use the last should[not]

lib/spec/matchers/operator_matcher.rb

@@ -21,7 +21,7 @@ def initialize(actual)
       def self.use_custom_matcher_or_delegate(operator)
         define_method(operator) do |expected|
           if matcher = OperatorMatcher.get(@actual.class, operator)
-            return @actual.send(matcher_method, matcher.new(expected))
+            return @actual.send(::Spec::Matchers.last_should, matcher.new(expected))
           else
             ::Spec::Matchers.last_matcher = self
             @operator, @expected = operator, expected
@@ -45,10 +45,6 @@ def description
     end
 
     class PositiveOperatorMatcher < OperatorMatcher #:nodoc:
-      def matcher_method
-        :should
-      end
-
       def __delegate_operator(actual, operator, expected)
         return true if actual.__send__(operator, expected)
         if ['==','===', '=~'].include?(operator)
@@ -61,10 +57,6 @@ def __delegate_operator(actual, operator, expected)
     end
 
     class NegativeOperatorMatcher < OperatorMatcher #:nodoc:
-      def matcher_method
-        :should_not
-      end
-
       def __delegate_operator(actual, operator, expected)
         return true unless actual.__send__(operator, expected)
         return fail_with_message("expected not: #{operator} #{expected.inspect},\n         got: #{operator.gsub(/./, ' ')} #{actual.inspect}")