toDelete.add(new Node());
        toDelete.add("test");
        assertFalse(elements.removeAll(toDelete));
        assertSame(parent, child.getParent());
        toDelete.add(child);
        assertTrue(elements.removeAll(toDelete));
        // Check if node was correctly detached from elements
        assertEquals(0, elements.size());
        assertNull(child.getParent());
        assertNull(child.getDocument());