don't show extra tag info if there is no extra info

lib/philomena_web/templates/tag/_tag_info_row.html.slime

@@ -25,6 +25,7 @@
       = Enum.map_join(@tag.implied_tags, ", ", & &1.name)
       br
 
+    = if present?(@tag.public_links) or present?(@tag.implied_by_tags) or present?(@tag.description) do
       br
       = link "Toggle detailed information", to: "#", data: [click_toggle: ".tag-info__more"]
 

lib/philomena_web/views/app_view.ex

@@ -126,4 +126,13 @@ defmodule PhilomenaWeb.AppView do
   def link_to_fingerprint(fp) do
     link(String.slice(text_or_na(fp), 0..6), to: "#")
   end
+
+  def blank?(nil), do: true
+  def blank?(""), do: true
+  def blank?([]), do: true
+  def blank?(map) when is_map(map), do: map == %{}
+  def blank?(str) when is_binary(str), do: String.trim(str) == ""
+  def blank?(_object), do: false
+
+  def present?(object), do: not blank?(object)
 end

lib/philomena_web/views/duplicate_report_view.ex

@@ -123,13 +123,6 @@ defmodule PhilomenaWeb.DuplicateReportView do
     |> Enum.any?()
   end
 
-  defp blank?(nil), do: true
-  defp blank?(""), do: true
-  defp blank?(str) when is_binary(str), do: String.trim(str) == ""
-  defp blank?(_object), do: false
-
-  defp present?(object), do: not blank?(object)
-
   defp proper_subset?(set1, set2),
     do: MapSet.subset?(set1, set2) and not MapSet.equal?(set1, set2)
 end