clone.setResolved(artifact.isResolved());
        clone.setFile(artifact.getFile());

        clone.setAvailableVersions(copyList(artifact.getAvailableVersions()));
        if (artifact.getVersion() != null) {
            clone.setBaseVersion(artifact.getBaseVersion());
        }
        clone.setDependencyFilter(artifact.getDependencyFilter());

        assertEquals(p.getActivation().getPackaging(), clone.getActivation().getPackaging());
        assertEquals(p.getProperties(), clone.getProperties());
        assertEquals(p.getRepositories().size(), clone.getRepositories().size());
        // TODO deep compare the lists
        assertEquals(
                p.getPluginRepositories().size(), clone.getPluginRepositories().size());

        MavenProject clonedProject = projectToClone.clone();
        assertEquals(projectToClone.getFile(), clonedProject.getFile(), "POM file is preserved across clone");
        assertEquals(
                projectToClone.getBasedir(), clonedProject.getBasedir(), "Base directory is preserved across clone");
    }

    @Test
    void testUndefinedOutputDirectory() throws Exception {

    @Override
    public MavenSession clone() {
        try {
            MavenSession clone = (MavenSession) super.clone();
            // the default must become the current project of the thread that clones this
            MavenProject current = getCurrentProject();
            // we replace the thread local of the clone to prevent write through and enforce the new default value

     * @since 2.0.9
     */
    @Override
    public MavenProject clone() {
        MavenProject clone;
        try {
            clone = (MavenProject) super.clone();
        } catch (CloneNotSupportedException e) {
            throw new UnsupportedOperationException(e);
        }

        clone.deepCopy(this);

        return clone;
    }

    public void setModel(Model model) {

        request.setPluginGroups(settings.getPluginGroups());

        request.setLocalRepositoryPath(settings.getLocalRepository());

        for (Server server : settings.getServers()) {
            server = server.clone();

            request.addServer(server);
        }

        //  <proxies>
        //    <proxy>
        //      <active>true</active>
        //      <protocol>http</protocol>

                    if (desc == null) {
                        desc = supplier.load();
                        descriptors.putIfAbsent(key, clone(desc));
                    }
                }
            }
            return clone(desc);
        } catch (PluginDescriptorParsingException | PluginResolutionException | InvalidPluginDescriptorException e) {
            throw e;
        }
    }

 * ProjectBuildList.getByTaskSegments). Or maybe they should be introduced in the calculation
 * of the execution plan instead, which seems much nicer.
 * </p>
 * <p>
 * Additionally this class contains a clone of the MavenSession, which is *only* needed
 * because it has as notion of a "current" project.
 * </p>
 * <strong>NOTE:</strong> This class is not part of any public api and can be changed or deleted without prior notice.
 *

                Plugin plugin,
                DependencyFilter extensionFilter,
                List<RemoteRepository> repositories,
                RepositorySystemSession session) {
            this.plugin = plugin.clone();
            workspace = RepositoryUtils.getWorkspace(session);
            this.localRepo = session.getLocalRepository();
            this.repositories = new ArrayList<>(repositories.size());

    }

    XmlNode merge(@Nullable XmlNode source, @Nullable Boolean childMergeOverride);

    /**
     * Merge recessive into dominant and return either {@code dominant}
     * with merged information or a clone of {@code recessive} if
     * {@code dominant} is {@code null}.
     *
     * @param dominant the node
     * @param recessive if {@code null}, nothing will happen
     * @return the merged node
     */