FIX: user topic and post counts can become negative when staff deletes posts in personal messages

lib/post_destroyer.rb

@@ -78,21 +78,23 @@ class PostDestroyer
   def staff_recovered
     @post.recover!
 
-    if author = @post.user
-      if @post.is_first_post?
-        author.user_stat.topic_count += 1
-      else
-        author.user_stat.post_count += 1
+    if @post.topic && !@post.topic.private_message?
+      if author = @post.user
+        if @post.is_first_post?
+          author.user_stat.topic_count += 1
+        else
+          author.user_stat.post_count += 1
+        end
+        author.user_stat.save!
       end
-      author.user_stat.save!
-    end
 
-    if @post.is_first_post? && @post.topic && !@post.topic.private_message?
-      # Update stats of all people who replied
-      counts = Post.where(post_type: Post.types[:regular], topic_id: @post.topic_id).where('post_number > 1').group(:user_id).count
-      counts.each do |user_id, count|
-        if user_stat = UserStat.where(user_id: user_id).first
-          user_stat.update_attributes(post_count: user_stat.post_count + count)
+      if @post.is_first_post?
+        # Update stats of all people who replied
+        counts = Post.where(post_type: Post.types[:regular], topic_id: @post.topic_id).where('post_number > 1').group(:user_id).count
+        counts.each do |user_id, count|
+          if user_stat = UserStat.where(user_id: user_id).first
+            user_stat.update_attributes(post_count: user_stat.post_count + count)
+          end
         end
       end
     end
@@ -248,10 +250,12 @@ class PostDestroyer
       author.user_stat.first_post_created_at = author.posts.order('created_at ASC').first.try(:created_at)
     end
 
-    if @post.post_type == Post.types[:regular] && !@post.is_first_post? && !@topic.nil?
-      author.user_stat.post_count -= 1
+    if @post.topic && !@post.topic.private_message?
+      if @post.post_type == Post.types[:regular] && !@post.is_first_post? && !@topic.nil?
+        author.user_stat.post_count -= 1
+      end
+      author.user_stat.topic_count -= 1 if @post.is_first_post?
     end
-    author.user_stat.topic_count -= 1 if @post.is_first_post?
 
     # We don't count replies to your own topics in topic_reply_count
     if @topic && author.id != @topic.user_id

spec/components/post_destroyer_spec.rb

@@ -360,6 +360,32 @@ describe PostDestroyer do
 
   end
 
+  context 'private message' do
+    let(:author) { Fabricate(:user) }
+    let(:private_message) { Fabricate(:private_message_topic, user: author) }
+    let!(:first_post) { Fabricate(:post, topic: private_message, user: author) }
+    let!(:second_post) { Fabricate(:post, topic: private_message, user: author, post_number: 2)}
+
+    it "doesn't update post_count for a reply" do
+      expect {
+        PostDestroyer.new(admin, second_post).destroy
+        author.reload
+      }.to_not change { author.post_count }
+
+      expect {
+        PostDestroyer.new(admin, second_post).recover
+      }.to_not change { author.post_count }
+    end
+
+    it "doesn't update topic_count for first post" do
+      expect {
+        PostDestroyer.new(admin, first_post).destroy
+        author.reload
+      }.to_not change { author.topic_count }
+      expect(author.post_count).to eq(0) # also unchanged
+    end
+  end
+
   context 'deleting the second post in a topic' do
 
     let(:user) { Fabricate(:user) }

spec/models/topic_converter_spec.rb

@@ -56,8 +56,10 @@ describe TopicConverter do
         first_post
         topic_user = TopicUser.create!(user_id: author.id, topic_id: private_message.id, posted: true)
         expect(private_message.user.user_stat.topic_count).to eq(0)
+        expect(private_message.user.user_stat.post_count).to eq(0)
         private_message.convert_to_public_topic(admin)
         expect(private_message.reload.user.user_stat.topic_count).to eq(1)
+        expect(private_message.user.user_stat.post_count).to eq(1)
         expect(topic_user.reload.notification_level).to eq(TopicUser.notification_levels[:watching])
       end