find_rescue_handler

# File activesupport/lib/active_support/rescuable.rb, line 124
        def find_rescue_handler(exception)
          if exception
            # Handlers are in order of declaration but the most recently declared
            # is the highest priority match, so we search for matching handlers
            # in reverse.
            _, handler = rescue_handlers.reverse_each.detect do |class_or_name, _|
              if klass = constantize_rescue_handler_class(class_or_name)
                klass === exception
              end
            end

            handler
          end
        end