if (oldValue != null) {
        if (throwIfDuplicateKeys) {
          throw conflictException("key", entryArray[i], entryArray[i].getKey() + "=" + oldValue);
        }
        if (duplicates == null) {
          duplicates = new HashMap<>();
        }
        duplicates.put(key, value);
        dupCount++;
      }
    }
    if (duplicates != null) {
      @SuppressWarnings({"rawtypes", "unchecked"})

        Mockito.verifyNoMoreInteractions(mock);
    }

    // --- 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, () -> {

    private DefaultToolchainsReader reader = new DefaultToolchainsReader();

    @Test
    void testMergeNulls() {
        merger.merge(null, null, null);

        PersistedToolchains pt = new PersistedToolchains();
        merger.merge(pt, null, null);
        merger.merge(null, pt, null);
    }

    @Test
    void testMergeJdk() throws Exception {

                "test-grp", "test-artifact", VersionRange.createFromVersion("1.0"), "type", null, "system", "provided");
        Artifact artifact2 = factory.createDependencyArtifact(
                "test-grp", "test-artifact-2", VersionRange.createFromVersion("1.0"), "type", null, "system", "test");
        Artifact artifact3 = factory.createDependencyArtifact(
                "test-grp",

    public boolean equals(Object obj) {
        if (obj == null) {
            return false;
        }

        if (MetadataGraphNode.class.isAssignableFrom(obj.getClass())) {
            MetadataGraphNode node2 = (MetadataGraphNode) obj;

            if (node2.metadata == null) {
                return metadata == null;
            }

            return metadata != null && metadata.toString().equals(node2.metadata.toString());

      }

    fun build(): Cookie =
      Cookie(
        name ?: throw NullPointerException("builder.name == null"),
        value ?: throw NullPointerException("builder.value == null"),
        expiresAt,
        domain ?: throw NullPointerException("builder.domain == null"),
        path,
        secure,
        httpOnly,
        persistent,
        hostOnly,
        sameSite,
      )
  }

        }

        @Test
        @DisplayName("should handle null policy handle")
        void testNullPolicyHandleHandled() {
            // Act & Assert - The constructor accepts null policy handle without throwing
            assertDoesNotThrow(() -> new MsrpcSamrConnect2("\\\\srv", 0, null));
        }

        @Test
        @DisplayName("should handle empty string as system name")

    ImmutableList.Builder<String> builder = ImmutableList.builder();
    assertThrows(NullPointerException.class, () -> builder.add((String) null));

    assertThrows(NullPointerException.class, () -> builder.add((String[]) null));

    assertThrows(NullPointerException.class, () -> builder.add("a", null, "b"));
  }

  public void testBuilderAddAllHandlesNullsCorrectly() {
    {

    protected void assertObjectNotNull(String variableName, Object value) {
        if (variableName == null) {
            String msg = "The value should not be null: variableName=null value=" + value;
            throw new IllegalArgumentException(msg);
        }
        if (value == null) {
            String msg = "The value should not be null: variableName=" + variableName;
            throw new IllegalArgumentException(msg);
        }

        return "Type2Message[target=" + target + ",challenge=" + (challenge == null ? "null" : "<" + challenge.length + " bytes>")
                + ",context=" + (context == null ? "null" : "<" + context.length + " bytes>") + ",targetInformation="
                + (targetInformation == null ? "null" : "<" + targetInformation.length + " bytes>") + ",flags=0x"