expanded_cache_key

# File actionview/lib/action_view/renderer/partial_renderer/collection_caching.rb, line 42
      def expanded_cache_key(key)
        key = @view.combined_fragment_cache_key(@view.cache_fragment_name(key, virtual_path: @template.virtual_path))
        key.frozen? ? key.dup : key # #read_multi & #write may require mutability, Dalli 2.6.0.
      end