* work during upgrades. However it is generally inadvisable for <i>libraries</i> (which get
 * included on users' CLASSPATHs, outside the library developers' control) to do so.
 *
 * @author Kevin Bourrillion
 */
@Retention(RetentionPolicy.CLASS)
@Target({
  ElementType.ANNOTATION_TYPE,
  ElementType.CONSTRUCTOR,
  ElementType.FIELD,
  ElementType.METHOD,
  ElementType.TYPE
})
@Documented

import java.util.Collections;
import java.util.Iterator;
import java.util.NoSuchElementException;
import junit.framework.TestCase;

/**
 * Unit test for {@link MinimalIterable}.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
public class MinimalIterableTest extends TestCase {

  public void testOf_empty() {
    Iterable<String> iterable = MinimalIterable.<String>of();

import java.util.Collection;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Creates collections, containing sample elements, to be tested.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TestCollectionGenerator<E extends @Nullable Object>

 * generally be avoided. Prefer {@link Interners#newWeakInterner} or another {@code Interner}
 * implementation even for {@code String} interning.
 *
 * @author Kevin Bourrillion
 * @since 3.0
 */
@DoNotMock("Use Interners.new*Interner")
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public interface Interner<E> {
  /**

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

/**
 * Implementation of {@link ImmutableSet} with exactly one element.
 *
 * @author Kevin Bourrillion
 * @author Nick Kralevich
 */
@GwtCompatible(serializable = true, emulated = true)
@SuppressWarnings("serial") // uses writeReplace(), not default serialization
@ElementTypesAreNonnullByDefault

 * that support Java 1.4 and before. Our library needs to do the bare minimum to accommodate such
 * types, though their use may still require an explicit type parameter and/or warning suppression.
 *
 * @author Kevin Bourrillion
 */
@SuppressWarnings({"ComparableType", "rawtypes"}) // https://github.com/google/guava/issues/989
@GwtCompatible
@ElementTypesAreNonnullByDefault
class LegacyComparable implements Comparable, Serializable {

import com.google.common.collect.testing.SampleElements.Enums;
import java.util.List;
import java.util.Set;

/**
 * An abstract TestSetGenerator for generating sets containing enum values.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public abstract class TestEnumSetGenerator implements TestSetGenerator<AnEnum> {
  @Override
  public SampleElements<AnEnum> samples() {

import com.google.common.annotations.GwtCompatible;
import com.google.common.primitives.Ints;
import javax.annotation.CheckForNull;

/**
 * Static methods for implementing hash-based collections.
 *
 * @author Kevin Bourrillion
 * @author Jesse Wilson
 * @author Austin Appleby
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
final class Hashing {
  private Hashing() {}

  /*

import com.google.common.annotations.J2ktIncompatible;
import com.google.common.testing.NullPointerTester;
import java.util.Set;
import junit.framework.TestCase;

/**
 * Unit test for {@link Primitives}.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible(emulated = true)
public class PrimitivesTest extends TestCase {
  public void testIsWrapperType() {
    assertThat(Primitives.isWrapperType(Void.class)).isTrue();

import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.DoNotMock;

/**
 * Any object which can accept registrations of {@link TearDown} instances.
 *
 * @author Kevin Bourrillion
 * @since 10.0
 */
@DoNotMock("Implement with a lambda")
@GwtCompatible
@ElementTypesAreNonnullByDefault
public interface TearDownAccepter {
  /**