    @Test
    public void height_givenLeftAndRightRandom() throws Exception {

        Random r = new Random();
        int h1 = r.nextInt(Integer.MAX_VALUE);
        int h2 = r.nextInt(Integer.MAX_VALUE);
        setField(node().withHeight(h1), "right");
        setField(node().withHeight(h2), "left");
        Assert.assertEquals(Math.max(h1, h2) + 1, test.height());
    }