}
        }

        private boolean hasFailures() {
            return !resolveFailures.isEmpty() || !provisioningFailures.isEmpty();
        }

        private String failureMessage() {
            StringBuilder sb = new StringBuilder();
            if (!resolveFailures.isEmpty()) {
                sb.append("Some toolchain resolvers had internal failures: ")

    assertThat(multiset).isEmpty();
  }

  public void testRemoveOccurrencesIterableEmpty() {
    Multiset<String> multiset = HashMultiset.create();
    Iterable<String> toRemove = Arrays.asList("a", "b", "a");
    assertFalse(Multisets.removeOccurrences(multiset, toRemove));
    assertTrue(multiset.isEmpty());
  }

  public void testRemoveOccurrencesMultisetEmpty() {

            Model target,
            List<? extends DependencyManagement> sources,
            ModelBuilderRequest request,
            ModelProblemCollector problems) {
        if (sources != null && !sources.isEmpty()) {
            Map<String, Dependency> dependencies = new LinkedHashMap<>();

            DependencyManagement depMgmt = target.getDependencyManagement();

            if (depMgmt != null) {

     *
     * So {@code (b : c).plus(a) == (a : b : c)}
     */
    @CheckReturnValue
    public abstract PersistentList<T> plus(T element);

    public abstract boolean isEmpty();

    private PersistentList() {}

    private static final PersistentList<Object> NIL = new PersistentList<Object>() {
        @Override
        public void forEach(Consumer<? super Object> consumer) {
        }

    @Override
    protected void merge(Metadata recessive) {
        List<Plugin> recessivePlugins = recessive.getPlugins();
        List<Plugin> plugins = metadata.getPlugins();
        if (!recessivePlugins.isEmpty() || !plugins.isEmpty()) {
            LinkedHashMap<String, Plugin> mergedPlugins = new LinkedHashMap<>();
            recessivePlugins.forEach(p -> mergedPlugins.put(p.getPrefix(), p));

    @Override
    public FileCollectionFingerprint read(Decoder decoder) throws IOException {
        Map<String, FileSystemLocationFingerprint> fingerprints = fingerprintMapSerializer.read(decoder);
        if (fingerprints.isEmpty()) {
            return FileCollectionFingerprint.EMPTY;
        }
        ImmutableMultimap<String, HashCode> rootHashes = readRootHashes(decoder);
        HashCode strategyConfigurationHash = hashCodeSerializer.read(decoder);

        StringBuilder sb = new StringBuilder();
        if (!inclusions.isEmpty()) {
            sb.append("(");
            sb.append(join(inclusions, " OR "));
            sb.append(")");
            if (!exclusions.isEmpty()) {
                sb.append(" AND ");
            }
        }
        if (!exclusions.isEmpty()) {
            sb.append("NOT (");
            sb.append(join(exclusions, " OR "));

    ) {
        if (!spec.getComponentFilter().isSatisfiedBy(componentId)) {
            return ResolvedArtifactSet.EMPTY;
        } else {

            if (spec.getSelectFromAllVariants() && !artifacts.isEmpty()) {
                // Variants with overridden artifacts cannot be reselected since
                // we do not know the "true" attributes of the requested artifact.
                return ResolvedArtifactSet.EMPTY;

      Entry<K, Collection<V>> entry = entryIterator.next();
      K key = entry.getKey();
      Collection<V> collection = filterCollection(entry.getValue(), new ValuePredicate(key));
      if (!collection.isEmpty()
          && predicate.apply(Maps.<K, Collection<V>>immutableEntry(key, collection))) {
        if (collection.size() == entry.getValue().size()) {
          entryIterator.remove();
        } else {

                && profile.getDistributionManagement() == null
                && profile.getModules().isEmpty()
                && profile.getProperties().isEmpty()
                && profile.getRepositories().isEmpty()
                && profile.getPluginRepositories().isEmpty()
                && profile.getReporting() == null;
    }