@Test
    public void testSetTwice() {
        ObservableList<Integer> original = FXCollections.observableArrayList(
                0, 1, 2, 3, 4 ,5, 6, 7, 8, 9
        );
        SortedList list = new SortedList(original);
        original.set(0, 10);
        // that's the internal culprit, book-keeping gone wrong
        assertEquals(original.size(), list.size());
       // following line throws an AIOOB, that's what seen in UIs, f.i. when committing edits
        original.set(0, 10);
    }