1 files changed, 9 insertions, 13 deletions
diff --git a/activesupport/lib/active_support/core_ext/module/introspection.rb b/activesupport/lib/active_support/core_ext/module/introspection.rb
index fa692e1b0e..c5bb598bd1 100644
--- a/activesupport/lib/active_support/core_ext/module/introspection.rb
+++ b/activesupport/lib/active_support/core_ext/module/introspection.rb
@@ -1,14 +1,18 @@
-require 'active_support/inflector'
+# frozen_string_literal: true
+
+require "active_support/inflector"
 
 class Module
   # Returns the name of the module containing this one.
   #
   #   M::N.parent_name # => "M"
   def parent_name
-    if defined? @parent_name
+    if defined?(@parent_name)
       @parent_name
     else
-      @parent_name = name =~ /::[^:]+\Z/ ? $`.freeze : nil
+      parent_name = name =~ /::[^:]+\Z/ ? $`.freeze : nil
+      @parent_name = parent_name unless frozen?
+      parent_name
     end
   end
 
@@ -46,21 +50,13 @@ class Module
   def parents
     parents = []
     if parent_name
-      parts = parent_name.split('::')
+      parts = parent_name.split("::")
       until parts.empty?
-        parents << ActiveSupport::Inflector.constantize(parts * '::')
+        parents << ActiveSupport::Inflector.constantize(parts * "::")
         parts.pop
       end
     end
     parents << Object unless parents.include? Object
     parents
   end
-
-  def local_constants #:nodoc:
-    ActiveSupport::Deprecation.warn(<<-MSG.squish)
-      Module#local_constants is deprecated and will be removed in Rails 5.1.
-      Use Module#constants(false) instead.
-    MSG
-    constants(false)
-  end
 end