handle_matcher (Spec::Expectations::NegativeExpectationHandler)

    # File lib/spec/expectations/handler.rb, line 27
          def self.handle_matcher(actual, matcher, message=nil, &block)
            ::Spec::Matchers.last_should = :should_not
            ::Spec::Matchers.last_matcher = matcher
            return ::Spec::Matchers::NegativeOperatorMatcher.new(actual) if matcher.nil?

            match = matcher.respond_to?(:does_not_match?) ?
                    !matcher.does_not_match?(actual, &block) :
                    matcher.matches?(actual, &block)
            return match unless match

            message ||= matcher.respond_to?(:failure_message_for_should_not) ?
                        matcher.failure_message_for_should_not :
                        matcher.negative_failure_message

            if matcher.respond_to?(:diffable?) && matcher.diffable?
              ::Spec::Expectations.fail_with message, matcher.expected.first, matcher.actual
            else
              ::Spec::Expectations.fail_with message
            end
          end