---

### 2. FilenameExtractorEnhancedTest.java
**Purpose**: Test FilenameExtractor edge cases and new documentation.

**Key Test Areas**:
- Parameter handling (null, empty, missing)
- Special character handling
- Input stream validation (not consumption)
- Edge cases (long filenames, paths, whitespace)

**Test Count**: 10 tests

**Key Scenarios**:
- ✅ Valid filename extraction

import org.mockito.junit.jupiter.MockitoExtension;

@ExtendWith(MockitoExtension.class)
class SmbUnsupportedOperationExceptionTest {

    // Provides a variety of messages including edge cases
    static Stream<String> messages() {
        return Stream.of("custom message", "", " ", "αβγ", "x".repeat(1000), null);
    }

    @Test
    @DisplayName("Default constructor sets the expected message and no cause")

     * @throws SmbException If an SMB error occurs.
     */
    @ParameterizedTest(name = "Filter: {0}, File: {1}, Expected: {2}")
    @CsvSource({
            // Positive cases (should be accepted)
            "1, 1, true", // ATTR_READONLY
            "2, 2, true", // ATTR_HIDDEN
            "4, 4, true", // ATTR_SYSTEM
            "16, 16, true", // ATTR_DIRECTORY

package jcifs.smb1.smb1;

/**
 * Unit tests for {@link FileEntry}. The interface itself has no
 * implementation, so the tests exercise the contract via Mockito mocks.
 * Each method is exercised for normal inputs, extreme or edge cases, and
 * interaction verification.
 */
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNull;
import static org.mockito.Mockito.mock;

import org.mockito.Mock;
import org.mockito.junit.jupiter.MockitoExtension;

/**
 * Comprehensive test suite for NdrShort class
 * Tests construction, encoding, decoding, and edge cases
 */
@ExtendWith(MockitoExtension.class)
@DisplayName("NdrShort Test Suite")
class NdrShortTest {

    @Mock
    private NdrBuffer mockBuffer;

    @Nested
    @DisplayName("Constructor Tests")

            assertThrows(CIFSException.class, () -> ctx.initSecContext(buf, 2, 2));
        }

        @Test
        @DisplayName("initSecContext null token edge cases")
        void testInitSecContextNullToken() throws Exception {
            DummySSPContext ctx = new DummySSPContext(new byte[] { 1 }, false, null, null, 0, false);
            // len == 0 is allowed and returns empty token

    void mock_noInteractions() {
        // Arrange/Act: do nothing
        // Assert: verify no interactions
        verifyNoInteractions(mockEntry);
    }

    // --- Fake implementation tests (happy path and edge cases) ---

    @Test
    @DisplayName("Fake implementation returns provided values (happy path)")
    void fakeImplementation_happyPath() {
        // Arrange

        List<TermQuery> queryList = SuggestUtil.getTermQueryList(null, fields);
        assertNotNull(queryList);
        assertEquals(0, queryList.size());
    }

    // Additional tests for createSuggestTextId boundary cases
    @Test
    public void testCreateSuggestTextIdBoundaryExactly445() {
        // Create text that encodes to exactly 445 characters
        // Base64 encoding increases size by ~4/3, so original size should be ~333 bytes

class Trans2FindFirst2ResponseTest {

    private Trans2FindFirst2Response response;

    @BeforeEach
    void setUp() {
        response = new Trans2FindFirst2Response();
    }

    // Test cases for SmbFindFileBothDirectoryInfo inner class
    @Test
    void testSmbFindFileBothDirectoryInfo_Getters() {
        Trans2FindFirst2Response.SmbFindFileBothDirectoryInfo info = response.new SmbFindFileBothDirectoryInfo();

/**
 * Tests for SMBProtocolDowngradeException covering all constructors and behaviors.
 */
@ExtendWith(MockitoExtension.class)
class SMBProtocolDowngradeExceptionTest {

    /**
     * Provides messages including edge cases (null and empty) for parameterized testing.
     */
    static Stream<Arguments> messages() {
        return Stream.of(Arguments.of((String) null), Arguments.of(""), Arguments.of("unexpected downgrade"));
    }

    @Test