types: locale property from nuxtApp.$i18n is string & computedRef<string>

[huang-julien]

Environment

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• Operating System: Windows_NT
• Node Version: v18.15.0
• Nuxt Version: 3.4.1
• Nitro Version: 2.3.3
• Package Manager: pnpm@8.6.0
• Builder: vite
• User Config: -
• Runtime Modules: -
• Build Modules: -

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Reproduction

Describe the bug

when using useNuxtApp().$i18n.locale, the returned type is string & WritableComputedRef<string> which can be very confusing for developers and even linters as it does not warns that it is an object when migrating from i18n vue 2, Nuxt 2 or bridge.

Additional context

No response

Logs

No response

[kazupon]

This issue is related to vue-i18n v9.
vue-i18n v9 has a Legacy API (options API) style and a composition API style.
vue-i18n should support the type inference for both API styles.
ref: intlify/vue-i18n#1113 (comment)

BTW, nuxt i18n module allows you to change the type behavior of $i18n with the types option.
https://v8.i18n.nuxtjs.org/options/misc#types