class ActiveRecord::FixtureSet

def create_fixtures(fixtures_directory, fixture_set_names, class_names = {}, config = ActiveRecord::Base, &block)
  fixture_set_names = Array(fixture_set_names).map(&:to_s)
  class_names = ClassCache.new class_names, config
  # FIXME: Apparently JK uses this.
  connection = block_given? ? block : lambda { ActiveRecord::Base.connection }
  fixture_files_to_read = fixture_set_names.reject do |fs_name|
    fixture_is_cached?(connection.call, fs_name)
  end
  if fixture_files_to_read.any?
    fixtures_map = read_and_insert(
      fixtures_directory,
      fixture_files_to_read,
      class_names,
      connection,
    )
    cache_fixtures(connection.call, fixtures_map)
  end
  cached_fixtures(connection.call, fixture_set_names)
end