`[Vue Router warn]: The Matcher cannot resolve relative paths` when `baseURL` and strategy: "prefix" is set

[ItsuoSano]

Environment

---

• Operating System: Darwin
• Node Version: v22.21.1
• Nuxt Version: 4.2.1
• CLI Version: 3.30.0
• Nitro Version: 2.12.9
• Package Manager: pnpm@9.15.9
• Builder: -
• User Config: compatibilityDate, devtools, modules, i18n, typescript, app, experimental
• Runtime Modules: @nuxtjs/i18n@10.2.1
• Build Modules: -

---

Reproduction

reproduction

set nuxt.config.ts

app: {
  baseURL: '/12345'
}

and

i18n:{
  strategy: 'prefix'
}

1. Open stackblitz reproduction page
2. Open the page in new tab
3. Reload the page.

console shows WARN [Vue Router warn]: The Matcher cannot resolve relative paths but received "345/en". Unless you directly called matcher.resolve("345/en"), this is probably a bug in vue-router. Please open an issue at https://github.com/vuejs/router/issues/new/choose.

Describe the bug

I believe the root cause of this bug is that app.baseURL (defined in nuxt.config.ts) is not taken into account when calculating the path.

i18n/src/runtime/server/plugin.ts

Line 158 in 15bb7bb

const path = (pathLocale && url.pathname.slice(pathLocale.length + 1)) ?? url.pathname

Proposed Fix: I suggest modifying the code as follows:

const path = (pathLocale && event.path.slice(pathLocale.length + 1)) ?? event.path

sorry, I haven't checked for potential side effects.

Additional context

No response

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