class Spec::Expectations::NegativeExpectationHandler

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