@Test
  public void hasProgressWithoutSize() {
    t.setSize(0);
    t.setTransferred(0);

    assertEquals(0.0, t.getProgress(), PRECISION);
  }
 @Test
 public void knowsWhenItHasNoSize() {
   Transaction t = new DummyTransaction();
   t.setSize(0);
   assertFalse(t.hasSize());
 }