class RuboCop::Cop::Layout::EmptyLines

def autocorrect(range)
  ->(corrector) { corrector.remove(range) }
end

def each_extra_empty_line(lines)
  prev_line = 1
  lines.each do |cur_line|
    if exceeds_line_offset?(cur_line - prev_line)
      # we need to be wary of comments since they
      # don't show up in the tokens
      ((prev_line + 1)...cur_line).each do |line|
        next unless previous_and_current_lines_empty?(line)
        yield source_range(processed_source.buffer, line, 0)
      end
    end
    prev_line = cur_line
  end
end

def exceeds_line_offset?(line_diff)
  line_diff > LINE_OFFSET
end

def investigate(processed_source)
  return if processed_source.tokens.empty?
  lines = Set.new
  processed_source.tokens.each do |token|
    lines << token.pos.line
  end
  each_extra_empty_line(lines.sort) do |range|
    add_offense(range, range)
  end
end

def previous_and_current_lines_empty?(line)
  processed_source[line - 2].empty? && processed_source[line - 1].empty?
end