# File lib/rspec/core/formatters/documentation_formatter.rb, line 12
        def example_group_started(example_group)
          super(example_group)

          example_group_chain.each_with_index do |nested_example_group, i|
            unless nested_example_group == @previous_nested_example_groups[i]
              output.puts if i == 0
              output.puts "#{'  ' * i}#{nested_example_group.description}"
            end
          end

          @previous_nested_example_groups = example_group_chain
        end