@ParameterizedTest
  @ArgumentsSource(FileSystemParamProvider::class)
  fun iterator(parameters: Pair<FileSystem, Boolean>) {
    setUp(parameters.first, parameters.second)
    set("a", "a1", "a2")
    set("b", "b1", "b2")
    set("c", "c1", "c2")
    val iterator = cache.snapshots()
    assertThat(iterator.hasNext()).isTrue()
    iterator.next().use {
      assertThat(it.key()).isEqualTo("a")

import java.io.Reader;
import java.util.Iterator;
import org.jspecify.annotations.Nullable;

/**
 * A {@link Reader} that concatenates multiple readers.
 *
 * @author Bin Zhu
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
final class MultiReader extends Reader {
  private final Iterator<? extends CharSource> it;
  private @Nullable Reader current;

        return MutableClassToInstanceMap.this.delegate().entrySet();
      }

      @Override
      public Iterator<Entry<Class<? extends @NonNull B>, B>> iterator() {
        return new TransformedIterator<
            Entry<Class<? extends @NonNull B>, B>, Entry<Class<? extends @NonNull B>, B>>(
            delegate().iterator()) {
          @Override
          Entry<Class<? extends @NonNull B>, B> transform(

   *     have the same bit length
   */
  public static HashCode combineOrdered(Iterable<HashCode> hashCodes) {
    Iterator<HashCode> iterator = hashCodes.iterator();
    checkArgument(iterator.hasNext(), "Must be at least 1 hash code to combine.");
    int bits = iterator.next().bits();
    byte[] resultBytes = new byte[bits / 8];
    for (HashCode hashCode : hashCodes) {
      byte[] nextBytes = hashCode.asBytes();

      return standardToString();
    }

    @Override
    public Set<Entry<K, V>> entrySet() {
      return new StandardEntrySet() {
        @Override
        public Iterator<Entry<K, V>> iterator() {
          return backingMap.entrySet().iterator();
        }
      };
    }

    @Override
    public void clear() {
      standardClear();
    }

    @Override
    public boolean isEmpty() {

        tempFile.deleteOnExit();
        markForDeletion(tempFile);

        return tempFile;
    }

    public void cleanUp() throws IOException {
        for (Iterator it = filesToDelete.iterator(); it.hasNext(); ) {
            File file = (File) it.next();

            if (file.exists()) {
                if (file.isDirectory()) {
                    FileUtils.deleteDirectory(file);

    // having inconsistent iteration orderings.
    Map<Currency, Country> map =
        ImmutableMap.of(
            Currency.DOLLAR, Country.CANADA,
            Currency.PESO, Country.CHILE,
            Currency.FRANC, Country.SWITZERLAND);
    EnumBiMap<Currency, Country> bimap = EnumBiMap.create(map);

    Iterator<Currency> iter = bimap.keySet().iterator();
    assertEquals(Currency.DOLLAR, iter.next());

 * target iterators on demand. It also requires three additional constructor parameters: {@code
 * elementsToInsert}, the elements to be passed to {@code set()} and {@code add()} calls; {@code
 * features}, the features supported by the iterator; and {@code expectedElements}, the elements the
 * iterator should return in order.
 *

        // When
        mockIterator.close();

        // Then
        verify(mockIterator).close();
    }

    @Test
    @DisplayName("Should extend Iterator and AutoCloseable")
    void testInterfaceInheritance() {
        // Then
        assertTrue(java.util.Iterator.class.isAssignableFrom(CloseableIterator.class));
        assertTrue(AutoCloseable.class.isAssignableFrom(CloseableIterator.class));
    }

      @Override
      public UnmodifiableIterator<E> iterator() {
        Iterable<E> incidentEdges =
            (selfLoopCount == 0)
                ? Iterables.concat(inEdgeMap.keySet(), outEdgeMap.keySet())
                : Sets.union(inEdgeMap.keySet(), outEdgeMap.keySet());
        return Iterators.unmodifiableIterator(incidentEdges.iterator());
      }

      @Override
      public int size() {