CSV::Parser::InputsScanner#keep_end

# File tmp/rubies/ruby-3.3.0/lib/csv/parser.rb, line 181
def keep_end
  # trace(__method__, :start)
  scanner, start, buffer = @keeps.pop
  if scanner == @scanner
    keep = @scanner.string.byteslice(start, @scanner.pos - start)
  else
    keep = @scanner.string.byteslice(0, @scanner.pos)
  end
  if buffer
    buffer << keep
    keep = buffer
  end
  # trace(__method__, :done, keep)
  keep
end