if (extensionRecord == null) {
            ClassRealm extensionRealm = classRealmManager.createExtensionRealm(plugin, toAetherArtifacts(artifacts));

            // TODO figure out how to use the same PluginDescriptor when running mojos

            PluginDescriptor pluginDescriptor = null;
            if (plugin.isExtensions() && !artifacts.isEmpty()) {

            return getProjectAExecutionPlan();
        }
        if (project.equals(ProjectDependencyGraphStub.B)) {
            return getProjectBExecutionPlan();
        }
        // The remaining are basically "for future expansion"
        List<MojoExecution> me = new ArrayList<>();
        me.add(createMojoExecution("resources", "default-resources", PROCESS_RESOURCES));
        me.add(createMojoExecution("compile", "default-compile", COMPILE));

    @Override
    public ModelSource resolveModel(final Parent parent, AtomicReference<Parent> modified)
            throws UnresolvableModelException {
        Result result;
        try {
            Future<Result> future = parentCache.computeIfAbsent(parent.getId(), id -> {
                ForkJoinPool pool = new ForkJoinPool(MAX_CAP);
                ForkJoinTask<Result> task = new ForkJoinTask<>() {
                    Result result;

        File artifactFile = new File(repository.getBasedir(), path);

        if (artifactFile.exists()) {
            if (!artifactFile.delete()) {
                throw new IOException("Failure while attempting to delete artifact " + artifactFile);
            }
        }
    }

    protected DefaultRepositorySystemSession initRepoSession() throws Exception {

        } catch (LookupException e) {
            return addExceptionToResult(result, e);
        }

        eventCatapult.fire(ExecutionEvent.Type.ProjectDiscoveryStarted, session, null);

        Result<? extends ProjectDependencyGraph> graphResult = buildGraph(session);

        if (graphResult.hasErrors()) {

        wagonManager.getArtifact(artifact, repo, null, false);

        wagon.clearExpectedContent();
        wagon.addExpectedContent("path", "expected-failure");
        wagon.addExpectedContent("path.sha1", "b7bb97d7d0b9244398d9b47296907f73313663e6");
        assertThrows(
                ChecksumFailedException.class,

                    // don't stop processing in case a future segment explicitly excludes this repo
                }
                // check for external:http:*
                else if (EXTERNAL_HTTP_WILDCARD.equals(repo) && isExternalHttpRepo(originalRepository)) {
                    result = true;
                    // don't stop processing in case a future segment explicitly excludes this repo

    int LOGGING_LEVEL_FATAL = Logger.LEVEL_FATAL;

    int LOGGING_LEVEL_DISABLED = Logger.LEVEL_DISABLED;

    // ----------------------------------------------------------------------
    // Reactor Failure Mode
    // ----------------------------------------------------------------------

    String REACTOR_FAIL_FAST = "FAIL_FAST";

    String REACTOR_FAIL_AT_END = "FAIL_AT_END";

          <association>
            <type>Repository</type>
            <multiplicity>*</multiplicity>
          </association>
          <comment>
            This may be removed or relocated in the near
            future. It is undecided whether plugins really need a remote
            repository set of their own.
          </comment>
        </field>
        <field xdoc.separator="blank">
          <name>profiles</name>

                    "Cannot read metadata from '" + mappingFile + "': " + e.getMessage(), e);
        }
    }

    /**
     * Ensures the last updated timestamp of the specified metadata does not refer to the future and fixes the local
     * metadata if necessary to allow proper merging/updating of metadata during deployment.
     */
    private void fixTimestamp(File metadataFile, Metadata metadata, Metadata reference) {