1 files changed, 13 insertions, 2 deletions
diff --git a/activerecord/lib/active_record/attribute_methods.rb b/activerecord/lib/active_record/attribute_methods.rb
index 0ca0e5dcdb..83b5a5e698 100644
--- a/activerecord/lib/active_record/attribute_methods.rb
+++ b/activerecord/lib/active_record/attribute_methods.rb
@@ -59,7 +59,7 @@ module ActiveRecord
         # attribute methods.
         generated_attribute_methods.synchronize do
           return false if @attribute_methods_generated
-          superclass.define_attribute_methods unless self == base_class
+          superclass.define_attribute_methods unless base_class?
           super(attribute_names)
           @attribute_methods_generated = true
         end
@@ -175,9 +175,20 @@ module ActiveRecord
       # Regexp whitelist. Matches the following:
       #   "#{table_name}.#{column_name}"
       #   "#{table_name}.#{column_name} #{direction}"
+      #   "#{table_name}.#{column_name} #{direction} NULLS FIRST"
+      #   "#{table_name}.#{column_name} NULLS LAST"
       #   "#{column_name}"
       #   "#{column_name} #{direction}"
-      COLUMN_NAME_ORDER_WHITELIST = /\A(?:\w+\.)?\w+(?:\s+asc|\s+desc)?\z/i
+      #   "#{column_name} #{direction} NULLS FIRST"
+      #   "#{column_name} NULLS LAST"
+      COLUMN_NAME_ORDER_WHITELIST = /
+        \A
+        (?:\w+\.)?
+        \w+
+        (?:\s+asc|\s+desc)?
+        (?:\s+nulls\s+(?:first|last))?
+        \z
+      /ix
 
       def enforce_raw_sql_whitelist(args, whitelist: COLUMN_NAME_WHITELIST) # :nodoc:
         unexpected = args.reject do |arg|