1 files changed, 1 insertions, 8 deletions
diff --git a/activerecord/lib/active_record/readonly_attributes.rb b/activerecord/lib/active_record/readonly_attributes.rb
index 8499bb16e7..ce78f1756d 100644
--- a/activerecord/lib/active_record/readonly_attributes.rb
+++ b/activerecord/lib/active_record/readonly_attributes.rb
@@ -1,4 +1,3 @@
-
 module ActiveRecord
   module ReadonlyAttributes
     extend ActiveSupport::Concern
@@ -12,7 +11,7 @@ module ActiveRecord
       # Attributes listed as readonly will be used to create a new record but update operations will
       # ignore these fields.
       def attr_readonly(*attributes)
-        self._attr_readonly = Set.new(attributes.map { |a| a.to_s }) + (self._attr_readonly || [])
+        self._attr_readonly = Set.new(attributes.map(&:to_s)) + (self._attr_readonly || [])
       end
 
       # Returns an array of all the attributes that have been specified as readonly.
@@ -20,11 +19,5 @@ module ActiveRecord
         self._attr_readonly
       end
     end
-
-    def _attr_readonly
-      message = "Instance level _attr_readonly method is deprecated, please use class level method."
-      ActiveSupport::Deprecation.warn message
-      defined?(@_attr_readonly) ? @_attr_readonly : self.class._attr_readonly
-    end
   end
 end