e.max = 10;
        range.value = 5;
        flush(function() {
          assert.equal(range.ratio, 50);
          done();
        });
      });

      test('set min', function(done) {
        range.min = 10
        range.max = 50;
        range.value = 30;
        flush(function() {
          assert.equal(range.ratio, 50);
          range.value = 0;
          flush(function() {
            assert.equal(range.value, range.min);
            done();
          });
        });
      });

      test('set step', 