return cl.call()
        }
    }

    def format(Node... nodes) {
        format(nodes as List)
    }

    def formatTree(Node... nodes) {
        formatTree(nodes as List)
    }

    def formatTree(Iterable<? extends Node> nodes) {
        format(nodes, true)
    }

    def format(Iterable<? extends Node> nodes, boolean prettyPrint = false) {
        StringBuilder builder = new StringBuilder()

        nodes.add(node);
    }

    /**
     * find a node by the GAV (metadata)
     *
     * @param md
     */
    public MetadataGraphNode findNode(MavenArtifactMetadata md) {
        for (MetadataGraphNode mgn : nodes) {
            if (mgn.metadata.equals(md)) {
                return mgn;
            }
        }

        MetadataGraphNode node = new MetadataGraphNode(md);
        addNode(node);

    protected abstract void doWrite(XmlNode node, Writer writer) throws IOException;

    /**
     * Implementation method for merging two XML nodes.
     *
     * @param dominant the dominant (higher priority) XML node
     * @param recessive the recessive (lower priority) XML node
     * @param childMergeOverride optional override for the child merge mode
     * @return the merged XML node, or null if both inputs are null
     */

    /**
     * Use an XPath string to select a single node.
     *
     * @param contextNode The node to start searching from.
     * @param expression A valid XPath string.
     * @return The first node found that matches the XPath, or null.
     *
     * @throws XPathExpressionException if an XPath expression error occurs.
     */

        // nodes must have a single output.
        if (node->num_outputs() != 1) {
          return InvalidArgument(
              "When `num_opers` is set to -1, nodes referenced in `inputs` "
              "must have a single output. Node ",
              node->name(), " has ", node->num_outputs(),
              " outputs. Encountered while creating function '", fn_name, "'");
        }
      }
    }

    name: str


class Labels(BaseModel):
    nodes: list[LabelNode]


class ReviewNode(BaseModel):
    author: Author | None = None
    state: str


class Reviews(BaseModel):
    nodes: list[ReviewNode]


class PullRequestNode(BaseModel):
    number: int
    labels: Labels
    author: Author | None = None
    title: str
    createdAt: datetime
    lastEditedAt: datetime | None = None

    for (Integer node : graph.nodes()) {
      assertThat(graph.adjacentNodes(node)).isEqualTo(asGraph.adjacentNodes(node));
      assertThat(graph.predecessors(node)).isEqualTo(asGraph.predecessors(node));
      assertThat(graph.successors(node)).isEqualTo(asGraph.successors(node));
      assertThat(graph.degree(node)).isEqualTo(asGraph.degree(node));
      assertThat(graph.inDegree(node)).isEqualTo(asGraph.inDegree(node));

    /**
     * Returns an immutable list of all child nodes.
     *
     * @return list of child nodes, never {@code null}
     */
    @Nonnull
    List<XmlNode> children();

    /**
     * Returns the first child node with the specified name.
     *
     * @param name the name of the child node to find
     * @return the first matching child node, or {@code null} if none found
     */
    @Nullable

 * @author Joshua O'Madadhain
 * @author Jens Nyman
 * @param <N> Node parameter type
 * @since 23.0
 */
@Beta
@DoNotMock("Implement with a lambda, or use GraphBuilder to build a Graph with the desired edges")
public interface SuccessorsFunction<N> {

  /**
   * Returns all nodes in this graph adjacent to {@code node} which can be reached by traversing
   * {@code node}'s outgoing edges in the direction (if any) of the edge.
   *

    for (Integer node : graph.nodes()) {
      assertThat(graph.adjacentNodes(node)).isEqualTo(asGraph.adjacentNodes(node));
      assertThat(graph.predecessors(node)).isEqualTo(asGraph.predecessors(node));
      assertThat(graph.successors(node)).isEqualTo(asGraph.successors(node));
      assertThat(graph.degree(node)).isEqualTo(asGraph.degree(node));
      assertThat(graph.inDegree(node)).isEqualTo(asGraph.inDegree(node));