Rename rw to expected_rw in RdocAttrTest add_alias test

Author: extern-c

test/rdoc/code_object/attr_test.rb

@@ -190,15 +190,15 @@ def test_type
   [
     ['bar', 'baz', 'R'],
     ['bar=', 'baz=', 'W']
-  ].each do |original_name, new_name, rw|
+  ].each do |original_name, new_name, expected_rw|
     define_method("test_add_alias_#{new_name}_for_an_attribute_accessor") do
       context = RDoc::Context.new
       attr = RDoc::Attr.new nil, original_name, 'RW', ''
       an_alias = RDoc::Alias.new nil, original_name, new_name, ''
 
       new_attr = attr.add_alias an_alias, context
 
-      assert_equal rw, new_attr.rw
+      assert_equal expected_rw, new_attr.rw
     end
   end
 end