Ruby 1.9 compat: instance_methods are symbols instead of strings. Use…

… the quicker instance_method(sym) rescue false check.

activesupport/lib/active_support/test_case.rb

@@ -9,13 +9,14 @@ class Test::Unit::TestCase #:nodoc:
 
 module ActiveSupport
   class TestCase < Test::Unit::TestCase
-    # test "verify something" do                                   
+    # test "verify something" do
     #   ...
-    # end                                                     
+    # end
     def self.test(name, &block)
-      test_name = "test_#{name.gsub(/[\s]/,'_')}".to_sym
-      raise "#{test_name} is already defined in #{self}" if self.instance_methods.include?(test_name.to_s)
+      test_name = "test_#{name.gsub(/\s+/,'_')}".to_sym
+      defined = instance_method(test_name) rescue false
+      raise "#{test_name} is already defined in #{self}" if defined
       define_method(test_name, &block)
     end
   end
-end
+end