}
            return true; // not reached in this test
        };

        // Act + Assert
        NullPointerException npe = assertThrows(NullPointerException.class, () -> filter.accept(null));
        assertEquals("file must not be null", npe.getMessage());
    }

    }

    // --- Invalid/null usage: calling a method on null should throw NPE ---
    @Test
    void nullReference_throwsNullPointerException() {
        // Arrange
        SmbBasicFileInfo info = null;

        // Act & Assert: attempting to call any method on null should throw NPE
        Assertions.assertThrows(NullPointerException.class, () -> {

                            return authInfo;
                        }
                    }
                }
            }
        }

        // empty one to prevent NPE
        return new AuthenticationInfo();
    }

    @Override
    public ProxyInfo getProxy(String protocol) {
        MavenSession session = legacySupport.getSession();

        shareInfo1.netname = "TestShare";
        shareInfo1.type = 1;
        shareInfo1.remark = "Test Remark";

        // Set up deferred buffer chain to avoid NPE
        mockDeferredBuffer.deferred = mockDeferredBuffer;

        shareInfo1.encode(mockNdrBuffer);

        // Verify the encode operations
        verify(mockNdrBuffer).align(4);

   * documentation.
   */
  public void add(Runnable runnable, Executor executor) {
    // Fail fast on a null. We throw NPE here because the contract of Executor states that it throws
    // NPE on null listener, so we propagate that contract up into the add method as well.
    checkNotNull(runnable, "Runnable was null.");
    checkNotNull(executor, "Executor was null.");

        }));
    }

    @ParameterizedTest(name = "Invalid usage causes NPE: {0}")
    @MethodSource("npePublicGetters")
    void getters_withoutTree_throwNPE(String name, org.junit.jupiter.api.function.Executable call) {
        // Each call is invalid without a held tree and should throw NPE
        assertThrows(NullPointerException.class, call);
    }

            assertEquals("smb1://", new SmbFile("smb1://server/").getParent());
            // Test parent of root - currently throws NPE due to bug in SmbFile.getParent()
            // when authority is null. This is a known issue in the legacy implementation.
            // For now, we expect the NPE to maintain backward compatibility
            assertThrows(NullPointerException.class, () -> new SmbFile("smb1://").getParent());
        }

     * {@link NullPointerException}. This test is defensive; in real code it
     * would likely be handled elsewhere.
     */
    @Test
    @DisplayName("calling getters on null reference throws NPE")
    void testNullReference() {
        AllocInfo nullRef = null;
        assertThrows(NullPointerException.class, () -> nullRef.getCapacity());
        assertThrows(NullPointerException.class, () -> nullRef.getFree());
    }

    @Override
    public Artifact find(Artifact artifact) {
        File artifactFile = new File(localRepository.getBasedir(), pathOf(artifact));

        // We need to set the file here or the resolver will fail with an NPE, not fully equipped to deal
        // with multiple local repository implementations yet.
        artifact.setFile(artifactFile);

        return artifact;
    }

    @Override
    public String getId() {

    }

    @Test
    @DisplayName("initSecContext with null buffer and non-zero len throws NPE")
    void testInitSecContextNullBufferNonZeroLen() throws Exception {
        SpnegoContext ctx = newContext();
        // A null buffer with non-zero len leads to NPE while slicing input
        assertThrows(NullPointerException.class, () -> ctx.initSecContext(null, 0, 1));