allow more forum posts to be voted on (fixes #3677)

app/models/forum_post.rb

@@ -6,6 +6,8 @@ class ForumPost < ApplicationRecord
   belongs_to_updater
   belongs_to :topic, :class_name => "ForumTopic"
   has_many :votes, class_name: "ForumPostVote"
+  has_one :tag_relationship
+  has_one :bulk_update_request
   before_validation :initialize_is_deleted, :on => :create
   after_create :update_topic_updated_at_on_create
   after_update :update_topic_updated_at_on_update_for_original_posts
@@ -129,6 +131,11 @@ class ForumPost < ApplicationRecord
     end
   end
 
+  def votable?
+    # shortcut to eliminate posts that are probably not tag change requests
+    body.match(/->/) && (bulk_update_request.present? || tag_relationship.present?) && created_at >= TagRelationship::EXPIRY.days.ago
+  end
+
   def voted?(user, score)
     votes.where(creator_id: user.id, score: score).exists?
   end

app/views/forum_posts/_forum_post.html.erb

@@ -44,7 +44,7 @@
         <% else %>
           <li><%= link_to "Permalink", forum_post_path(forum_post) %></li>
         <% end %>
-        <% if forum_post.is_original_post?(original_forum_post_id) %>
+        <% if forum_post.votable? %>
           <ul class="votes" id="forum-post-votes-for-<%= forum_post.id %>">
             <%= render "forum_post_votes/list", votes: forum_post.votes, forum_post: forum_post %>
           </ul>

test/unit/forum_post_test.rb

@@ -14,6 +14,17 @@ class ForumPostTest < ActiveSupport::TestCase
       CurrentUser.ip_addr = nil
     end
 
+    context "#votable?" do
+      setup do
+        @post = FactoryBot.build(:forum_post, :topic_id => @topic.id, :body => "[[aaa]] -> [[bbb]]")
+        @tag_alias = FactoryBot.create(:tag_alias, forum_post: @post)
+      end
+
+      should "be true for a post associated with a tag alias" do
+        assert(@post.votable?)
+      end
+    end
+
     context "that mentions a user" do
       context "in a quote block" do
         setup do