guard_against_redefining_existing_example_group

# File lib/spec/example/shared_example_group.rb, line 24
        def guard_against_redefining_existing_example_group(new_example_group)
          existing_example_group = find_shared_example_group(new_example_group.description)
          return unless existing_example_group
          return if new_example_group.equal?(existing_example_group)
          return if spec_path(new_example_group) == spec_path(existing_example_group)
          raise ArgumentError.new("Shared Example '#{existing_example_group.description}' already exists")
        end