# File lib/chef/run_list.rb, line 136
    def expansion_for_data_source(data_source, opts={})
      data_source = 'disk' if Chef::Config[:solo]
      case data_source.to_s
      when 'disk'
        RunListExpansionFromDisk.new(@run_list_items)
      when 'server'
        RunListExpansionFromAPI.new(@run_list_items, opts[:rest])
      when 'couchdb'
        RunListExpansionFromCouchDB.new(@run_list_items, opts[:couchdb])
      end
    end