deprecates Module#local_constant_names

activesupport/CHANGELOG.md

 ## Rails 4.0.0 (unreleased) ##
 
+*    Deprecates the compatibility method Module#local_constant_names,
+     use Module#local_constants instead (which returns symbols). *fxn*
+
 *    Deletes the compatibility method Module#method_names,
      use Module#methods from now on (which returns symbols). *fxn*
 

activesupport/lib/active_support/core_ext/module/introspection.rb

@@ -61,9 +61,19 @@ def local_constants #:nodoc:
     constants(false)
   end
 
-  # Returns the names of the constants defined locally rather than the
-  # constants themselves. See <tt>local_constants</tt>.
+  # *DEPRECATED*: Use +local_constants+ instead.
+  #
+  # Returns the names of the constants defined locally as strings.
+  #
+  #   module M
+  #     X = 1
+  #   end
+  #   M.local_constant_names # => ["X"]
+  #
+  # This method is useful for forward compatibility, since Ruby 1.8 returns
+  # constant names as strings, whereas 1.9 returns them as symbols.
   def local_constant_names
+    ActiveSupport::Deprecation.warn('Module#local_constant_names is deprecated, use Module#local_constants instead', caller)
     local_constants.map { |c| c.to_s }
   end
 end

activesupport/lib/active_support/dependencies.rb

@@ -105,7 +105,7 @@ def new_constants
           next unless mod.is_a?(Module)
 
           # Get a list of the constants that were added
-          new_constants = mod.local_constant_names - original_constants
+          new_constants = mod.local_constants - original_constants
 
           # self[namespace] returns an Array of the constants that are being evaluated
           # for that namespace. For instance, if parent.rb requires child.rb, the first
@@ -133,7 +133,7 @@ def watch_namespaces(namespaces)
         namespaces.map do |namespace|
           module_name = Dependencies.to_constant_name(namespace)
           original_constants = Dependencies.qualified_const_defined?(module_name) ?
-            Inflector.constantize(module_name).local_constant_names : []
+            Inflector.constantize(module_name).local_constants : []
 
           watching << module_name
           @stack[module_name] << original_constants

activesupport/test/core_ext/module_test.rb

@@ -212,6 +212,12 @@ def test_parents
   def test_local_constants
     assert_equal %w(Constant1 Constant3), Ab.local_constants.sort.map(&:to_s)
   end
+
+  def test_local_constant_names
+    ActiveSupport::Deprecation.silence do
+      assert_equal %w(Constant1 Constant3), Ab.local_constant_names
+    end
+  end
 end
 
 module BarMethodAliaser

railties/guides/source/active_support_core_extensions.textile

@@ -692,7 +692,8 @@ NOTE: Defined in +active_support/core_ext/module/introspection.rb+.
 
 h4. Constants
 
-The method +local_constants+ returns the names of the constants that have been defined in the receiver module:
+The method +local_constants+ returns the names of the constants that have been
+defined in the receiver module:
 
 <ruby>
 module X
@@ -708,7 +709,8 @@ X.local_constants    # => [:X1, :X2, :Y]
 X::Y.local_constants # => [:Y1, :X1]
 </ruby>
 
-The names are returned as symbols. The method +local_constant_names+ always returns strings.
+The names are returned as symbols. (The method +local_constant_names+ returns
+strings, but +local_constant_names+ is deprecated.)
 
 NOTE: Defined in +active_support/core_ext/module/introspection.rb+.