# File lib/test/unit/data.rb, line 218
          def load(file_name)
            case File.extname(file_name).downcase
            when ".csv"
              load_csv(file_name)
            when ".tsv"
              load_tsv(file_name)
            else
              raise ArgumentError, "unsupported file format: <#{file_name}>"
            end
          end