updated karmi's gist with support for empty brackets, like "Users"[]

gibberish.rake

# Add your own tasks in files placed in lib/tasks ending in .rake,
# for example lib/tasks/capistrano.rake, and they will automatically be available to Rake.
require(File.join(File.dirname(__FILE__), 'config', 'boot'))

require 'rake'
require 'rake/testtask'
require 'rake/rdoctask'
require 'tasks/rails'
require 'fileutils'
 
namespace :localize do
  desc "Extract all texts prepared to be translated from Ruby source"
  task :extract do
    count, keys, out = 0, [], "# Localization dictionary for the 'Gibberish' plugin (#{RAILS_ROOT.split('/').last})\n\n"
    
    Dir["#{RAILS_ROOT}/app/**/*"].sort.each do |path|
        unless ( matches = File.new(path).read.scan(/['"]([^'"\n]*)['"]\[\:?([a-z1-9\_]*)\]/) ).empty?
          print "."
          out << "# -- #{path.gsub(/#{RAILS_ROOT}/,'')}:\n"          
          matches.each do |m| 
            out << "#{m[1].blank? ? m[0].downcase : m[1]}: #{m[0]}\n" unless keys.include? m[1]
            keys << m[1]
          end
          out << "\n"                                      
          count +=1
        end if FileTest.file? path
    end
    FileUtils.mkdir_p File.join(RAILS_ROOT, 'lang') # Ensure we have lang dir
    File.open( File.join(RAILS_ROOT, 'lang', 'new_language.yml'), "w") { |file| file << out } 
    puts "\nProcessed #{count} files and dumped YAML into #{RAILS_ROOT}/lang/new_language.yml"
  end
end