Impossible to add pluralizationRules via the vueI18n options

Version

v5.3.0

Reproduction link

Not really needed

Steps to reproduce

1. In nuxt.config.js, within the options for the nuxt-i18n module, add a vuei18n option
2. Add pluralizationRules: {'en': function(choice, choicesLength) { return 0 }} object
3. run npm run dev

What is expected ?

The generated .nuxt/nuxt-i18n/plugin.main.js file should initialize new VueI18n with pluralizationRules: {'en': function(choice, choicesLength) { return 0 }} parameter

What is actually happening?

pluralizationRules is an empty object

Additional comments?

This happens because the vuei18n options get stringified using JSON.stringify here. The result of JSON.stringify({foo: function() {return 'bar'}}) is an empty object as the method serializes function as null value as you can see here

The option to initialize VueI18n with pluralization rules was added recently (see discussion)

<div align="right">_{This bug report is available on Nuxt community (#c209)}</div>

[pampi848]

@lukaVarga try pluralRules instead of pluralizationRules

[rchl]

Passing functions through module options would require serialization of function and that is, while possible, generally discouraged by core team. Better option is to support external configuration file that would be required by the module. Then you can use functions without problems.

But I agree it should be re-opened.