short script that finds and reports missing translation keys

find_missing_translations.rake

require "yaml"

desc "Find missing translations"
task :find_missing_translations do
  base_locale = 'en'
  locale_to_translate_in = 'zh-CN'

  english_texts = YAML::load(File.read(File.join(RAILS_ROOT, 'config', 'locales', base_locale+".yml")))
  translations = YAML::load(File.read(File.join(RAILS_ROOT, 'config', 'locales', locale_to_translate_in+".yml")))

  puts "The following translations for '#{locale_to_translate_in}' are missing:"
  find_missing_keys(english_texts[base_locale], translations[locale_to_translate_in])
end

def find_missing_keys(first_hash, second_hash, prefix="")
  first_hash.keys.each do |key|
    if (second_hash.keys.include?(key))
      # exists, go deeper if it's a hash
      if ((first_hash[key].class == Hash) && (second_hash[key].class == Hash))
       find_missing_keys(first_hash[key], second_hash[key], prefix+"#{key}:")
      end
    else
      # doesn't exist, report
      puts " #{prefix}#{key}:"
    end
  end
end