### Question:
DependencyGraph { public List<DependencyPath> list() { return new ArrayList<>(graph); } DependencyGraph(DependencyNode root); void addPath(DependencyPath path); List<DependencyPath> list(); DependencyPath getRootPath(); List<DependencyPath> getChildren(DependencyPath parent); Set<DependencyPath> getPaths(String coordinates); List<Update> findUpdates(); Map<String, String> getHighestVersionMap(); Set<UnresolvableArtifactProblem> getUnresolvedArtifacts(); UnresolvableArtifactProblem createUnresolvableArtifactProblem(Artifact artifact); static DependencyGraph from(DependencyNode root);  }### Answer:
@Test public void testAdd() { List<DependencyPath> all = graph.list(); Truth.assertThat(all).containsExactly(path1, path2, path3, path4, path5, path6).inOrder(); }