fixes #2731: Expunged posts should clear favorite groups

app/models/favorite_group.rb

@@ -18,6 +18,11 @@ class FavoriteGroup < ActiveRecord::Base
       where("favorite_groups.creator_id = ?", user_id)
     end
 
+    def for_post(post_id)
+      regexp = "(^#{post_id}$|^#{post_id} | #{post_id}$| #{post_id} )"
+      where("favorite_groups.post_ids ~ ?", regexp)
+    end
+
     def named(name)
       where("lower(name) = ?", name.to_s.mb_chars.downcase.strip)
     end

app/models/post.rb

@@ -959,6 +959,12 @@ class Post < ActiveRecord::Base
         groups.uniq
       end
     end
+
+    def remove_from_fav_groups
+      FavoriteGroup.for_post(id).find_each do |group|
+        group.remove!(self)
+      end
+    end
   end
 
   module UploaderMethods
@@ -1313,6 +1319,7 @@ class Post < ActiveRecord::Base
         update_children_on_destroy
         decrement_tag_post_counts
         remove_from_all_pools
+        remove_from_fav_groups
         destroy
         update_parent_on_destroy
       end

test/factories/favorite_group.rb

@@ -0,0 +1,4 @@
+FactoryGirl.define do
+  factory(:favorite_group) do
+  end
+end

test/unit/favorite_group_test.rb

@@ -0,0 +1,76 @@
+require 'test_helper'
+
+class FavoriteTest < ActiveSupport::TestCase
+  def setup
+    super
+    @user = FactoryGirl.create(:user)
+    CurrentUser.user = @user
+    CurrentUser.ip_addr = "127.0.0.1"
+    @fav_group = FactoryGirl.create(:favorite_group, creator: @user, name: "blah")
+  end
+
+  def teardown
+    super
+    CurrentUser.user = nil
+    CurrentUser.ip_addr = nil
+  end
+
+  context "searching by post id" do
+    context "when the id is the only one" do
+      setup do
+        @fav_group.post_ids = "1"
+        @fav_group.save
+      end
+
+      should "return the fav group" do
+        assert_equal(@fav_group.id, FavoriteGroup.for_post(1).first.try(:id))
+      end
+    end
+
+    context "when the id is in the beginning" do
+      setup do
+        @fav_group.post_ids = "1 2"
+        @fav_group.save
+      end
+
+      should "return the fav group" do
+        assert_equal(@fav_group.id, FavoriteGroup.for_post(1).first.try(:id))
+      end      
+    end
+
+    context "when the id is in the middle" do
+      setup do
+        @fav_group.post_ids = "3 1 2"
+        @fav_group.save
+      end
+
+      should "return the fav group" do
+        assert_equal(@fav_group.id, FavoriteGroup.for_post(1).first.try(:id))
+      end
+    end
+
+    context "when the id is in the end" do
+      setup do
+        @fav_group.post_ids = "2 1"
+        @fav_group.save
+      end
+
+      should "return the fav group" do
+        assert_equal(@fav_group.id, FavoriteGroup.for_post(1).first.try(:id))
+      end  
+    end
+  end
+
+  context "expunging a post" do
+    setup do
+      @post = FactoryGirl.create(:post)
+      @fav_group.add!(@post)
+    end
+
+    should "remove it from all favorite groups" do
+      @post.expunge!
+      @fav_group.reload
+      assert_equal("", @fav_group.post_ids)
+    end
+  end
+end