🐛 BUG: [esinstall] duplicate export 'default' react

[oclyke]

Quick checklist

• I am using the latest version of Snowpack and all plugins.

What package manager are you using?

yarn

What operating system are you using?

macOS

Describe the bug

mixing import styles (import React from 'react' vs import { default as React } from 'react') between files unexpectedly causes an issue with [esinstall] claiming duplicate export 'default'

Steps to reproduce

easiest to clone the demo repo (link below) and follow reproduction instructions in the readme. along the lines of:

• try to build using one import style, observe failure
• switch import style
• try to build and observe success

note that the issue does not occur when using the dev server

Link to minimal reproducible example (optional)

https://github.com/oclyke-zucchini/snowpack-esinstall-react-duplicate-export-default