module Test::Unit::ExceptionHandler

def exception_handlers
  @@exception_handlers
end

def included(base)
  base.extend(ClassMethods)
  observer = Proc.new do |test_case, _, _, value, method_name|
    if value
      @@exception_handlers.unshift(method_name)
    else
      @@exception_handlers.delete(method_name)
    end
  end
  base.register_attribute_observer(:exception_handler, &observer)
end