int dstIndex = 50;

        // Act
        int result = response.writeSetupWireFormat(dst, dstIndex);

        // Assert
        assertEquals(0, result);
    }

    @Test
    @DisplayName("writeParametersWireFormat should return 0")
    void testWriteParametersWireFormat() {
        // Arrange
        byte[] dst = new byte[100];
        int dstIndex = 0;

        // Act

    }

    @Test
    @DisplayName("Default constructor sets the expected message and no cause")
    void defaultConstructor_setsExpectedMessage_andNoCause() {
        // Arrange & Act
        SmbUnsupportedOperationException ex = new SmbUnsupportedOperationException();

        // Assert
        assertEquals("Operation is not supported with the negotiated capabilities", ex.getMessage(),

            MsrpcSamrOpenAlias rpc = invocation.getArgument(0);
            rpc.retval = 0; // Simulate success
            return null;
        }).when(mockDcerpcHandle).sendrecv(any(MsrpcSamrOpenAlias.class));

        // Act
        SamrAliasHandle aliasHandle = new SamrAliasHandle(mockDcerpcHandle, mockSamrDomainHandle, access, rid);

        // Assert
        assertNotNull(aliasHandle);

        // Act
        out.close();

        // Assert
        verifyNoInteractions(handle);
    }

    @Nested
    @DisplayName("Constructor invalid inputs")
    class ConstructorInvalidInputs {
        @Test
        @DisplayName("Null handle triggers NullPointerException")
        void ctor_nullHandle_throwsNPE() {
            // Act + Assert

            // Act & Assert
            assertDoesNotThrow(() -> new MsrpcSamrConnect2(null, 0, ph));
        }

        @Test
        @DisplayName("should accept negative access mask values")
        void testNegativeAccessMaskAccepted() {
            // Arrange
            SamrPolicyHandle ph = createMockPolicyHandle();

            // Act & Assert

    @MethodSource("intErrorCodes")
    @DisplayName("int ctor: sets message and NT status as expected")
    void intConstructor_populatesMessageAndStatus(int errCode, int expectedStatus) {
        // Arrange & Act: create exception with error code
        SmbAuthException ex = new SmbAuthException(errCode);

        // Assert: type, message derived from code, status mapping, and no cause
        assertNotNull(ex);

        // Act
        tree.connectLogon(context);

        // Assert - verify interaction with dependency
        verify(tree, times(1)).connectLogon(context);
        verify(tree, never()).close();
    }

    @Test
    @DisplayName("connectLogon accepts null context but still invokes")
    void connectLogon_withNull_isInvoked() throws Exception {
        // Act
        tree.connectLogon(null);

        byte[] buf = new byte[4];

        // Act/Assert
        assertThrows(ArrayIndexOutOfBoundsException.class, () -> req.writeBytesWireFormat(buf, -1));
    }

    @Test
    @DisplayName("readBytesWireFormat returns 0 and tolerates null buffer")
    void readBytesWireFormat_returnsZeroEvenWithNull() {
        // Arrange
        Smb2LogoffRequest req = newRequest();

        // Act

    @Test
    @DisplayName("Constructor accepts a Configuration and creates instance")
    void constructor_happyPath() {
        // Arrange
        Configuration cfg = Mockito.mock(Configuration.class);

        // Act
        Smb2LogoffResponse resp = new Smb2LogoffResponse(cfg);

        // Assert
        assertNotNull(resp, "Response instance should be created");
    }

    @Nested
    @DisplayName("writeBytesWireFormat")

        boolean guest = flags[1];

        // Arrange
        Subject subject = new Subject();
        TestCredentials creds = new TestCredentials("DOMAIN", anonymous, guest, subject, false);

        // Act & Assert
        // unwrap to interface itself should return same instance
        CredentialsInternal unwrapped = creds.unwrap(CredentialsInternal.class);