REFACTOR: Add basic tests for `TopicTrackingState#publish_*`.

* Ensure we don't publish events for PMs.

app/models/topic.rb

@@ -99,7 +99,7 @@ class Topic < ActiveRecord::Base
             if: Proc.new { |t|
               (t.new_record? || t.category_id_changed?) &&
               !SiteSetting.allow_uncategorized_topics &&
-              (t.archetype.nil? || t.archetype == Archetype.default) &&
+              (t.archetype.nil? || t.regular?) &&
               (!t.user_id || !t.user.staff?)
             }
 
@@ -273,7 +273,7 @@ class Topic < ActiveRecord::Base
   end
 
   def ensure_topic_has_a_category
-    if category_id.nil? && (archetype.nil? || archetype == Archetype.default)
+    if category_id.nil? && (archetype.nil? || self.regular?)
       self.category_id = SiteSetting.uncategorized_category_id
     end
   end
@@ -463,6 +463,10 @@ class Topic < ActiveRecord::Base
     archetype == Archetype.private_message
   end
 
+  def regular?
+    self.archetype == Archetype.default
+  end
+
   MAX_SIMILAR_BODY_LENGTH ||= 200
 
   def self.similar_to(title, raw, user = nil)

app/models/topic_tracking_state.rb

@@ -10,6 +10,8 @@ class TopicTrackingState
   include ActiveModel::SerializerSupport
 
   CHANNEL = "/user-tracking"
+  UNREAD_MESSAGE_TYPE = "unread".freeze
+  LATEST_MESSAGE_TYPE = "latest".freeze
 
   attr_accessor :user_id,
                 :topic_id,
@@ -20,6 +22,7 @@ class TopicTrackingState
                 :notification_level
 
   def self.publish_new(topic)
+    return unless topic.regular?
 
     message = {
       topic_id: topic.id,
@@ -41,11 +44,11 @@ class TopicTrackingState
   end
 
   def self.publish_latest(topic, staff_only = false)
-    return unless topic.archetype == "regular"
+    return unless topic.regular?
 
     message = {
       topic_id: topic.id,
-      message_type: "latest",
+      message_type: LATEST_MESSAGE_TYPE,
       payload: {
         bumped_at: topic.bumped_at,
         topic_id: topic.id,
@@ -63,7 +66,12 @@ class TopicTrackingState
     MessageBus.publish("/latest", message.as_json, group_ids: group_ids)
   end
 
+  def self.unread_channel_key(user_id)
+    "/unread/#{user_id}"
+  end
+
   def self.publish_unread(post)
+    return unless post.topic.regular?
     # TODO at high scale we are going to have to defer this,
     #   perhaps cut down to users that are around in the last 7 days as well
 
@@ -81,7 +89,7 @@ class TopicTrackingState
 
       message = {
         topic_id: post.topic_id,
-        message_type: "unread",
+        message_type: UNREAD_MESSAGE_TYPE,
         payload: {
           last_read_post_number: tu.last_read_post_number,
           highest_post_number: post.post_number,
@@ -93,7 +101,7 @@ class TopicTrackingState
         }
       }
 
-      MessageBus.publish("/unread/#{tu.user_id}", message.as_json, group_ids: group_ids)
+      MessageBus.publish(self.unread_channel_key(tu.user_id), message.as_json, group_ids: group_ids)
     end
 
   end
@@ -128,7 +136,6 @@ class TopicTrackingState
   end
 
   def self.publish_read(topic_id, last_read_post_number, user_id, notification_level = nil)
-
     highest_post_number = Topic.where(id: topic_id).pluck(:highest_post_number).first
 
     message = {
@@ -142,8 +149,7 @@ class TopicTrackingState
       }
     }
 
-    MessageBus.publish("/unread/#{user_id}", message.as_json, user_ids: [user_id])
+    MessageBus.publish(self.unread_channel_key(user_id), message.as_json, user_ids: [user_id])
-
   end
 
   def self.treat_as_new_topic_clause

spec/models/topic_tracking_state_spec.rb

@@ -10,9 +10,67 @@ describe TopicTrackingState do
     create_post
   end
 
-  it "can correctly publish unread" do
+  let(:topic) { post.topic }
-    # TODO setup stuff and look at messages
+
-    TopicTrackingState.publish_unread(post)
+  describe '#publish_latest' do
+    it 'can correctly publish latest' do
+      message = MessageBus.track_publish("/latest") do
+        described_class.publish_latest(topic)
+      end.first
+
+      data = message.data
+
+      expect(data["topic_id"]).to eq(topic.id)
+      expect(data["message_type"]).to eq(described_class::LATEST_MESSAGE_TYPE)
+      expect(data["payload"]["archetype"]).to eq(Archetype.default)
+    end
+
+    describe 'private message' do
+      let(:topic) { Fabricate(:private_message_topic) }
+
+      it 'should not publish any message' do
+        messages = MessageBus.track_publish do
+          described_class.publish_latest(topic)
+        end
+
+        expect(messages).to eq([])
+      end
+    end
+  end
+
+  describe '#publish_unread' do
+    it "can correctly publish unread" do
+      message = MessageBus.track_publish(described_class.unread_channel_key(post.user.id)) do
+        TopicTrackingState.publish_unread(post)
+      end.first
+
+      data = message.data
+
+      expect(data["topic_id"]).to eq(topic.id)
+      expect(data["message_type"]).to eq(described_class::UNREAD_MESSAGE_TYPE)
+      expect(data["payload"]["archetype"]).to eq(Archetype.default)
+    end
+
+    describe 'for a private message' do
+      let(:private_message_post) { Fabricate(:private_message_post) }
+      let(:topic) { private_message_post.topic }
+
+      before do
+        TopicUser.change(
+          topic.allowed_users.first.id,
+          topic.id,
+          notification_level: TopicUser.notification_levels[:tracking]
+        )
+      end
+
+      it 'should not publish any message' do
+        messages = MessageBus.track_publish do
+          TopicTrackingState.publish_unread(private_message_post)
+        end
+
+        expect(messages).to eq([])
+      end
+    end
   end
 
   it "correctly handles muted categories" do