Custom pluralization rule is not working

[RollingTL]

Reporting a bug?

Hi,
I am trying to use custom pluralization function but it seems it is not working as expected:

The result is:

<p>1 машина</p>
<p>2 машины</p>
<p>4 машины</p>
<p>12 машины</p>
<p>21 машины</p>

Expected behavior

<p>1 машина</p>
<p>2 машины</p>
<p>4 машины</p>
<p>12 машин</p>
<p>21 машина</p>

12 and 21 result is wrong.

Reproduction

https://github.com/RollingTL/Testing-intlify-vue-i18n-next-custom-pluralization

System Info

Mac OS

Screenshot

No response

Additional context

No response

Validations

• Read the Contributing Guidelines
• Read the Documentation
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.
• Check that this is a concrete bug. For Q&A open a GitHub Discussion
• The provided reproduction is a minimal reproducible example of the bug.

[RollingTL]

I played with pluralization function and I think that it never called.
And one question what is the purpose of second and third argument? (choicesLength, orgRule)

[RollingTL]

After reading sources I have found the problem
Instead of pluralizationRules as in documentation the option should be pluralRules.

const i18n = createI18n({
  locale: 'ru',
  // the custom rules here ...
  **pluralRules**: {
    ru: customRule
  },
  messages: {
    ru: {
      car: '0 машин | {n} машина | {n} машины | {n} машин',
      banana: 'нет бананов | {n} банан | {n} банана | {n} бананов'
    }
  }
})

It is necessary to change documentation to fit source or source to fit documentation.

[kazupon]

Thank you for your feedback.

About custom pluralization, vue-i18n@v9.x or later have a breaking change
You need to check docs here:
https://vue-i18n.intlify.dev/guide/migration/breaking.html#pluralization-api-return-value

In composition API, we don't mention custom pluralization.
We should improve the docs about custom pluralization.
https://vue-i18n.intlify.dev/guide/advanced/composition.html#pluralization

[RollingTL]

thank you for prompt reaction.

[FADL285]

The problem is still found instead of 'pluralizationRules' as in documentation it should be 'pluralRules'

or change the code to be pluralizationRules

[mewforest]

OMG There is still an issue in documentation! 😮

The problem is still found instead of 'pluralizationRules' as in documentation it should be 'pluralRules'

[nulen]

Yup, please fix it, chat gpt also suggests "pluralizationRules"

[BobbieGoede]

As described in the documentation both pluralizationRules and pluralRules are the correct keys, it just depends on whether you're using the Composition API or the Options API.

• pluralizationRules (Options/legacy API)
• pluralRules (Composition API)

See https://vue-i18n.intlify.dev/guide/essentials/pluralization.html#custom-pluralization and compare highlighted lines in breaking changes with highlighted lines in breaking changes.

If you feel like this could be documented in a better way feel free to open a PR!

Yup, please fix it, chat gpt also suggests "pluralizationRules"

As for this, we have no control over what information chat GPT uses and it's your own responsibility to verify its output.

[Divensky]

@RollingTL earlier asked about the purpose of second and third argument (choicesLength, orgRule).

I found an explanation of the choicesLength as an overall amount of available choices. But I did not find an explanation of orgRule anywhere.

Could anyone help with this explanation? I wonder if it might help to customize rule sets for different words. Within a Slavic language, different words have different plural forms... choicesLength might help as workaround but I wonder if there is a direct way to set a rule for a specific group of words in that locale.