Fix filtered parameter logging with nil parameter values. Closes #8422.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@6802 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

actionpack/CHANGELOG

@@ -1,5 +1,7 @@
 *SVN*
 
+* Fix filtered parameter logging with nil parameter values.  #8422 [choonkeat]
+
 * Integration tests: alias xhr to xml_http_request and add a request_method argument instead of always using POST.  #7124 [Nik Wakelin, Francois Beausoleil, Wizard]
 
 * Document caches_action.  #5419 [Jarkko Laine]

actionpack/lib/action_controller/base.rb

@@ -441,7 +441,8 @@ def filter_parameter_logging(*filter_words, &block)
             elsif value.is_a?(Hash)
               filtered_parameters[key] = filter_parameters(value)
             elsif block_given?
-              key, value = key.dup, value.dup
+              key = key.dup
+              value = value.dup if value
               yield key, value
               filtered_parameters[key] = value
             else

actionpack/test/controller/filter_params_test.rb

@@ -16,6 +16,7 @@ def test_filter_parameters
     assert @controller.respond_to?(:filter_parameters)
     
     test_hashes = [[{},{},[]],
+    [{'foo'=>nil},{'foo'=>nil},[]],
     [{'foo'=>'bar'},{'foo'=>'bar'},[]],
     [{'foo'=>'bar'},{'foo'=>'bar'},%w'food'],
     [{'foo'=>'bar'},{'foo'=>'[FILTERED]'},%w'foo'],