29: def handle_matcher(actual, matcher, &block)
30: unless matcher.respond_to?(:matches?)
31: raise InvalidMatcherError, "Expected a matcher, got #{matcher.inspect}."
32: end
33:
34: unless matcher.respond_to?(:negative_failure_message)
35: Spec::Expectations.fail_with(
36: "Matcher does not support should_not.\nSee Spec::Matchers for more information\nabout matchers.\n"
37: )
38: end
39: match = matcher.matches?(actual, &block)
40: ::Spec::Matchers.generated_description = "should not #{describe_matcher(matcher)}"
41: Spec::Expectations.fail_with(matcher.negative_failure_message) if match
42: end