import com.google.common.testing.EqualsTester;
import java.util.Set;
import org.junit.After;
import org.junit.Test;

/**
 * Abstract base class for testing undirected {@link Graph} implementations defined in this package.
 */
public abstract class AbstractStandardUndirectedGraphTest extends AbstractGraphTest {

  @After
  public void validateUndirectedEdges() {
    for (Integer node : graph.nodes()) {

   * space character.
   *
   * <p>Not that it is allowed, but not necessarily desirable to specify {@code %} as a safe
   * character. This has the effect of creating an escaper which has no well-defined inverse but it
   * can be useful when escaping additional characters.
   *
   * @param safeChars a non-null string specifying additional safe characters for this escaper (the

import static org.junit.Assert.assertThrows;
import static org.junit.Assert.assertTrue;

import java.util.Set;
import org.junit.Test;

/**
 * Abstract base class for testing directed {@link Graph} implementations defined in this package.
 */
public abstract class AbstractStandardDirectedGraphTest extends AbstractGraphTest {

  @Override
  @Test
  public void nodes_checkReturnedSetMutability() {

    NEXT_HIGHER {
      @Override
      public int resultIndex(int higherIndex) {
        return higherIndex;
      }
    },
    /**
     * Return {@code ~insertionIndex}, where {@code insertionIndex} is defined as the point at which
     * the key would be inserted into the list: the index of the next higher element in the list, or
     * {@code list.size()} if there is no such element.
     *

   * @since 13.0
   */
  void addListener(Listener listener, Executor executor);

  /**
   * The lifecycle states of a service.
   *
   * <p>The ordering of the {@link State} enum is defined such that if there is a state transition
   * from {@code A -> B} then {@code A.compareTo(B) < 0}. N.B. The converse is not true, i.e. if

   * first decrementing to zero, and then removing. putIfAbsent or replace could observe the
   * intermediate zero-state. Ways we could deal with this are:
   *
   * - Don't define any of the ConcurrentMap operations. This is the current state of affairs.
   *
   * - Define putIfAbsent and replace as treating zero and absent identically (as currently
   *   implemented below). This is a bit surprising with putIfAbsent, which really becomes

    }
    assertNull(map.get(unmappedKey));
  }

  public void testGetNull() {
    Map<K, V> map = makeEitherMap();
    if (allowsNullKeys) {
      if (allowsNullValues) {
        // TODO: decide what to test here.
      } else {
        assertEquals(map.containsKey(null), map.get(null) != null);
      }
    } else {
      try {
        map.get(null);
      } catch (NullPointerException optional) {

     * defined as:
     *
     * <pre>{@code
     * ((element == null) ? 0 : element.hashCode()) ^ count
     * }</pre>
     */
    @Override
    int hashCode();

    /**
     * Returns the canonical string representation of this entry, defined as follows. If the count

 *   <li>No stats are modified by operations invoked on the {@linkplain Cache#asMap asMap} view of
 *       the cache.
 * </ul>
 *
 * <p>A lookup is specifically defined as an invocation of one of the methods {@link
 * LoadingCache#get(Object)}, {@link LoadingCache#getUnchecked(Object)}, {@link Cache#get(Object,
 * Callable)}, or {@link LoadingCache#getAll(Iterable)}.
 *
 * @author Charles Fry

 *   <li>No stats are modified by operations invoked on the {@linkplain Cache#asMap asMap} view of
 *       the cache.
 * </ul>
 *
 * <p>A lookup is specifically defined as an invocation of one of the methods {@link
 * LoadingCache#get(Object)}, {@link LoadingCache#getUnchecked(Object)}, {@link Cache#get(Object,
 * Callable)}, or {@link LoadingCache#getAll(Iterable)}.
 *
 * @author Charles Fry