}

    @Override
    public boolean removeAll(final Collection<?> collection) {
      return removeIf(collection::contains);
    }

    @Override
    public boolean retainAll(final Collection<?> collection) {
      return removeIf(element -> !collection.contains(element));
    }

    @Override

    assertEquals(Collections.singleton("a"), set);
  }

  public void testCopyOf_collection_oneElementRepeated() {
    Collection<String> c = MinimalCollection.of("a", "a", "a");
    Set<String> set = copyOf(c);
    assertEquals(Collections.singleton("a"), set);
  }

  public void testCopyOf_collection_general() {
    Collection<String> c = MinimalCollection.of("a", "b", "a");
    Set<String> set = copyOf(c);

    assertEquals(Collections.singleton("a"), set);
  }

  public void testCopyOf_collection_oneElementRepeated() {
    Collection<String> c = MinimalCollection.of("a", "a", "a");
    Set<String> set = copyOf(c);
    assertEquals(Collections.singleton("a"), set);
  }

  public void testCopyOf_collection_general() {
    Collection<String> c = MinimalCollection.of("a", "b", "a");
    Set<String> set = copyOf(c);

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.common.annotations.VisibleForTesting;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.Set;
import javax.annotation.CheckForNull;

  public void testRowComparator() {
    sortedTable = TreeBasedTable.create();
    assertSame(Ordering.natural(), sortedTable.rowComparator());

    sortedTable = TreeBasedTable.create(Collections.reverseOrder(), Ordering.usingToString());
    assertSame(Collections.reverseOrder(), sortedTable.rowComparator());
  }

  public void testColumnComparator() {
    sortedTable = TreeBasedTable.create();
    sortedTable.put("", 42, 'x');

    assertTrue(multimap.get("a") instanceof ImmutableSortedSet);
    assertEquals(
        Collections.reverseOrder(), ((ImmutableSortedSet<Integer>) multimap.get("a")).comparator());
    assertTrue(multimap.get("x") instanceof ImmutableSortedSet);
    assertEquals(
        Collections.reverseOrder(), ((ImmutableSortedSet<Integer>) multimap.get("x")).comparator());

 * limitations under the License.
 */

package com.google.common.collect.testing;

import static java.util.Collections.singleton;

import com.google.common.annotations.GwtCompatible;
import com.google.common.annotations.J2ktIncompatible;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.collect;

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

/**
 * GWT implementation of {@link ImmutableSet} that forwards to another {@code Set} implementation.
 *

  public void testToArrayEmpty() {
    Iterator<String> iterator = Collections.<String>emptyList().iterator();
    String[] array = Iterators.toArray(iterator, String.class);
    assertTrue(Arrays.equals(new String[0], array));
  }

  @GwtIncompatible // Iterators.toArray(Iterator, Class)
  public void testToArraySingleton() {
    Iterator<String> iterator = Collections.singletonList("a").iterator();

import java.util.function.Function;
import java.util.stream.Collector;
import java.util.stream.Collectors;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * GWT emulation of {@link com.google.common.collect.ImmutableMap}. For non sorted maps, it is a
 * thin wrapper around {@link java.util.Collections#emptyMap()}, {@link
 * Collections#singletonMap(Object, Object)} and {@link java.util.LinkedHashMap} for empty,