rubocop cleaning

app/models/concerns/rating_average.rb

@@ -2,27 +2,28 @@ module RatingAverage
   extend ActiveSupport::Concern
 
   def average_rating
-    if self.class == Beer
+    if instance_of?(Beer)
       ratings = [self]
-    elsif self.class == Brewery
+    elsif instance_of?(Brewery)
       # creates empty arrays for beers that have no ratings
       # + wraps the array in an array
       ratings = beers.map { |b| b.ratings }.reject(&:blank?)[0]
-    elsif self.class == User
+    elsif instance_of?(User)
       ratings = self.ratings
     else
       raise "Wrong class type for calculating average, #{self.class}"
     end
 
     return 0 unless ratings.count > 0
+
     ratings.map { |r| r.score }.sum / ratings.count.to_f
   end
 
   def count_ratings
-    if self.class == Beer or User
-      return self.ratings.count
-    elsif self.class == Brewery
-      return self.beers.map { |b| b.ratings.count }.sum
+    if instance_of?(Beer) || User
+      ratings.count
+    elsif instance_of?(Brewery)
+      beers.map { |b| b.ratings.count }.sum
     else
       raise "Wrong class type for counting ratings, #{self.class}"
     end

app/models/rating.rb

@@ -3,6 +3,6 @@ class Rating < ApplicationRecord
   belongs_to :user
 
   def to_s
-    "#{self.beer.name}: #{self.score}"
+    "#{beer.name}: #{score}"
   end
 end