Contents

# frozen_string_literal: true

module RuboCop
  module Cop
    module Performance
      # This cop is used to identify usages of `reverse.each` and
      # change them to use `reverse_each` instead.
      #
      # @example
      #   # bad
      #   [].reverse.each
      #
      #   # good
      #   [].reverse_each
      class ReverseEach < Base
        include RangeHelp
        extend AutoCorrector

        MSG = 'Use `reverse_each` instead of `reverse.each`.'
        RESTRICT_ON_SEND = %i[each].freeze
        UNDERSCORE = '_'

        def_node_matcher :reverse_each?, <<~MATCHER
          (send $(send _ :reverse) :each)
        MATCHER

        def on_send(node)
          reverse_each?(node) do |receiver|
            location_of_reverse = receiver.loc.selector.begin_pos
            end_location = node.loc.selector.end_pos

            range = range_between(location_of_reverse, end_location)

            add_offense(range) do |corrector|
              corrector.replace(replacement_range(node), UNDERSCORE)
            end
          end
        end

        private

        def replacement_range(node)
          range_between(node.loc.dot.begin_pos, node.loc.selector.begin_pos)
        end
      end
    end
  end
end

Version data entries

2 entries across 2 versions & 1 rubygems

Version	Path
rubocop-performance-1.9.1	lib/rubocop/cop/performance/reverse_each.rb
rubocop-performance-1.9.0	lib/rubocop/cop/performance/reverse_each.rb