}

    // Edge / invalid: null referral or empty/blank path
    @Test
    @DisplayName("handleDFSReferral handles null referral and empty path")
    void handleDfsReferralNullAndEmpty() {
        when(locator.handleDFSReferral(null, "")).thenReturn("smb://server/share/");
        assertEquals("smb://server/share/", locator.handleDFSReferral(null, ""));
        verify(locator).handleDFSReferral(null, "");

    void nullOptions_throwOnAccess() {
        // Arrange
        StaticJAASConfiguration cfg = new StaticJAASConfiguration(null);

        // Act + Assert
        assertThrows(IllegalArgumentException.class, () -> cfg.getAppConfigurationEntry("any"),
                "JAAS AppConfigurationEntry requires non-null options");
    }

    @Test

            final byte[] unicodeHash) {
        if (domain == null || username == null || ansiHash == null || unicodeHash == null) {
            throw new IllegalArgumentException("External credentials cannot be null");
        }
        this.domain = domain;
        this.username = username;
        this.password = null;
        this.challenge = challenge;
        this.ansiHash = ansiHash;

    @Test
    @DisplayName("Constructor with null file ID should accept null")
    void testConstructorWithNullFileId() {
        // Should not throw exception
        Smb2CloseRequest requestWithNull = new Smb2CloseRequest(mockConfig, null, testFileName);
        assertNotNull(requestWithNull);
    }

    @Test
    @DisplayName("Constructor with null fileName should accept null")

        // Test with null values
        result = jobExecutor.execute(null, "script");
        assertEquals("Executed: null script", result);

        result = jobExecutor.execute("type", null);
        assertEquals("Executed: type null", result);

        result = jobExecutor.execute(null, null);
        assertEquals("Executed: null null", result);

        // Test with empty strings

        return toDouble(o, null);
    }

    /**
     * Converts to {@link Double}.
     *
     * @param o
     *            The object to convert
     * @param pattern
     *            The pattern string
     * @return The converted {@link Double}
     */
    public static Double toDouble(final Object o, final String pattern) {
        if (o == null) {
            return null;

    @Test
    @DisplayName("Constructor with open() returning null closes immediately and hasNext=false")
    void constructorOpenNullCloses() throws Exception {
        // Arrange
        stubAcquireReturnsSelf();
        List<FileEntry[]> pages = List.of(new FileEntry[][] { new FileEntry[] {} });

        // Create iterator where open() returns null by giving null initial

      responseDone = true,
      socketSinkDone = true,
      socketSourceDone = true,
      e = null,
    )
  }

  private fun trackFailure(e: IOException) {
    hasFailure = true
    codec.carrier.trackFailure(call, e)
  }

  /** If [e] is non-null, this will return a non-null value. */
  fun bodyComplete(
    bytesRead: Long = -1L,
    isSocket: Boolean,
    responseDone: Boolean = false,

        if (text == null) {
            return null;
        }
        String tmp = text;
        for (final Normalizer normalizer : normalizers) {
            tmp = normalizer.normalize(tmp, field, langs);
            if (tmp == null) {
                return null;
            }
        }
        return tmp;
    }

    /**

            assertThrows(NullPointerException.class, () -> concreteImplementation.combine(null));
        }

        @Test
        @DisplayName("Should handle null in append")
        void testAppendWithNull() {
            // Test with mock
            doNothing().when(mockReferralData).append(null);
            assertDoesNotThrow(() -> mockReferralData.append(null));