transformer-typescript-tsc multiple default exports

[shulcsm]

🐛 bug report

ESM builds with transformer-typescript-tsc@2.0.0-nightly.690 and parcel@2.0.0-nightly.688 result in multiple default exports

🤔 Expected Behavior

Valid package

😯 Current Behavior

export{o as default,s as ButtonBase,i as default,b as Button,u as default}

🔦 Context

I'm not smart enough to debug this but suspect it has something to do with hoisting.
Default (babel?) transform seems to be working just fine.

💻 Code Sample

https://github.com/shulcsm/parceldemo

[shulcsm]

Update: looks like it has nothing to do with transformer-typescript-tsc in particular, just encountered similar issue with babel transform on slightly different layout.

export * from files that only have type exports seems to be the cause.

[devongovett]

Possibly related to #6361