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 {

    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 {

        private List<ProjectBuildingResult> doBuild(Map<File, MavenProject> projectIndex, InterimResult interimResult) {
            if (interimResult.projectBuildingResult != null) {
                return Collections.singletonList(interimResult.projectBuildingResult);
            }
            MavenProject project = interimResult.project;
            try {