chain.delete(user);

        assertEquals(1, chain.deleteCalls.size());
        assertEquals(user, chain.deleteCalls.get(0));
    }

    // Test delete with null user
    @Test
    public void test_delete_nullUser() {
        TestAuthenticationChain chain = new TestAuthenticationChain();

        chain.delete(null);

        assertEquals(1, chain.deleteCalls.size());
        assertNull(chain.deleteCalls.get(0));