1 files changed, 13 insertions, 2 deletions
diff --git a/activesupport/lib/active_support/dependencies.rb b/activesupport/lib/active_support/dependencies.rb
index 32cb3a53f4..923d6ad228 100644
--- a/activesupport/lib/active_support/dependencies.rb
+++ b/activesupport/lib/active_support/dependencies.rb
@@ -20,6 +20,9 @@ module ActiveSupport #:nodoc:
   module Dependencies #:nodoc:
     extend self
 
+    UNBOUND_METHOD_MODULE_NAME = Module.instance_method(:name)
+    private_constant :UNBOUND_METHOD_MODULE_NAME
+
     mattr_accessor :interlock, default: Interlock.new
 
     # :doc:
@@ -658,7 +661,7 @@ module ActiveSupport #:nodoc:
 
     # Determine if the given constant has been automatically loaded.
     def autoloaded?(desc)
-      return false if desc.is_a?(Module) && desc.anonymous?
+      return false if desc.is_a?(Module) && real_mod_name(desc).nil?
       name = to_constant_name desc
       return false unless qualified_const_defined?(name)
       autoloaded_constants.include?(name)
@@ -714,7 +717,7 @@ module ActiveSupport #:nodoc:
       when String then desc.sub(/^::/, "")
       when Symbol then desc.to_s
       when Module
-        desc.name ||
+        real_mod_name(desc) ||
           raise(ArgumentError, "Anonymous modules have no name to be referenced by")
       else raise TypeError, "Not a valid constant descriptor: #{desc.inspect}"
       end
@@ -788,6 +791,14 @@ module ActiveSupport #:nodoc:
     def log(message)
       logger.debug("autoloading: #{message}") if logger && verbose
     end
+
+    private
+
+      # Returns the original name of a class or module even if `name` has been
+      # overridden.
+      def real_mod_name(mod)
+        UNBOUND_METHOD_MODULE_NAME.bind(mod).call
+      end
   end
 end