A short blog on some tips to cleanly pluralize and translate content in Rails.

Even after 12 years of working with Rails, I still keep discovering these small but extremely useful utilities. Today was one such day and I'll share a couple tips related to pluralization and translations.

Scoped translations

Translations can get deeply nested leading to long strings:

I18n.t("activerecord.errors.messages.record_invalid")
I18n.t("users.profile.popup.title")

Note that you have to read the entire string to understand what this translation is for, because the real key is last part (record_invalid and title).

Rails allows specifying scope on translation which makes it better to read:

I18n.t(:record_invalid, scope: [:activerecord, :errors, :messages])
I18n.t(:title, scope: [:users, :profile, :popup])

At first glance we see this translation is for record_invalid and title.

Pluralized translations

The pluralize helper method is pretty commonly used:

pluralize("day")   # => "days"
pluralize("hour")  # => "hours"

But what if we need to support multiple languages?

en:
  items:
    zero: Zero items
    one: One item
    other: Many items

es:
  items:
    zero: Cero artículos
    one: Un artículo
    other: Muchos artículos

if items.count == 0
  I18n.t("items.zero")
elsif items.count == 1
  I18n.t("items.one")
else
  I18n.t("items.other")
end

Instead Rails provides a handy :count helper:

I18n.t("items", count: items.count)

More details in Rails guides.