Method: Cmds#capture

Defined in:
lib/cmds/capture.rb

#capture(*args, **kwds, &input_block) ⇒ Cmds::Result Also known as: call

executes the command and returns a Result with the captured outputs.

Parameters:

  • *args (Array<Object>) —

    positional parameters to append to those in @args for rendering into the command string.

  • **kwds (Hash{Symbol => Object}) —

    keyword parameters that override those in @kwds for rendering into the command string.

  • &input_block (#call) —

    optional block that returns a string or readable object to override @input.

Returns:

  • (Cmds::Result) —

    result of execution with command string, status, stdout and stderr.



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# File 'lib/cmds/capture.rb', line 21

def capture *args, **kwds, &input_block
  logger.trace "entering Cmds#capture",
    args: args,
    kwds: kwds,
    input: input
  
  # extract input from block via `call` if one is provided,
  # otherwise default to instance variable (which may be `nil`)
  input = input_block.nil? ? input : input_block.call
  
  logger.trace "configured input",
    input: input
  
  # strings output will be concatenated onto
  out = ''
  err = ''

  logger.trace "calling Cmds.spawn..."
  
  status = spawn(*args, **kwds) do |io|
    # send the input to stream, which sends it to spawn
    io.in = input

    # and concat the output lines as they come in
    io.on_out do |line|
      out += line
    end

    io.on_err do |line|
      err += line
    end
  end
  
  logger.trace "Cmds.spawn completed",
    status: status

  # build a Result
  # result = Cmds::Result.new cmd, status, out_reader.value, err_reader.value
  result = Cmds::Result.new last_prepared_cmd, status, out, err

  # tell the Result to assert if the Cmds has been told to, which will
  # raise a SystemCallError with the exit status if it was non-zero
  result.assert if assert

  return result
end