nevir/rubocop-rspec

# frozen_string_literal: true

module RuboCop
  module Cop
    module RSpec
      # Checks for before/around/after hooks that come after an example.
      #
      # @example
      #   # bad
      #   it 'checks what foo does' do
      #     expect(foo).to be
      #   end
      #
      #   before { prepare }
      #   after { clean_up }
      #
      #   # good
      #   before { prepare }
      #   after { clean_up }
      #
      #   it 'checks what foo does' do
      #     expect(foo).to be
      #   end
      #
      class HooksBeforeExamples < Base
        extend AutoCorrector

        MSG = 'Move `%<hook>s` above the examples in the group.'

        def on_block(node)
          return unless example_group_with_body?(node)

          check_hooks(node.body) if multiline_block?(node.body)
        end

        alias on_numblock on_block

        private

        # @!method example_or_group?(node)
        def_node_matcher :example_or_group?, <<~PATTERN
          {
            ({block numblock} {
              (send #rspec? #ExampleGroups.all ...)
              (send nil? #Examples.all ...)
            } ...)
            (send nil? #Includes.examples ...)
          }
        PATTERN

        def multiline_block?(block)
          block.begin_type?
        end

        def check_hooks(node)
          first_example = find_first_example(node)
          return unless first_example

          first_example.right_siblings.each do |sibling|
            next unless hook?(sibling)

            msg = format(MSG, hook: sibling.method_name)
            add_offense(sibling, message: msg) do |corrector|
              autocorrect(corrector, sibling, first_example)
            end
          end
        end

        def find_first_example(node)
          node.children.find { |sibling| example_or_group?(sibling) }
        end

        def autocorrect(corrector, node, first_example)
          RuboCop::RSpec::Corrector::MoveNode.new(
            node, corrector, processed_source
          ).move_before(first_example)
        end
      end
    end
  end
end