assertSame(copy, copy.iterator().next());
  }

  @J2ktIncompatible
  @GwtIncompatible // Only used by @GwtIncompatible code
  private static class MultisetHolder implements Serializable {
    private final Multiset<?> member;

    MultisetHolder(Multiset<?> multiset) {
      this.member = multiset;
    }

    @GwtIncompatible @J2ktIncompatible private static final long serialVersionUID = 1L;
  }

    assertThrows(NullPointerException.class, () -> Functions.toStringFunction().apply(null));
  }

  @J2ktIncompatible
  @GwtIncompatible // SerializableTester
  public void testToStringFunctionSerializable() {
    checkCanReserializeSingleton(Functions.toStringFunction());
  }

  @J2ktIncompatible
  @GwtIncompatible // NullPointerTester
  public void testNullPointerExceptions() {
    NullPointerTester tester = new NullPointerTester();

   * that it can be GWTified?
   */
  @CanIgnoreReturnValue
  @GwtIncompatible // SerializableTester
  static <E> Set<E> reserializeAndAssertLenient(Set<E> original) {
    Set<E> copy = reserialize(original);
    assertEquals(original, copy);
    assertTrue(copy instanceof ImmutableSet);
    return copy;
  }

  @CanIgnoreReturnValue
  @GwtIncompatible // SerializableTester

@SuppressWarnings("SetAutoIncrementStep_Nanos")
@NullUnmarked
public class FakeTickerTest extends TestCase {

  @GwtIncompatible // NullPointerTester
  public void testNullPointerExceptions() {
    NullPointerTester tester = new NullPointerTester();
    tester.testAllPublicInstanceMethods(new FakeTicker());
  }

  @GwtIncompatible // java.time.Duration
  @IgnoreJRERequirement // TODO: b/288085449 - Remove this once we use library-desugaring scents.

import static com.google.common.collect.Internal.toNanosSaturated;
import static java.util.concurrent.TimeUnit.NANOSECONDS;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.common.base.Preconditions;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.time.Duration;
import java.util.ArrayDeque;

import static java.nio.charset.StandardCharsets.UTF_8;
import static java.util.Objects.requireNonNull;
import static java.util.concurrent.TimeUnit.SECONDS;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.common.base.CharMatcher;
import com.google.common.base.Defaults;
import com.google.common.base.Equivalence;
import com.google.common.base.Joiner;

        new ArrayList<>(SerializableTester.reserialize(map.values())));
  }

  @GwtIncompatible // SerializableTester
  public void testEmpty_serialization() {
    SortedSet<String> set = new SafeTreeSet<>();
    SortedSet<String> copy = SerializableTester.reserializeAndAssert(set);
    assertEquals(set.comparator(), copy.comparator());
  }

  @GwtIncompatible // SerializableTester
  public void testSingle_serialization() {

/**
 * Outer class that exists solely to let us write {@code Partially.GwtIncompatible} instead of plain
 * {@code GwtIncompatible}. This is more accurate for {@link Futures#catching}, which is available
 * under GWT but with a slightly different signature.
 *
 * <p>We can't use {@code PartiallyGwtIncompatible} because then the GWT compiler wouldn't recognize
 * it as a {@code GwtIncompatible} annotation. And for {@code Futures.catching}, we need the GWT

@SuppressWarnings("SetAutoIncrementStep_Nanos")
@NullUnmarked
public class FakeTickerTest extends TestCase {

  @GwtIncompatible // NullPointerTester
  public void testNullPointerExceptions() {
    NullPointerTester tester = new NullPointerTester();
    tester.testAllPublicInstanceMethods(new FakeTicker());
  }

  @GwtIncompatible // java.time.Duration
  public void testAdvance() {
    FakeTicker ticker = new FakeTicker();

        reserializeAndAssert(builder.build());
      }
    }
  }

  @GwtIncompatible
  @J2ktIncompatible
    private static void reserializeAndAssert(Object object) throws Exception {
    Object copy = reserialize(object);
    assertEquals(object, copy);
    assertEquals(object.getClass(), copy.getClass());
  }

  @GwtIncompatible
  @J2ktIncompatible