assertEquals(-1, Iterables.indexOf(list, Predicates.equalTo("jack")));
  }

  public void testIndexOf_withDuplicates() {
    List<String> list = Lists.newArrayList("mary", "bob", "bob", "bob", "sam");
    assertEquals(0, Iterables.indexOf(list, Predicates.equalTo("mary")));
    assertEquals(1, Iterables.indexOf(list, Predicates.equalTo("bob")));

 * Weak reference with a {@code finalizeReferent()} method which a background thread invokes after
 * the garbage collector reclaims the referent. This is a simpler alternative to using a {@link
 * ReferenceQueue}.
 *
 * @author Bob Lee
 * @since 2.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public abstract class FinalizableWeakReference<T> extends WeakReference<T>
    implements FinalizableReference {
  /**

 * Weak reference with a {@code finalizeReferent()} method which a background thread invokes after
 * the garbage collector reclaims the referent. This is a simpler alternative to using a {@link
 * ReferenceQueue}.
 *
 * @author Bob Lee
 * @since 2.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public abstract class FinalizableWeakReference<T> extends WeakReference<T>
    implements FinalizableReference {
  /**

    assertEquals(-1, Iterables.indexOf(list, Predicates.equalTo("jack")));
  }

  public void testIndexOf_withDuplicates() {
    List<String> list = Lists.newArrayList("mary", "bob", "bob", "bob", "sam");
    assertEquals(0, Iterables.indexOf(list, Predicates.equalTo("mary")));
    assertEquals(1, Iterables.indexOf(list, Predicates.equalTo("bob")));

    try {
      Optional.of(null);
      fail();
    } catch (NullPointerException expected) {
    }
  }

  public void testFromNullable() {
    Optional<String> optionalName = Optional.fromNullable("bob");
    assertEquals("bob", optionalName.get());
  }

  public void testFromNullable_null() {
    // not promised by spec, but easier to test
    assertSame(Optional.absent(), Optional.fromNullable(null));
  }

import com.google.errorprone.annotations.DoNotMock;

/**
 * Implemented by references that have code to run after garbage collection of their referents.
 *
 * @see FinalizableReferenceQueue
 * @author Bob Lee
 * @since 2.0
 */
@DoNotMock("Use an instance of one of the Finalizable*Reference classes")
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public interface FinalizableReference {
  /**

 * after the garbage collector reclaims the referent. This is a simpler alternative to using a
 * {@link ReferenceQueue}.
 *
 * <p>Unlike a normal phantom reference, this reference will be cleared automatically.
 *
 * @author Bob Lee
 * @since 2.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public abstract class FinalizablePhantomReference<T> extends PhantomReference<T>
    implements FinalizableReference {
  /**

 * Soft reference with a {@code finalizeReferent()} method which a background thread invokes after
 * the garbage collector reclaims the referent. This is a simpler alternative to using a {@link
 * ReferenceQueue}.
 *
 * @author Bob Lee
 * @since 2.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public abstract class FinalizableSoftReference<T> extends SoftReference<T>
    implements FinalizableReference {
  /**

 * after the garbage collector reclaims the referent. This is a simpler alternative to using a
 * {@link ReferenceQueue}.
 *
 * <p>Unlike a normal phantom reference, this reference will be cleared automatically.
 *
 * @author Bob Lee
 * @since 2.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public abstract class FinalizablePhantomReference<T> extends PhantomReference<T>
    implements FinalizableReference {
  /**

import java.io.Serializable;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Equivalence applied on functional result.
 *
 * @author Bob Lee
 * @since 10.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
final class FunctionalEquivalence<F, T> extends Equivalence<F> implements Serializable {

  private static final long serialVersionUID = 0;