You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: block_snippet_extractor.rb
    path of file: ./repos/rspec-expectations/lib/rspec/expectations
    
    the code of the file until where you have to start completion: module RSpec
  module Expectations
    # @private
    class BlockSnippetExtractor # rubocop:disable Metrics/ClassLength
      # rubocop should properly handle `Struct.new {}` as an inner class definition.

      attr_reader :proc, :method_name

      def self.try_extracting_single_line_body_of(proc, method_name)
        lines = new(proc, method_name).body_content_lines
        return nil unless lines.count == 1
        lines.first
      rescue Error
        nil
      end

      def initialize(proc, method_name)
        @proc = proc
        @method_name = method_name.to_s.freeze
      end

      # Ideally we should properly handle indentations of mu
    
        def candidate_block_wrapper_nodes
          @candidate_block_wrapper_nodes ||= candidate_method_ident_nodes.map do |method_ident_node|
            block_wrapper_node = method_ident_node.each_ancestor.find { |node| node.type == :method_add_block }
            next nil unless block_wrapper_node
            method_call_node = block_wrapper_node.children.first
            method_call_node.include?(method_ident_node) ? block_wrapper_node : nil
          end.compact
        end

        def candidate_method_ident_nodes
          source.nodes_by_line_number[beginning_line_number].select do |node|
            method_ident_node?(node)
          end
        end

        def method_ident_node?(node)
          node.type == :@ident && node.args.first == method_name
        end
      end