modified.set(parent.withVersion(newVersion));
            }

            return resolveModel(parent.getGroupId(), parent.getArtifactId(), newVersion);
        } catch (final VersionRangeResolutionException e) {
            throw new UnresolvableModelException(
                    e.getMessage(), parent.getGroupId(), parent.getArtifactId(), parent.getVersion(), e);
        }
    }

    @Override

        }

        return null;
    }

    public List<String> findVersions(Artifact artifact) {
        List<String> versions = getProjects()
                .getOrDefault(artifact.getGroupId(), Collections.emptyMap())
                .getOrDefault(artifact.getArtifactId(), Collections.emptyMap())
                .values()
                .stream()
                .map(MavenProject::getVersion)

    // ----------------------------------------------------------------------

    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        if (getGroupId() != null) {
            sb.append(getGroupId());
            sb.append(':');
        }
        appendArtifactTypeClassifierString(sb);
        sb.append(':');
        if (getBaseVersionInternal() != null) {

     */
    static boolean isInScope(Artifact artifact, Artifact nodeArtifact) {
        return Objects.equals(artifact.getGroupId(), nodeArtifact.getGroupId())
                && Objects.equals(artifact.getArtifactId(), nodeArtifact.getArtifactId())
                && Objects.equals(artifact.getVersion(), nodeArtifact.getVersion());
    }

                    }

                    if (relocation != null) {
                        if (relocation.getGroupId() != null) {
                            artifact.setGroupId(relocation.getGroupId());
                            relocatedArtifact = artifact;
                            project.setGroupId(relocation.getGroupId());
                        }
                        if (relocation.getArtifactId() != null) {

    }

    private CoreExtensionEntry createExtension(CoreExtension extension, List<Artifact> artifacts) throws Exception {
        String realmId = "coreExtension>" + extension.getGroupId() + ":" + extension.getArtifactId() + ":"
                + extension.getVersion();
        final ClassRealm realm = classWorld.newRealm(realmId, null);
        Set<String> providedArtifacts = Collections.emptySet();

        if (RELEASE.equals(version)) {
            metadata = new DefaultMetadata(
                    artifact.getGroupId(), artifact.getArtifactId(), MAVEN_METADATA_XML, Metadata.Nature.RELEASE);
        } else if (LATEST.equals(version)) {
            metadata = new DefaultMetadata(
                    artifact.getGroupId(),
                    artifact.getArtifactId(),
                    MAVEN_METADATA_XML,

        // prepare
        File basedir = new File("").getAbsoluteFile();
        ExecutionEvent event = mock(ExecutionEvent.class);
        MavenProject project = mock(MavenProject.class);
        when(project.getGroupId()).thenReturn("org.apache.maven");
        when(project.getArtifactId()).thenReturn("maven-embedder");
        when(project.getPackaging()).thenReturn("jar");
        when(project.getName()).thenReturn("Apache Maven Embedder");

        return (extension ? "extension>" : "plugin>") + plugin.getGroupId() + ":" + plugin.getArtifactId() + ":"
                + version;
    }

    private static String getId(Artifact artifact) {
        return getId(
                artifact.getGroupId(),
                artifact.getArtifactId(),
                artifact.getExtension(),

         * plugins only check for null, so be sure to nullify an empty classifier.
         */
        org.apache.maven.artifact.Artifact result = new org.apache.maven.artifact.DefaultArtifact(
                artifact.getGroupId(),
                artifact.getArtifactId(),
                artifact.getVersion(),
                null,
                artifact.getProperty(ArtifactProperties.TYPE, artifact.getExtension()),