assertTrue(result.contains("dc=TESTDC"));
        }

        @Test
        @DisplayName("toString with null challenge throws NPE")
        void testToStringWithNullChallengeThrowsNPE() {
            UniAddress dc = mock(UniAddress.class);
            when(dc.toString()).thenReturn("ANYSERVER");

            NtlmChallenge nc = new NtlmChallenge(null, dc);