cannot use kebab-case keys from .json file default exports

[alexzhang1030]

Environment

stackblitz
unbuild: ^1.1.1
node: 16.14.2

Reproduction

https://stackblitz.com/edit/node-z61fts?file=index.js

Describe the bug

When import a kabab-case field from json file.

The result after the build is incorrect.

Please see reproduction and execute npm run build, and see dist/index.js.mjs.

I think this is an upstream error from rollup. But I cannot reproduce it by using rollup.

Additional context

No response

Logs

No response

[zoeyzhao19]

@alexzhang1030 , it is due to @rollup/plugin-json try to make identitier legal through

const makeLegalIdentifier = function makeLegalIdentifier(str) {
    let identifier = str
        .replace(/-(\w)/g, (_, letter) => letter.toUpperCase())
        .replace(/[^$_a-zA-Z0-9]/g, '_');
    if (/\d/.test(identifier[0]) || forbiddenIdentifiers.has(identifier)) {
        identifier = `_${identifier}`;
    }
    return identifier || '_';
};

So it replace something-idk to somethingIdk, that's why the named export code in the bundle file doesn't contain the kebab-case field. Related to here

[alexzhang1030]

@alexzhang1030 , it is due to @rollup/plugin-json try to make identitier legal through

const makeLegalIdentifier = function makeLegalIdentifier(str) {
    let identifier = str
        .replace(/-(\w)/g, (_, letter) => letter.toUpperCase())
        .replace(/[^$_a-zA-Z0-9]/g, '_');
    if (/\d/.test(identifier[0]) || forbiddenIdentifiers.has(identifier)) {
        identifier = `_${identifier}`;
    }
    return identifier || '_';
};

So it replace something-idk to somethingIdk, that's why the named export code in the bundle file doesn't contain the kebab-case field. Related to here

I think so, let's track this issue.