Merge pull request rubysherpas#21 from jamescook/issue_20_fix_pgsql_s…

…cope_bug

Fix Topic.by_most_recent_post to be compatible with Postgres

app/models/forem/topic.rb

@@ -15,7 +15,7 @@ class Topic < ActiveRecord::Base
 
     scope :visible, where(:hidden => false)
     scope :by_pinned, order('forem_topics.pinned DESC, forem_topics.id')
-    scope :by_most_recent_post, joins(:posts).order('forem_posts.created_at DESC, forem_topics.id').group('topic_id')
+    scope :by_most_recent_post, joins(:posts).select("DISTINCT forem_posts.topic_id, forem_topics.*").order('forem_posts.created_at DESC, forem_topics.id')
     scope :by_pinned_or_most_recent_post, includes(:posts).
                                           order('forem_topics.pinned DESC').
                                           order('forem_posts.created_at DESC').

spec/models/topic_spec.rb

@@ -45,4 +45,20 @@
       Forem::Topic.by_pinned.first.should == @topic2
     end
   end
+
+  describe ".by_most_recent_post" do
+    before do
+      Forem::Topic.delete_all
+      @topic1 = Factory(:topic)
+      Factory(:post, :topic => @topic, :created_at => 1.seconds.ago)
+      @topic2 = Factory(:topic)
+      Factory(:post, :topic => @topic2, :created_at => 5.seconds.ago)
+      @topic3 = Factory(:topic)
+      Factory(:post, :topic => @topic3, :created_at => 10.seconds.ago)
+    end
+
+    it "should show topics by most recent post" do
+      Forem::Topic.by_most_recent_post.to_a.should == [@topic1, @topic2, @topic3]
+    end
+  end
 end