diff --git a/activesupport/lib/active_support/testing/declarative.rb b/activesupport/lib/active_support/testing/declarative.rb
index c349bb5fb1..e709e6edf5 100644
--- a/activesupport/lib/active_support/testing/declarative.rb
+++ b/activesupport/lib/active_support/testing/declarative.rb
@@ -34,7 +34,7 @@ module ActiveSupport
         #   end
         def test(name, &block)
           test_name = "test_#{name.gsub(/\s+/,'_')}".to_sym
-          defined = instance_method(test_name) rescue false
+          defined = method_defined? test_name
           raise "#{test_name} is already defined in #{self}" if defined
           if block_given?
             define_method(test_name, &block)