// test a build where projects use different versions of the same plugin

    @Test
    void testThatPluginDependencyThatHasSystemScopeIsResolved() throws Exception {
        MavenSession session = createMavenSession(getProject("project-contributing-system-scope-plugin-dep"));
        MavenProject project = session.getCurrentProject();
        Plugin plugin = project.getPlugin("org.apache.maven.its.plugins:maven-it-plugin");

        Maven maven = getContainer().lookup(Maven.class);
        MavenExecutionRequest request =
                createMavenExecutionRequest(getProject("simple")).setGoals(asList("validate"));

        MavenExecutionResult result = maven.execute(request);
        assertNotNull(result);

        Class<?> wsrClass = wsrClassCatcher.wsrClassRef.get();

        ProjectBuildingRequest request = injectSession(toRequest(configuration));

        try {
            return projectBuilder.build(pom, request).getProject();
        } catch (ProjectBuildingException e) {
            throw transformError(e);
        }
    }

    // This is used by the SITE plugin.
    @Override

            MavenExecutionRequest request, ProjectBuildingException exception) {
        return exception.getResults().stream()
                .map(ProjectBuildingResult::getProject)
                .filter(Objects::nonNull)
                .filter(project -> request.getPom().equals(project.getFile()))
                .findFirst()
                .map(requestPomProject -> {

                }

                @Nonnull
                @Override
                public Optional<Project> getProject() {
                    return Optional.ofNullable(session.getProject(res.getProject()));
                }

                @Nonnull
                @Override
                public Collection<BuilderProblem> getProblems() {

        scopesToCollectForAggregatedProjects = Collections.synchronizedSet(new TreeSet<>());
        scopesToResolveForAggregatedProjects = Collections.synchronizedSet(new TreeSet<>());
    }

    public MavenProject getProject() {
        return project;
    }

    public Collection<String> getScopesToCollectForCurrentProject() {
        return scopesToCollectForCurrentProject;
    }

        } finally {
            Thread.currentThread().setContextClassLoader(ttcl);
        }
    }

    public InternalMavenSession getSession() {
        return session;
    }

    public MavenProject getProject() {
        return project;
    }

    @Nonnull
    @Override
    public String getGroupId() {
        return project.getGroupId();
    }

    @Nonnull
    @Override

            MavenProject child1Project = result1.getProject();

            // Capture repositories after building child1

            // Build child2 using the same shared request
            ProjectBuildingResult result2 = projectBuilder.build(child2Pom.toFile(), sharedRequest);
            MavenProject child2Project = result2.getProject();

            // Capture repositories after building child2

    Session getSession();

    /**
     * Gets the current project (if any).
     *
     * @return the current project or {@code empty()} if not applicable
     */
    @Nonnull
    Optional<Project> getProject();

    /**
     * Gets the current mojo execution (if any).
     *
     * @return the current mojo execution or {@code empty()} if not applicable
     */
    @Nonnull

        ModelSource modelSource = new UrlModelSource(DefaultMaven.class.getResource("project/standalone.xml"));
        MavenProject project =
                projectBuilder.build(modelSource, buildingRequest).getProject();
        project.setExecutionRoot(true);
        request.setProjectPresent(false);

        return Arrays.asList(project);
    }