1 files changed, 5 insertions, 35 deletions
diff --git a/activerecord/lib/active_record/associations/has_many_through_association.rb b/activerecord/lib/active_record/associations/has_many_through_association.rb
index 0968b0068e..4897ec44e9 100644
--- a/activerecord/lib/active_record/associations/has_many_through_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_through_association.rb
@@ -11,21 +11,6 @@ module ActiveRecord
         @through_association = nil
       end
 
-      # Returns the size of the collection by executing a SELECT COUNT(*) query
-      # if the collection hasn't been loaded, and by calling collection.size if
-      # it has. If the collection will likely have a size greater than zero,
-      # and if fetching the collection will be needed afterwards, one less
-      # SELECT query will be generated by using #length instead.
-      def size
-        if has_cached_counter?
-          owner.read_attribute cached_counter_attribute_name(reflection)
-        elsif loaded?
-          target.size
-        else
-          super
-        end
-      end
-
       def concat(*records)
         unless owner.new_record?
           records.flatten.each do |record|
@@ -62,15 +47,7 @@ module ActiveRecord
         end
 
         save_through_record(record)
-        if has_cached_counter? && !through_reflection_updates_counter_cache?
-          ActiveSupport::Deprecation.warn \
-            "Automatic updating of counter caches on through associations has been " \
-            "deprecated, and will be removed in Rails 5.0. Instead, please set the " \
-            "appropriate counter_cache options on the has_many and belongs_to for " \
-            "your associations to #{through_reflection.name}."
 
-          update_counter_in_database(1)
-        end
         record
       end
 
@@ -158,17 +135,15 @@ module ActiveRecord
             if scope.klass.primary_key
               count = scope.destroy_all.length
             else
-              scope.to_a.each do |record|
-                record.run_callbacks :destroy
-              end
+              scope.each(&:_run_destroy_callbacks)
 
               arel = scope.arel
 
-              stmt = Arel::DeleteManager.new arel.engine
+              stmt = Arel::DeleteManager.new
               stmt.from scope.klass.arel_table
               stmt.wheres = arel.constraints
 
-              count = scope.klass.connection.delete(stmt, 'SQL', scope.bind_values)
+              count = scope.klass.connection.delete(stmt, 'SQL', scope.bound_attributes)
             end
           when :nullify
             count = scope.update_all(source_reflection.foreign_key => nil)
@@ -185,9 +160,9 @@ module ActiveRecord
 
           if through_reflection.collection? && update_through_counter?(method)
             update_counter(-count, through_reflection)
+          else
+            update_counter(-count)
           end
-
-          update_counter(-count)
         end
 
         def through_records_for(record)
@@ -225,11 +200,6 @@ module ActiveRecord
         def invertible_for?(record)
           false
         end
-
-        def through_reflection_updates_counter_cache?
-          counter_name = cached_counter_attribute_name
-          inverse_updates_counter_named?(counter_name, through_reflection)
-        end
     end
   end
 end