if (request.getUserProperties().containsKey(REVISION_PROPERTY)) {
            modelProperties.put(REVISION_PROPERTY, request.getUserProperties().get(REVISION_PROPERTY));
        }
        if (request.getUserProperties().containsKey(CHANGELIST_PROPERTY)) {
            modelProperties.put(CHANGELIST_PROPERTY, request.getUserProperties().get(CHANGELIST_PROPERTY));
        }

        String revision = request.getUserProperties().getProperty("revision");
        assertEquals("8.2.0", revision);

        assertEquals("bar ", request.getUserProperties().getProperty("foo"));
        assertEquals("bar two", request.getUserProperties().getProperty("foo2"));
        assertEquals("Apache Maven", request.getUserProperties().getProperty("label"));

     */
    @Nonnull
    default Builder toBuilder() {
        try {
            return new Builder(
                    getUserProperties(), getSystemProperties(), getStartTime(), getTopDirectory(), getRootDirectory());
        } catch (IllegalStateException e) {
            return new Builder(getUserProperties(), getSystemProperties(), getStartTime(), getTopDirectory(), null);
        }
    }

    /**

        // single one
        request.getUserProperties().put("maven.session.versionFilter", "s");
        versionFilter = systemSessionFactory.newRepositorySession(request).getVersionFilter();
        assertNotNull(versionFilter);
        assertInstanceOf(ContextualSnapshotVersionFilter.class, versionFilter);

        request.getUserProperties().put("maven.session.versionFilter", "h");

                .toList();
    }

    @Nonnull
    @Override
    public Map<String, String> getUserProperties() {
        return Collections.unmodifiableMap(new PropertiesAsMap(getMavenSession().getUserProperties()));
    }

    @Nonnull
    @Override
    public Map<String, String> getSystemProperties() {

     */
    @Nonnull
    Map<String, String> getSystemProperties();

    /**
     * Provides a map of user properties.
     * User properties
     */
    @Nonnull
    Map<String, String> getUserProperties();

    @Nonnull
    RepositoryMerging getRepositoryMerging();

    @Nullable
    ModelTransformer getLifecycleBindingsInjector();

    @Nonnull

            request.setRepositorySession(session.getRepositorySession());
            request.setSystemProperties(session.getSystemProperties());
            if (request.getUserProperties().isEmpty()) {
                request.setUserProperties(session.getUserProperties());
            }

            MavenExecutionRequest req = session.getRequest();
            if (req != null) {

        request.setSystemProperties(systemProperties);

        return this;
    }

    @Override
    public Properties getUserProperties() {
        return request.getUserProperties();
    }

    @Override
    public FilterModelBuildingRequest setUserProperties(Properties userProperties) {
        request.setUserProperties(userProperties);

     * line.
     *
     * @return The user properties, never {@code null}.
     */
    public Properties getUserProperties() {
        return request.getUserProperties();
    }

    /**
     * Gets the system properties to use for interpolation and profile activation. The system properties are collected

 */
@Deprecated(since = "4.0.0")
public interface ProfileActivationContext {
    /**
     * Key of the property containing the project's packaging.
     * Available in {@link #getUserProperties()}.
     * @since 3.9
     */
    String PROPERTY_NAME_PACKAGING = "packaging";

    /**
     * Gets the identifiers of those profiles that should be activated by explicit demand.
     *