Unexpected output from an exported mergeable enum

[magic-akari]

Description

The output of sucrase is not valid JavaScript code.

Input

export enum E {
  A = 1
}
export enum E {
  B = 2
}

Playground

https://sucrase.io/#transforms=typescript&compareWithBabel=false&compareWithTypeScript=true&code=export%20enum%20E%20%7B%0A%20%20A%20%3D%201%0A%7D%0Aexport%20enum%20E%20%7B%0A%20%20B%20%3D%202%0A%7D%0A

[alangpierce]

Thanks for reporting! And sorry for the delay.

This appears to be a case where transpiling requires tracking identifier usage across the file, which is a pain and may hurt performance, but should be possible for Sucrase. The high-level plan is to keep the first export and to remove the export for later enums of the same name.

[magic-akari]

Anoter case about mergeable enum.

enum E {
  A = 1
}
enum E {
  B = A
}

https://sucrase.io/#transforms=typescript&compareWithBabel=false&compareWithTypeScript=true&code=enum%20E%20%7B%0A%20%20A%20%3D%201%0A%7D%0Aenum%20E%20%7B%0A%20%20B%20%3D%20A%0A%7D