    # File lib/action_view/helpers/asset_tag_helper.rb, line 185
          def image_tag(source, options = {})
            options.symbolize_keys!

            options[:src] = image_path(source)
            options[:alt] ||= File.basename(options[:src], '.*').split('.').first.capitalize

            if options[:size]
              options[:width], options[:height] = options[:size].split("x") if options[:size] =~ %r{^\d+x\d+$}
              options.delete(:size)
            end

            tag("img", options)
          end