DEV: Introduced topic_query_create_list_topics modifier (#21016)

Introduced a modifier on topic_query to change list while they're created

Co-authored-by: Jarek Radosz <jradosz@gmail.com>

lib/topic_query.rb

@@ -460,6 +460,8 @@ class TopicQuery
     options[:filter] ||= filter
     topics ||= default_results(options)
     topics = yield(topics) if block_given?
+    topics =
+      DiscoursePluginRegistry.apply_modifier(:topic_query_create_list_topics, topics, options, self)
 
     options = options.merge(@options)
     if %w[activity default].include?(options[:order] || "activity") && !options[:unordered] &&

spec/lib/topic_query_spec.rb

@@ -1940,4 +1940,29 @@ RSpec.describe TopicQuery do
       ).to contain_exactly(category.topic_id, subcategory.topic_id, subcategory_regular_topic.id)
     end
   end
+
+  describe "with topic_query_create_list_topics modifier" do
+    fab!(:topic1) { Fabricate(:topic, created_at: 3.days.ago, bumped_at: 1.hour.ago) }
+    fab!(:topic2) { Fabricate(:topic, created_at: 2.days.ago, bumped_at: 3.hour.ago) }
+
+    after { DiscoursePluginRegistry.clear_modifiers! }
+
+    it "allows changing" do
+      original_topic_query = TopicQuery.new(user)
+
+      Plugin::Instance
+        .new
+        .register_modifier(:topic_query_create_list_topics) do |topics, options, topic_query|
+          expect(topic_query).to eq(topic_query)
+          topic_query.options[:order] = "created"
+          topics
+        end
+
+      expect(original_topic_query.list_latest.topics.map(&:id)).to eq([topic1, topic2].map(&:id))
+
+      DiscoursePluginRegistry.clear_modifiers!
+
+      expect(original_topic_query.list_latest.topics.map(&:id)).to eq([topic2, topic1].map(&:id))
+    end
+  end
 end