def liked_by
      # subquery = Activity.where(activity_object_id: id)
      # people   = Person.joins(activity_object: { actor_activities: :verb })
      #                  .merge(subquery)
      # likers   = people.merge(Verb.by_display_name("like"))
      # unlikers = people.merge(Verb.by_display_name("unlike")).pluck(:id)

      query    = Activity.joins(:verb).with_activity_object_id(id: id)
      likers   = query.merge(Verb.with_display_name(name: "like"))
      unlikers = query.merge(Verb.with_display_name(name: "unlike"))
      people   = likers.map(&:actor)

      unlikers.each do |activity|
        people.delete_at people.index(activity.actor)
      end

      people
    end
def liked_by
      # subquery = Activity.where(activity_object_id: id)
      # people   = Person.joins(activity_object: { actor_activities: :verb })
      #                  .merge(subquery)
      # likers   = people.merge(Verb.by_display_name("like"))
      # unlikers = people.merge(Verb.by_display_name("unlike")).pluck(:id)

      query    = Activity.joins(:verb).with_activity_object_id(id: id)
      likers   = query.merge(Verb.with_display_name(name: "like"))
      unlikers = query.merge(Verb.with_display_name(name: "unlike"))
      people   = likers.map(&:actor)

      unlikers.each do |activity|
        people.delete_at people.index(activity.actor)
      end

      people
    end
Instance Methods
 A list of people that like this activity object

 @return [Array]
 REFACTOR: DRY this up. Reduce database calls