@Test
 public void testPassNull() {
   AssertObservable.assertObservableEqualsBlocking("foo", null, null);
 }
 @Test(expected = AssertionError.class)
 public void testFailNull() {
   AssertObservable.assertObservableEqualsBlocking("foo", Observable.just(1, 2), null);
 }
 @Test
 public void testPassNotNull() {
   AssertObservable.assertObservableEqualsBlocking(
       "foo", Observable.just(1, 2), Observable.just(1, 2));
 }