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

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

            // we do a first pass by reading all rawModels in order.
            List<ProjectBuildingResult> results = new ArrayList<>();
            boolean failure = false;
            for (InterimResult r : interimResults) {
                DefaultProjectBuildingResult res;
                try {
                    Model model = modelBuilder.buildRawModel(r.request);

        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 {

   *   // Must be in the synchronized block
   *   Iterator<E> it = set2.descendingIterator();
   *   while (it.hasNext())
   *     foo(it.next());
   *   }
   * }
   * }</pre>
   *
   * <p>Failure to follow this advice may result in non-deterministic behavior.
   *
   * <p>The returned navigable set will be serializable if the specified navigable set is
   * serializable.
   *

        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()) {

   *   Iterator<Long> it = set.iterator(); // Must be in synchronized block
   *   while (it.hasNext()) {
   *     foo(it.next());
   *   }
   * }
   * }</pre>
   *
   * <p>Failure to follow this advice may result in non-deterministic behavior.
   *
   * <p>The returned bimap will be serializable if the specified bimap is serializable.
   *

    return (result == null) ? keySet = createKeySet() : result;
  }

  /*
   * This could have a good default implementation of return new ImmutableKeySet<K, V>(this),
   * but ProGuard can't figure out how to eliminate that default when RegularImmutableMap
   * overrides it.
   */
  abstract ImmutableSet<K> createKeySet();

  UnmodifiableIterator<K> keyIterator() {

   *   Iterator<V> i = values.iterator(); // Must be in synchronized block
   *   while (i.hasNext()) {
   *     foo(i.next());
   *   }
   * }
   * }</pre>
   *
   * <p>Failure to follow this advice may result in non-deterministic behavior.
   *
   * <p>Note that the generated multimap's {@link Multimap#removeAll} and {@link

@IgnoreJRERequirement // Users will use this only if they're already using streams.
@Beta // TODO: b/288085449 - Remove.
public final class MoreCollectors {

  /*
   * TODO(lowasser): figure out if we can convert this to a concurrent AtomicReference-based
   * collector without breaking j2cl?
   */
  private static final Collector<Object, ?, Optional<Object>> TO_OPTIONAL =
      Collector.of(

    return (UnmodifiableListIterator<T>) ArrayItr.EMPTY;
  }

  /**
   * This is an enum singleton rather than an anonymous class so ProGuard can figure out it's only
   * referenced by emptyModifiableIterator().
   */
  private enum EmptyModifiableIterator implements Iterator<Object> {
    INSTANCE;

    @Override
    public boolean hasNext() {