Refactor Community model.

app/models/community.rb

@@ -4,8 +4,8 @@ class Community < ActiveRecord::Base
   has_many :topics
 
   def participants
-    users_participants = users_who_commented_by +
-                         users_who_topics_author_by +
+    users_participants = users_who_commented +
+                         users_who_topics_author +
                          author_from_community
     users_participants.uniq
   end
@@ -16,24 +16,19 @@ class Community < ActiveRecord::Base
 
   private
 
-  def users_who_commented_by
+  def users_who_commented
     topics_ids = topics.pluck(:id)
     query = "comments.commentable_id IN (?)and comments.commentable_type = 'Topic'"
     User.by_comments(query, topics_ids)
   end
 
-  def users_who_topics_author_by
+  def users_who_topics_author
     author_ids = topics.pluck(:author_id)
     User.by_authors(author_ids)
   end
 
   def author_from_community
-    if from_proposal?
-      User.where(id: proposal.author_id)
-    else
-      investment = Budget::Investment.where(community_id: id).first
-      User.where(id: investment.author_id)
-    end
+    from_proposal? ? User.where(id: proposal.author_id) : User.where(id: investment.author_id)
   end
 
 end