push attribute constant cache in to the attribute methods module

activerecord/lib/active_record/attribute_methods.rb

@@ -26,7 +26,15 @@ def inherited(child_class) #:nodoc:
       end
 
       def initialize_generated_modules # :nodoc:
-        @generated_attribute_methods = Module.new { extend Mutex_m }
+        @generated_attribute_methods = Module.new {
+          extend Mutex_m
+
+          const_set :AttrNames, Module.new {
+            def self.const_missing(name)
+              const_set(name, [name.to_s.sub(/ATTR_/, '')].pack('h*').freeze)
+            end
+          }
+        }
         @attribute_methods_generated = false
         include @generated_attribute_methods
       end

activerecord/lib/active_record/core.rb

@@ -90,12 +90,6 @@ def self.connection_handler=(handler)
     module ClassMethods
       def initialize_generated_modules
         super
-        # force attribute methods to be higher in inheritance hierarchy than other generated methods
-        generated_attribute_methods.const_set(:AttrNames, Module.new {
-          def self.const_missing(name)
-            const_set(name, [name.to_s.sub(/ATTR_/, '')].pack('h*').freeze)
-          end
-        })
 
         generated_feature_methods
       end