Use finder to decide to show note to user

Given the note is about how to interpret ancestor clusters, use the
finder which actually knows if there are any ancestor clusters to find
out if the note should be shown, rather than passing the same info via a
view to a helper

Added note about Kaminari.paginate_array

Link to followup issue too

1 files changed, 10 insertions, 1 deletions

diff --git a/app/finders/cluster_ancestors_finder.rb b/app/finders/cluster_ancestors_finder.rb
index 586fceb258a..2f9709ee057 100644
--- a/app/finders/cluster_ancestors_finder.rb
+++ b/app/finders/cluster_ancestors_finder.rb
@@ -1,6 +1,8 @@
 # frozen_string_literal: true
 
 class ClusterAncestorsFinder
+  include Gitlab::Utils::StrongMemoize
+
   def initialize(clusterable, current_user)
     @clusterable = clusterable
     @current_user = current_user
@@ -12,6 +14,10 @@ class ClusterAncestorsFinder
     clusterable.clusters + ancestor_clusters
   end
 
+  def has_ancestor_clusters?
+    ancestor_clusters.any?
+  end
+
   private
 
   attr_reader :clusterable, :current_user
@@ -20,7 +26,10 @@ class ClusterAncestorsFinder
     Ability.allowed?(current_user, :read_cluster, clusterable)
   end
 
+  # This unfortunately returns an Array, not a Relation!
   def ancestor_clusters
-    Clusters::Cluster.ancestor_clusters_for_clusterable(clusterable)
+    strong_memoize(:ancestor_clusters) do
+      Clusters::Cluster.ancestor_clusters_for_clusterable(clusterable)
+    end
   end
 end