Checklist

• I have tried restarting my IDE and the issue persists.
• I have read the FAQ and my problem is not listed.

Tell us about your environment

• ESLint version: 8.45.0
• eslint-plugin-vue version: 9.15.1
• Node version: v20.3.1
• Operating System: Linux

Please show your full configuration:

/* eslint-env node */
require('@rushstack/eslint-patch/modern-module-resolution')

const {defineConfig} = require('eslint-define-config')

module.exports = defineConfig({
  root: true,
  'extends': [
    'plugin:vue/vue3-essential',
    'eslint:recommended',
    '@vue/eslint-config-typescript',
    '@vue/eslint-config-prettier/skip-formatting'
  ],
  parserOptions: {
    ecmaVersion: 'latest'
  },
  rules: {
    'vue/require-valid-default-prop': 'error'
  }
})

What did you do?

<script setup lang="ts">
import type { Foo } from '../types';

// type Foo = boolean

const props = withDefaults(defineProps<{
  msg?: Foo | 'foo'
}>(), {
  msg: false, // Errors here `Type of the default value for 'msg' prop must be a string.`
})
</script>

<template>
  <div class="greetings">
  </div>
</template>

export type Foo = boolean

What did you expect to happen?

No error, this is valid syntax post Vue 3.3

What actually happened?

Type of the default value for 'msg' prop must be a string.

This is incorrect, as this is correct post Vue 3.3.

Repository to reproduce this issue

https://github.com/VividLemon/vue-eslint-require-default-prop-bug