UnoCSS version

65.5.0

Describe the bug

Example code:

import { CountableSet } from '@unocss/core';

const set = new CountableSet(['foo']);
console.log('[set]', set);
console.log('[count]', set.getCount('foo'));

Output:

[set] CountableSet(1) [Set] { 'foo', _map: Map(0) {} }
[count] 0

Even though the intended behavior is confirmed by the following test:

this actually depends on how class field _map: Map<K, number> is transformed. On Vitest, it's transformed with typescript useDefineForClassFields: false semantics and it works, but the published version is transpiled with standard class field semantics and it breaks current implementation of CountableSet constructor:

Internally, new CountableSet() is always used without constructor arguments, so the issue haven't probably manifested anywhere.

Side note: I was checking the test failure when using rolldown-vite and the code is broken even on Vitest due to oxc transform oxc-project/oxc#9192. Then I just noticed the published @unocss/core is also broken, so I ended up reporting it here.

Reproduction

https://stackblitz.com/edit/vitejs-vite-wgp96mef?file=repro.js

System Info

(stackblitz)

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