       '{"message": "an error has occurred"}'
          ]
        );

        ajax = fixture('TrivialGet');
      });

      teardown(function() {
        server.restore();
      });

      // Echo requests are responded to individually and on demand, unlike the
      // others in this file which are responded to with server.respond(),
      // which responds to all open requests.
      // We don't use server.respondWith here because there's no way to use it
      // and only respond to a subset of requests