Guide first.

Describe the bug

Incorrect code transform by vite.ssrLoadModule.

Reproduction

Test:

import { ssrTransform } from 'vite/src/node/ssr/ssrTransform'
;(async () => {
  console.log('// Code 1:')
  const result = await ssrTransform(`
  import {createApp} from 'vue';
  export {createApp}
  `)

  console.log(result.code)

  console.log('\n// Code 2:')

  const result2 = await ssrTransform(`
  export * from 'vue'
  `)

  console.log(result2.code)
})()

Output:

// Code 1:

  const __vite_ssr_import_0__ = __vite_ssr_import__("vue")

  __vite_ssr_import_0__.createApp
  
Object.defineProperty(__vite_ssr_exports__, "createApp", { get(){ return createApp }})

// Code 2:

  const __vite_ssr_import_0__ = __vite_ssr_import__("vue")
export * from 'vue'
  
__vite_ssr_exportAll__(__vite_ssr_import_0__)

System Info

• vite version: 2.0.0-beta.37
• Operating System:
• Node version:
• Package manager (npm/yarn/pnpm) and version:

Logs (Optional if provided reproduction)

1. Run vite or vite build with the --debug flag.
2. Provide the error log here.