Support const enum?

[Tofandel]

I have the same issue as #1650 which is locked (I really don't think it's helpful to lock old issues as this creates thread disparity and hard to find information and also hinders discussion)

And the given reason is that vite transpiles to js without types, but I also tried ts-mocha which is also transpile only by default and yet const enum works there, so what are they doing differently for this to work?

[sheremet-va]

Vite uses esbuild which doesn't support const enum.

[Tofandel]

See: evanw/esbuild#128 (comment)

Esbuild does support const enum, I just think it's because of isolatedModules of vite and export declare const enum instead of export const enum

So maybe we can remove the declare in the vue source or maybe add a vite plugin to transform this kind of enums to enums that can be understood by esbuild without types

[sheremet-va]

Vitest does no additional processing otherwise there will be a difference between dev and tests for people who use Vite.

If you want any changes to how files are transformed, you can start discussion in Vite repo.

[yangmingshan]

Vitest didn't support const enum, but it works fine with Vue which has many const enum, how did this happened? Do you have any clue? @sheremet-va

[yangmingshan]

I figure it out, esbuild can handle const enum, but it can't handle package's const enum, because the const enum only exist in the package's type file.

I opened a feature request in esbuild: evanw/esbuild#3359, please upvote if you want it too.