.collect(Collectors.toMap(MavenProject::getArtifactId, identity()));

        // Set dependencies and modules
        projectModuleB.setDependencies(singletonList(toDependency(projectModuleA)));
        projectModuleC2.setDependencies(singletonList(toDependency(projectModuleB)));
        projectParent.setCollectedProjects(asList(
                projectIndependentModule,
                projectModuleA,

        for (TaskSegment taskSegment : taskSegments) {
            List<MavenProject> projects;

            if (taskSegment.isAggregating()) {
                projects = Collections.singletonList(rootProject);
            } else {
                projects = session.getProjects();
            }
            for (MavenProject project : projects) {

        InternalSession.associate(rsession, session);

        List<ProjectBuildingResult> results = projectBuilder.build(
                Collections.singletonList(new File("src/test/resources/projects/tree/pom.xml")), true, request);

        assertEquals(3, results.size());
    }

                    .filter(projectAndSubmodules::contains)
                    .collect(Collectors.toList()); // sorted and filtered to what we need
        } else {
            return Collections.singletonList(project);
        }
    }

    public void resolveProjectDependencies(
            MavenProject project,
            Collection<String> scopesToCollect,
            Collection<String> scopesToResolve,

    assertEquals(Collections.emptyList(), list);
  }

  public void testCreation_oneElement() {
    List<String> list = ImmutableList.of("a");
    assertEquals(Collections.singletonList("a"), list);
  }

  public void testCreation_twoElements() {
    List<String> list = ImmutableList.of("a", "b");
    assertEquals(Lists.newArrayList("a", "b"), list);
  }

            new TestStringListGenerator() {
              @Override
              public List<String> create(String[] elements) {
                return Collections.singletonList(elements[0]);
              }
            })
        .named("singletonList")
        .withFeatures(
            CollectionFeature.SERIALIZABLE,
            CollectionFeature.ALLOWS_NULL_VALUES,
            CollectionSize.ONE)

    Iterator<String> set = asList("a", "b").iterator();
    assertFalse(Iterators.contains(set, null));
  }

  public void testGetOnlyElement_noDefault_valid() {
    Iterator<String> iterator = Collections.singletonList("foo").iterator();
    assertEquals("foo", Iterators.getOnlyElement(iterator));
  }

  public void testGetOnlyElement_noDefault_empty() {
    Iterator<String> iterator = Iterators.emptyIterator();
    try {

        for (String goal : goals) {
            PluginExecution pluginExecution = new PluginExecution();
            pluginExecution.setId("default-" + goal);
            pluginExecution.setGoals(Collections.singletonList(goal));
            plugin.addExecution(pluginExecution);
        }

        return plugin;
    }

    public void calculateForkedExecutions(MojoExecution mojoExecution, MavenSession session) {}

     *          {@code artifact} is {@code null}.
     */
    default void install(Session session, Artifact artifact) {
        install(session, Collections.singletonList(artifact));
    }

    /**
     * @param session the repository session
     * @param artifacts Collection of {@link Artifact MavenArtifacts}

        lifecycle.setId("default");
        lifecycle.setLifecyclePhases(Collections.unmodifiableMap(lifecyclePhaseBindings));

        this.lifecycleMapping = new DefaultLifecycleMapping(Collections.singletonList(lifecycle));
    }

    @Override
    public LifecycleMapping get() {
        return lifecycleMapping;
    }