Merge pull request #325: Render the boosts a message has preloaded instead of querying them again

Reviewed and merged by GPT on behalf of DHH.

app/views/messages/boosts/_boosts.html.erb

@@ -2,7 +2,7 @@
   <div class="boosts flex flex-wrap align-center gap full-width" style="--column-gap: 0.4ch; --row-gap: 0"
       data-controller="turbo-streaming" data-action="turbo:submit-start->turbo-streaming#unsubscribe">
     <div class="flex-inline flex-wrap gap" id="<%= dom_id(message, :boosts) %>" data-turbo-streaming-target="container">
-      <%= render partial: "messages/boosts/boost", collection: message.boosts.ordered.includes(:booster) %>
+      <%= render partial: "messages/boosts/boost", collection: message.boosts.loaded? ? message.boosts.sort_by(&:created_at) : message.boosts.ordered.includes(:booster) %>
     </div>
 
     <%= turbo_frame_tag message, :new_boost do %>

test/controllers/messages_caching_test.rb

@@ -53,6 +53,20 @@ class MessagesCachingTest < ActionDispatch::IntegrationTest
     end
   end
 
+  test "messages render their preloaded boosts in order without querying them again" do
+    earlier = messages(:fourth).boosts.create! booster: users(:jason), content: "🥇", created_at: 1.day.ago
+    in_order = [ dom_id(earlier), dom_id(boosts(:fourth_by_bender)) ]
+
+    assert_no_queries_match(/ORDER BY "boosts"/) do
+      get room_messages_url(rooms(:watercooler))
+    end
+    assert_response :success
+    assert_equal in_order, css_select("##{dom_id(messages(:fourth), :boosts)} .boost").map { it["id"] }
+
+    get message_boosts_url(messages(:fourth))
+    assert_equal in_order, css_select("##{dom_id(messages(:fourth), :boosts)} .boost").map { it["id"] }
+  end
+
   private
     def with_memory_cache
       old_cache = Rails.cache