This repo contains the minimum needed to demonstrate the type erasure bug seen in Babel's typescript mode.

Issues

It was seen in Recharts Issue #2360.

• Babel #12578
• Babel #11464

Reproduce

Check the checked-in es6 folder to see what babel is currently emitting, or run npm run build / yarn build locally.

Expected:

SomeType is erased from es6/index.js

Actual:

SomeType is still referenced in es6/index.js

This is a problem for all the JavaScript (non-Typescript) consumers since the type does not exist in the build.

If we check es6/ModuleA.js, we can see SomeType is erased, so it's at least partly working.