import junit.framework.TestCase;
import junit.framework.TestSuite;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Unit test for {@code Iterators}.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@NullMarked
public class IteratorsTest extends TestCase {

  @J2ktIncompatible
  @GwtIncompatible // suite
  @AndroidIncompatible // test-suite builders
  public static Test suite() {

 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/ImmutableCollectionsExplained">immutable collections</a>.
 *
 * @author Jesse Wilson
 * @author Kevin Bourrillion
 * @since 2.0
 */
@DoNotMock("Use ImmutableMap.of or another implementation")
@GwtCompatible
@SuppressWarnings("serial") // we're overriding default serialization

 * absolutely necessary.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/CollectionUtilitiesExplained#iterables">{@code
 * Iterables}</a>.
 *
 * @author Kevin Bourrillion
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible
public final class Iterables {
  private Iterables() {}

  /** Returns an unmodifiable view of {@code iterable}. */

 *
 * <h3>More information</h3>
 *
 * <p>See the Guava User Guide on <a
 * href="https://github.com/google/guava/wiki/PreconditionsExplained">using {@code
 * Preconditions}</a>.
 *
 * @author Kevin Bourrillion
 * @since 2.0
 */
@GwtCompatible
public final class Preconditions {
  private Preconditions() {}

  /**
   * Ensures the truth of an expression involving one or more parameters to the calling method.

 * {@link Lists}, {@link Maps} and {@link Queues}.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/CollectionUtilitiesExplained#sets">{@code Sets}</a>.
 *
 * @author Kevin Bourrillion
 * @author Jared Levy
 * @author Chris Povirk
 * @since 2.0
 */
@GwtCompatible
public final class Sets {
  private Sets() {}

  /**

 *
 * <p>See the Guava User Guide article on <a
 * href="https://github.com/google/guava/wiki/StringsExplained#charmatcher">{@code CharMatcher}
 * </a>.
 *
 * @author Kevin Bourrillion
 * @since 1.0
 */
@GwtCompatible
public abstract class CharMatcher implements Predicate<Character> {
  /*
   *           N777777777NO
   *         N7777777777777N
   *        M777777777777777N

 * necessary.
 *
 * <p>See the Guava User Guide section on <a href=
 * "https://github.com/google/guava/wiki/CollectionUtilitiesExplained#iterables">{@code
 * Iterators}</a>.
 *
 * @author Kevin Bourrillion
 * @author Jared Levy
 * @since 2.0
 */
@GwtCompatible
public final class Iterators {
  private Iterators() {}

  /**
   * Returns the empty iterator.
   *