assertTrue(result.startsWith("NtlmChallenge[challenge=0x"));
            assertTrue(result.endsWith(",dc=SERVER123]"));

            // Hexdump.toHexString with size = length * 2 produces 8 uppercase hex chars
            // The hex should be "010203FF"
            assertTrue(result.contains("010203FF"));
        }

        @Test
        @DisplayName("toString with empty challenge array")

        assertNotNull(result);
        // Hexdump uses uppercase letters
        // Note: completionFilter is displayed with 4 hex chars, not 8
        assertTrue(result.contains("fid=0xFFFF"));
        assertTrue(result.contains("filter=0xFFFF")); // Only 4 hex chars are shown
        assertTrue(result.contains("watchTree=true"));
    }

    @Test
    @DisplayName("Test toString method with zero values")

            int i = 0;
            do {
                if (i >= buf.length) {
                    final char[] nb = new char[buf.length * 2];
                    System.arraycopy(buf, 0, nb, 0, buf.length);
                    buf = nb;
                }
                buf[i++] = (char) peekc;
                peekc = read();
                peekct = peekc < 0 ? CT_WHITESPACE : peekc < 256 ? ctype[peekc] : CT_ALPHA;

        Field passwordField = NtlmPasswordAuthenticator.class.getDeclaredField("password");
        passwordField.setAccessible(true);

        char[] originalPassword = (char[]) passwordField.get(authenticator);
        char[] clonedPassword = (char[]) passwordField.get(cloned);

        assertNotSame(originalPassword, clonedPassword, "Cloned password should be a different array instance");

            final char originalChar1 = sb.charAt(i);
            final char originalChar2 = sb.charAt(i + 1);
            final char margedChar = mergeChar(originalChar1, originalChar2);
            if (margedChar != originalChar1) {
                sb.setCharAt(i, margedChar);
                sb.deleteCharAt(i + 1);
            } else {

    }

    /**
     * Test password in equals method
     */
    @Test
    public void testEqualsWithSecurePassword() {
        char[] password1 = "TestPass123!".toCharArray();
        char[] password2 = "TestPass123!".toCharArray();
        char[] password3 = "DifferentPass!".toCharArray();

        NtlmPasswordAuthenticator auth1 = new NtlmPasswordAuthenticator("DOMAIN", "user", password1);

     * @return the detected delimiter character
     */
    protected Character detectDelimiter(final String line) {
        final char[] candidates = { ',', '\t', ';', '|' };
        int maxCount = 0;
        char bestDelimiter = ',';

        for (final char candidate : candidates) {
            final int count = countOccurrences(line, candidate);
            if (count > maxCount) {

            buffer[i] = (short) 0;
        }
    }

    @Override
    public String toString() {
        final int len = length / 2 - (zterm ? 1 : 0);
        final char[] ca = new char[len];
        for (int i = 0; i < len; i++) {
            ca[i] = (char) buffer[i];
        }
        return new String(ca, 0, len);
    }

        assertNotNull(constantTimeMethod, "constantTimeEquals method should exist");
        constantTimeMethod.setAccessible(true);

        // Test the method directly
        char[] password1 = "testpassword".toCharArray();
        char[] password2 = "testpassword".toCharArray();
        char[] password3 = "testpassworX".toCharArray();

        assertEquals('N', (char) type2Bytes[0]);
        assertEquals('T', (char) type2Bytes[1]);
        assertEquals('L', (char) type2Bytes[2]);
        assertEquals('M', (char) type2Bytes[3]);
        assertEquals('S', (char) type2Bytes[4]);
        assertEquals('S', (char) type2Bytes[5]);
        assertEquals('P', (char) type2Bytes[6]);
        assertEquals(0, type2Bytes[7]); // Null terminator