null, // effectiveModel is null
                null, // rawModel is null
                createMockModel("com.example", "test-project", "1.0.0") // fileModel is available
                );

        String projectId = (String) extractProjectIdMethod.invoke(null, mockResult);

        assertNotNull(projectId, "Project ID should not be null");
        assertEquals(

                }
            """
        ) {
            assertHasErrors(
                "Method com.example.Source.foo(): From non-null returning to null-unmarked returning breaking change.",
                "Method com.example.Source.baz(): From non-null returning to null-unmarked returning breaking change.",
            )
            assertHasNoWarning()

    }
    // ------------------------------------------------------------------------
    public MetadataGraphVertex addVertex(ArtifactMetadata md) {
        if (md == null) {
            return null;
        }

        checkVertices();

        MetadataGraphVertex v = findVertex(md);
        if (v != null) {
            return v;
        }

        v = new MetadataGraphVertex(md);

        return treeRoot == null ? null : new MetadataGraph(treeRoot);
    }
    // ----------------------------------------------------------------------------
    public MetadataGraph getGraph(ArtifactScopeEnum scope)
            throws MetadataResolutionException, GraphConflictResolutionException {
        if (treeRoot == null) {
            return null;
        }

        if (conflictResolver == null) {

        this.groupId = (groupId != null && !groupId.isEmpty()) ? groupId : null;
        this.artifactId = (artifactId != null && !artifactId.isEmpty()) ? artifactId : null;
        this.classifier = (classifier != null && !classifier.isEmpty()) ? classifier : null;
        this.extension = (extension != null && !extension.isEmpty()) ? extension : null;

        if (model == null) {
            return "";
        }

        String groupId = model.getGroupId();
        if (groupId == null && model.getParent() != null) {
            groupId = model.getParent().getGroupId();
        }

        String artifactId = model.getArtifactId();

        String version = model.getVersion();
        if (version == null && model.getParent() != null) {

    // Mixed case.
    checkPublicSuffix("COM", null)
    checkPublicSuffix("example.COM", "example.com")
    checkPublicSuffix("WwW.example.COM", "example.com")
    // Leading dot.
    checkPublicSuffix(".com", null)
    checkPublicSuffix(".example", null)
    checkPublicSuffix(".example.com", null)
    checkPublicSuffix(".example.example", null)
    // Unlisted TLD.
    checkPublicSuffix("example", null)

  request: Request,
) : RoutePlanner {
  private val doExtensiveHealthChecks = request.method != "GET"
  private var routeSelection: RouteSelector.Selection? = null
  private var routeSelector: RouteSelector? = null
  private var nextRouteToTry: Route? = null

  override val deferredPlans = ArrayDeque<Plan>()

  override fun isCanceled(): Boolean = call.isCanceled()

  @Throws(IOException::class)

     *
     * @param modelSource The source of the POM to process, may be {@code null}.
     * @return This request, never {@code null}.
     */
    ModelBuildingRequest setModelSource(ModelSource modelSource);

    /**
     * Gets the POM file of the project to build.
     *
     * @return The POM file of the project or {@code null} if not applicable (i.e. when processing a POM from the
     *         repository).
     */

     * @param algorithms  The checksum algorithms to use, must not be {@code null}.
     * @return The calculated checksums, indexed by algorithms, never {@code null}.
     * @throws NullPointerException if passed in any parameter is {@code null}.
     * @throws IOException In case of any IO problem.
     */
    @Nonnull