Include assignments in thread

app/helpers/comments_helper.rb

@@ -1,6 +1,11 @@
 module CommentsHelper
   def render_comments_and_boosts(bubble)
-    combined_collection = (bubble.comments + bubble.boosts).sort_by(&:updated_at)
+    combined_collection = (
+      bubble.comments +
+      bubble.boosts +
+      bubble.assignments
+    ).sort_by(&:created_at)
+
     safe_join([
       render_creator_summary(bubble, combined_collection),
       render_remaining_items(combined_collection)
@@ -8,10 +13,27 @@ module CommentsHelper
   end
 
   private
+    def render_comments_and_boosts(bubble)
+      combined_collection = (
+        bubble.comments +
+        bubble.boosts +
+        bubble.assignments
+      ).sort_by(&:created_at)
+
+      safe_join([
+        render_creator_summary(bubble, combined_collection),
+        render_remaining_items(combined_collection)
+      ])
+    end
+
     def render_creator_summary(bubble, combined_collection)
       content_tag(:div, class: "comment--upvotes flex-inline align-start gap fill-white border-radius center position-relative") do
         summary = "Added by #{bubble.creator.name} #{time_ago_in_words(bubble.created_at)} ago"
-        summary += render_initial_boosts(combined_collection) if combined_collection.first.is_a?(Boost)
+
+        initial_assignment = combined_collection.find { |item| item.is_a?(Assignment) }
+        summary += ", assigned to #{initial_assignment.user.name}" if initial_assignment
+
+        summary += render_initial_boosts(combined_collection)
         summary.html_safe
       end
     end
@@ -33,25 +55,53 @@ module CommentsHelper
     end
 
     def render_remaining_items(combined_collection)
-      grouped_boosts = []
-      safe_join(combined_collection.drop(initial_boosts_count(combined_collection)).map do |item|
-        if item.is_a?(Boost)
-          grouped_boosts << item
-          next if combined_collection[combined_collection.index(item) + 1].is_a?(Boost)
-          render_grouped_boosts(grouped_boosts.dup).tap { grouped_boosts.clear }
-        else
+      grouped_items = []
+      safe_join(combined_collection.drop(initial_items_count(combined_collection)).map do |item|
+        case item
+        when Boost, Assignment
+          grouped_items << item
+          next if combined_collection[combined_collection.index(item) + 1].is_a?(Boost) || combined_collection[combined_collection.index(item) + 1].is_a?(Assignment)
+          render_grouped_items(grouped_items.dup).tap { grouped_items.clear }
+        when Comment
           render partial: "comments/comment", object: item
         end
       end.compact)
     end
 
+    def render_grouped_items(items)
+      return if items.empty?
+
+      boosts = items.select { |item| item.is_a?(Boost) }
+      assignments = items.select { |item| item.is_a?(Assignment) }
+
+      content_tag(:div, class: "comment--upvotes flex-inline align-start gap fill-white border-radius center position-relative") do
+        safe_join([
+          render_grouped_boosts(boosts),
+          render_grouped_assignments(assignments)
+        ].compact)
+      end
+    end
+
     def render_grouped_boosts(boosts)
       return if boosts.empty?
       user_boosts = boosts.group_by(&:creator).transform_values(&:count)
       boost_summaries = user_boosts.map { |user, count| "#{user.name} +#{count}" }
-      content_tag(:div, class: "comment--upvotes flex-inline align-start gap fill-white border-radius center position-relative") do
-        boost_summaries.to_sentence.html_safe
+      content_tag(:div, boost_summaries.to_sentence.html_safe)
+    end
+
+    def render_grouped_assignments(assignments)
+      return if assignments.empty?
+      assignment_summaries = assignments.map { |assignment| "Assigned to #{assignment.user.name} #{time_ago_in_words(assignment.created_at)} ago" }
+      content_tag(:div, assignment_summaries.join(", ").html_safe)
+    end
+
+    def initial_items_count(combined_collection)
+      count = 0
+      combined_collection.each do |item|
+        break if item.is_a?(Comment)
+        count += 1
       end
+      count
     end
 
     def initial_boosts_count(combined_collection)