class RuboCop::Cop::Performance::CompareWithBlock

def on_block(node)
  compare?(node) do |send, var_a, var_b, body|
    replaceable_body?(body, var_a, var_b) do |method, args_a, args_b|
      return unless slow_compare?(method, args_a, args_b)
      range = compare_range(send, node)
      add_offense(range, message: message(send, method, var_a, var_b, args_a)) do |corrector|
        replacement = if method == :[]
                        "#{REPLACEMENT[send.method_name]} { |a| a[#{args_a.first.source}] }"
                      else
                        "#{REPLACEMENT[send.method_name]}(&:#{method})"
                      end
        corrector.replace(range, replacement)
      end
    end
  end
end