# File lib/hiera/backend.rb, line 117
      def datasourcefiles(backend, scope, extension, override=nil, hierarchy=nil)
        datadir = Backend.datadir(backend, scope)
        Backend.datasources(scope, override, hierarchy) do |source|
          Hiera.debug("Looking for data source #{source}")
          file = datafile_in(datadir, source, extension)

          if file
            yield source, file
          end
        end
      end