ActiveRecordのi18nの定義漏れをテストする

missing_model_i18n_spec.rb

# frozen_string_literal: true

RSpec.describe 'ActiveRecord i18n' do
  let(:table_names) { ActiveRecord::Base.connection.tables }

  let(:models) do
    table_names.map do |table_name|
      table_to_model(table_name)
    rescue NameError
      nil
    end.compact
  end

  let(:missing_locale) do
    "Missing #{SecureRandom.uuid}"
  end

  def table_to_model(table_name)
    table_name.singularize.classify.constantize
  end

  describe 'Model' do
    it 'is localizable' do
      missing_locales = []

      models.each do |model|
        localized = model.model_name.human(default: missing_locale)
        missing_locales.push(model) if localized == missing_locale
      end

      expect(missing_locales).to be_empty, -> {
        result = missing_locales.map { |model| "#{model.model_name.element}: " }

        <<~EOS
          Missing model name locales. Please add locales to config/locales/models/defaults/*.yml

          #{result.join("\n")}
        EOS
      }
    end
  end

  describe 'Columns' do
    def extract_column_names(model)
      # typeは翻訳しないことが多いので無視する
      ignore_columns = ['type']

      # 外部キーの_idは翻訳しないので無視する
      foreign_keys = model.reflect_on_all_associations(:belongs_to).map(&:foreign_key)

      # GeneratedColumnは隠蔽されていることが多いので無視する
      generated_columns = model.columns.select(&:virtual?).map(&:name)

      model.column_names - ignore_columns - foreign_keys - generated_columns
    end

    it 'is localizable' do
      missing_locales = Hash.new { |h, k| h[k] = [] }

      models.each do |model|
        extract_column_names(model).each do |column_name|
          localized = model.human_attribute_name(column_name, default: missing_locale)
          missing_locales[model].push(column_name) if localized == missing_locale
        end
      end

      expect(missing_locales).to be_empty, -> {
        result = missing_locales.map do |model, attributes|
          "#{model.name} [#{attributes.join(', ')}]"
        end

        <<~EOS
          Missing locales. Please add locales to config/locales/models/**/*.yml

          #{result.join("\n")}
        EOS
      }
    end
  end

  describe 'Associations' do
    it 'is localizable' do
      missing_locales = Hash.new { |h, k| h[k] = [] }

      models.each do |model|
        reflections = model.reflections.select do |_, reflection|
          reflection.options.key?(:dependent)
        end

        reflections.each_key do |association_name|
          localized = model.human_attribute_name(association_name, default: missing_locale)
          missing_locales[model].push(association_name) if localized == missing_locale
        end
      end

      expect(missing_locales).to be_empty, -> {
        result = missing_locales.map do |model, attributes|
          <<~EOS
            activerecord:
              attributes:
                #{model.model_name.singular}:
            #{attributes.map { |name| "      #{name}:" }.join("\n")}
          EOS
        end

        <<~EOS
          Missing association locales.

          #{result.join("\n")}
        EOS
      }
    end
  end
end