anchor.diff:              'fooLeave': 0,
               'fooEnter': 1,
             });
  -          router.route('/123?foo=bar').then((_) {
  +          return router.route('/123?foo=bar').then((_) {
               expect(counters, {
                 'fooLeave': 0,
                 'fooEnter': 1,
  
positive.code:             'fooLeave': 0,
              'fooEnter': 1,
            });
            router.route('/123?foo=bar').then((_) {
              expect(counters, {
                'fooLeave': 1,
                'fooEnter': 2,
  
negative.code:             'fooLeave': 0,
              'fooEnter': 1,
            });
            return router.route('/123?foo=bar').then((_) {
              expect(counters, {
                'fooLeave': 1,
                'fooEnter': 2,
  