TS2339: Property 'slice' does not exist on type 'U[keyof U]'

[lewebsimple]

Checks

• Not a duplicate.
• Not a question, feature request, or anything other than a bug report directly related to Splide. Use Discussions for these topics: https://github.com/Splidejs/splide/discussions

Version

v0.6.12

Description

I get the TS error mentioned in the title when building for production in a Nuxt 3 project using @splidejs/vue-splide:

node_modules/.pnpm/@[email protected]/node_modules/@splidejs/vue-splide/src/js/utils/merge/merge.ts:39:29 - error TS2339: Property 'slice' does not exist on type 'U[keyof U]'.

39       merged[ key ] = value.slice();
                               ~~~~~

It works in development mode.

Reproduction Link

No response

Steps to Reproduce

1. pnpx nuxi init test-splide
2. pnpm add @splidejs/vue-splide
3. Add the following in plugins/splide.ts:

import "@splidejs/vue-splide/css";
import VueSplide from "@splidejs/vue-splide";
export default defineNuxtPlugin((nuxtApp) => {
  nuxtApp.vueApp.use(VueSplide);
});

4. Add the <Splide> component in app.vue
5. Set typescript: { typeCheck; 'build' } in nuxt.config.ts
6. pnpm build

Expected Behaviour

It should build without errors.