rabbitmq-server/deps/rabbitmq_cli/lib/rabbitmq/cli/formatters/erlang.ex

## The contents of this file are subject to the Mozilla Public License
## Version 1.1 (the "License"); you may not use this file except in
## compliance with the License. You may obtain a copy of the License
## at http://www.mozilla.org/MPL/
##
## Software distributed under the License is distributed on an "AS IS"
## basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
## the License for the specific language governing rights and
## limitations under the License.
##
## The Original Code is RabbitMQ.
##
## The Initial Developer of the Original Code is GoPivotal, Inc.
## Copyright (c) 2007-2017 Pivotal Software, Inc.  All rights reserved.

defmodule RabbitMQ.CLI.Formatters.Erlang do
  @behaviour RabbitMQ.CLI.FormatterBehaviour

  def format_output(output, _) do
    :io_lib.format("~p", [output])
    |> to_string
  end

  def format_stream(stream, options) do
    elements = Stream.scan(stream, :empty,
      fn
        ({:error, msg}, _) ->
          {:error, msg};
        (element, previous) ->
          separator = case previous do
                        :empty -> "";
                        _      -> ","
                      end
        format_element(element, separator, options)
      end)
    Stream.concat([["["], elements, ["]"]])
  end

  def format_element(val, separator, options) do
    separator <> format_output(val, options)
  end
end