* @return an array containing the same values as {@code collection}, in the same order, converted
   *     to primitives
   * @throws NullPointerException if {@code collection} or any of its elements is null
   */
  public static boolean[] toArray(Collection<Boolean> collection) {
    if (collection instanceof BooleanArrayAsList) {
      return ((BooleanArrayAsList) collection).toBooleanArray();
    }

   * @return an array containing the same values as {@code collection}, in the same order, converted
   *     to primitives
   * @throws NullPointerException if {@code collection} or any of its elements is null
   */
  public static boolean[] toArray(Collection<Boolean> collection) {
    if (collection instanceof BooleanArrayAsList) {
      return ((BooleanArrayAsList) collection).toBooleanArray();
    }

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.features.CollectionSize;
import java.util.Collection;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * The subject-generator interface accepted by Collection testers, for testing a Collection at one
 * particular {@link CollectionSize}.
 *
 * <p>This interface should not be implemented outside this package; {@link

  }

  @Override
  protected Collection<Method> suppressForConcurrentSkipListMap() {
    List<Method> methods = new ArrayList<>();
    methods.addAll(super.suppressForConcurrentSkipListMap());
    methods.add(getContainsEntryWithIncomparableKeyMethod());
    methods.add(getContainsEntryWithIncomparableValueMethod());
    return methods;
  }

  @Override
  protected Collection<Method> suppressForHashtable() {

  public final <C extends Collection<? super E>> C copyInto(C collection) {
    checkNotNull(collection);
    Iterable<E> iterable = getDelegate();
    if (iterable instanceof Collection) {
      collection.addAll((Collection<E>) iterable);
    } else {
      for (E item : iterable) {
        collection.add(item);
      }
    }
    return collection;
  }

  /**

  }

  private boolean runCollectionTests = true;

  /**
   * Specify whether to skip the general collection tests. Call this method when testing a
   * collection that's both a queue and a list, to avoid running the common collection tests twice.
   * By default, collection tests do run.
   */
  @CanIgnoreReturnValue
  public QueueTestSuiteBuilder<E> skipCollectionTests() {
    runCollectionTests = false;

  }

  private void assertCollectionSize(Collection<?> collection, int size) {
    assertEquals(size, collection.size());
    if (size > 0) {
      assertFalse(collection.isEmpty());
    } else {
      assertTrue(collection.isEmpty());
    }
    assertEquals(size, Iterables.size(collection));
    assertEquals(size, Iterators.size(collection.iterator()));
  }

  }

  private void assertCollectionSize(Collection<?> collection, int size) {
    assertEquals(size, collection.size());
    if (size > 0) {
      assertFalse(collection.isEmpty());
    } else {
      assertTrue(collection.isEmpty());
    }
    assertEquals(size, Iterables.size(collection));
    assertEquals(size, Iterators.size(collection.iterator()));
  }

import java.util.Collection;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

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

 */

package com.google.common.collect.testing;

import com.google.common.annotations.GwtCompatible;

/**
 * A type which will never be used as the element type of any collection in our tests, and so can be
 * used to test how a Collection behaves when given input of the wrong type.
 */
@GwtCompatible
public enum WrongType {
  VALUE