vertices = new TreeSet<>();
        }
    }

    private void checkEdges() {
        int count = DEFAULT_EDGES;

        if (vertices != null) {
            count = vertices.size() + vertices.size() / 2;
        }

        checkEdges(count);
    }

    private void checkEdges(int nEdges) {
        if (incidentEdges == null) {
            incidentEdges = new HashMap<>(nEdges);
        }

        graph = new Graph();

        // groupId:artifactId:version -> project
        projectMap = new HashMap<>(projects.size() * 2);

        // groupId:artifactId -> (version -> vertex)
        Map<String, Map<String, Vertex>> vertexMap = new HashMap<>(projects.size() * 2);

        for (MavenProject project : projects) {
            String projectId = getId(project);

        }

        @Override
        public boolean isNull() {
            return (size() == 0);
        }

        void normalize() {
            for (int i = size() - 1; i >= 0; i--) {
                Item lastItem = get(i);

                if (lastItem.isNull()) {
                    if (i == size() - 1 || get(i + 1).getType() == STRING_ITEM) {
                        remove(i);

        System.out.println("Result: " + depResults);

        assertNotNull(depResults);
        assertEquals(1, depResults.size());
        assertSame(depArtifact, depResults.get(0), "dependency artifact is wrong.");
    }

    @Test
    void testPluginArtifactMapExpressionReference() throws Exception {

    <!--
    This checks the coalescing of CHARACTERS events which would otherwise be reported in chunks of the internal parser
    buffer size (usually 4 or 8 KB). The text block is designed such that its length is exactly 32 KB after leading
    and trailing whitespace has been removed and all line terminators have been removed.
    -->
    <prop2>

            ClassLoader classLoader = Thread.currentThread().getContextClassLoader();

            CountDownLatch latch =
                    new CountDownLatch(result.getArtifactResolutionNodes().size());

            for (ResolutionNode node : result.getArtifactResolutionNodes()) {
                Artifact artifact = node.getArtifact();

                .withFailMessage("Expected result not to have errors")
                .isFalse();
        List<MavenProject> actualReactorProjects = result.get().getSortedProjects();
        assertEquals(2, actualReactorProjects.size());
        assertEquals("pom", actualReactorProjects.get(1).getPackaging());
    }

    @BeforeEach
    void before() throws Exception {
        graphBuilder = new DefaultGraphBuilder(

        assertNotNull(results);
        assertEquals(1, results.size());
        ProjectBuildingResult result = results.get(0);
        assertNotNull(result);
        assertNotNull(result.getProject());
        assertEquals(1, result.getProblems().size());
        assertEquals(1, result.getProject().getArtifacts().size());
        assertNotNull(result.getDependencyResolutionResult());
    }

    /**

                    project, scopesToCollect, scopesToResolve, session, aggregating, projectArtifacts);

            Map<Artifact, File> reactorProjects =
                    new HashMap<>(session.getProjects().size());
            for (MavenProject reactorProject : session.getProjects()) {
                reactorProjects.put(
                        reactorProject.getArtifact(),

        }

        if (metadata == null) {
            result.setVersion(version);
        } else {
            List<MetadataRequest> metadataReqs =
                    new ArrayList<>(request.getRepositories().size());

            metadataReqs.add(new MetadataRequest(metadata, null, request.getRequestContext()));

            for (RemoteRepository repository : request.getRepositories()) {