@Override
    public ModelNodeInternal getLink(String name) {
        return target == null ? null : target.getLink(name);
    }

    @Override
    public Iterable<? extends ModelNodeInternal> getLinks() {
        return target == null ? Collections.<ModelNodeInternal>emptyList() : target.getLinks();
    }

    @Override
    public Iterable<? extends MutableModelNode> getLinks(Predicate<? super MutableModelNode> predicate) {

        def package2 = "package2"

        groovydoc.link(url1, package1)
        def newLinkSet = WrapUtil.toSet(new Groovydoc.Link(url2, package2))
        groovydoc.setLinks(newLinkSet)

        expect:
        groovydoc.getLinks() == newLinkSet
    }

    def "groovy classpath must not be empty"() {
        when:
        groovydoc.setGroovyClasspath(TestFiles.empty())
        groovydoc.generate()

    @Override
    public boolean hasLink(String name, ModelType<?> type) {
        return hasLink(name, withType(type));
    }

    @Override
    public Iterable<? extends MutableModelNode> getLinks(ModelType<?> type) {
        return getLinks(withType(type));
    }

    @Override
    public Set<String> getLinkNames(ModelType<?> type) {
        return getLinkNames(withType(type));
    }

    @Override

            queue.add(ancestor);
            while (!queue.isEmpty()) {
                ModelNodeInternal parent = queue.removeFirst();
                for (ModelNodeInternal node : parent.getLinks()) {
                    maybeNotify(node, listener);
                    queue.addFirst(node);
                }
            }
        }
        ancestorListeners.put(listener.getAncestor(), listener);
    }

        }

        @Override
        ModelNodeInternal getLink(String name) {
            return null
        }

        @Override
        int getLinkCount(Predicate<? super MutableModelNode> predicate) {
            return 0
        }

        @Override
        Iterable<? extends MutableModelNode> getLinks(Predicate<? super MutableModelNode> predicate) {
            return null
        }

        return links != null && links.containsKey(name);
    }

    @Override
    @Nullable
    public ModelNodeInternal getLink(String name) {
        return links == null ? null : links.get(name);
    }

    @Override
    public Iterable<? extends ModelNodeInternal> getLinks() {
        return links == null ? Collections.<ModelNodeInternal>emptyList() : links.values();
    }

    @Override

    @Nullable
    MutableModelNode getLink(String name);

    int getLinkCount(Predicate<? super MutableModelNode> predicate);

    Set<String> getLinkNames(Predicate<? super MutableModelNode> predicate);

    Set<String> getLinkNames();

    @Override
    Iterable<? extends MutableModelNode> getLinks(ModelType<?> type);

    Iterable<? extends MutableModelNode> getLinks(Predicate<? super MutableModelNode> predicate);

        if (modelNode != null && realized.compareAndSet(false, true)) {
            modelNode.ensureAtLeast(ModelNode.State.SelfClosed);
            for (MutableModelNode node : modelNode.getLinks(ModelType.of(type))) {
                node.ensureAtLeast(ModelNode.State.GraphClosed);
            }
        }
        for (T t : this) {
            context.add(t);
        }
    }

    @Override

     */
    <T> ModelView<? extends T> asImmutable(ModelType<T> type, @Nullable ModelRuleDescriptor ruleDescriptor);

    Set<String> getLinkNames(ModelType<?> type);

    Iterable<? extends ModelNode> getLinks(ModelType<?> type);

    /**
     * Should this node be hidden from the model report.
     */
    boolean isHidden();

    /**
     * The number of link this node has.
     */
    int getLinkCount();

        assertNull(options.getWindowTitle());
        assertNull(options.getDocTitle());
        assertNull(options.getFooter());
        assertNull(options.getBottom());
        assertEmpty(options.getLinks());
        assertEmpty(options.getLinksOffline());
        assertFalse(options.isLinkSource());
        assertEmpty(options.getGroups());
        assertFalse(options.isNoDeprecated());