static final String ERROR_ADDED_SELF_LOOP = "Should not be allowed to add a self-loop edge.";

  /** Creates and returns an instance of the graph to be tested. */
  abstract Graph<Integer> createGraph();

  /**
   * A proxy method that adds the node {@code n} to the graph being tested. In case of Immutable
   * graph implementations, this method should replace {@link #graph} with a new graph that includes
   * this node.
   */

import com.google.common.annotations.GwtCompatible;
import java.util.Set;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates sets, containing sample elements, to be tested.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible
@NullMarked
public interface TestSetGenerator<E extends @Nullable Object> extends TestCollectionGenerator<E> {
  @Override
  Set<E> create(Object... elements);

import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;
import org.junit.Ignore;

/**
 * Base class for collection testers.
 *
 * @param <E> the element type of the collection to be tested.
 * @author Kevin Bourrillion
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

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

/**
 * Creates multimaps, containing sample elements, to be tested.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@NullMarked
public interface TestMultimapGenerator<
        K extends @Nullable Object, V extends @Nullable Object, M extends Multimap<K, V>>

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

/**
 * Creates multimaps, containing sample elements, to be tested.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@NullMarked
public interface TestMultimapGenerator<
        K extends @Nullable Object, V extends @Nullable Object, M extends Multimap<K, V>>

# Invalid escaping should trigger the regular host error handling.
http://%3g%78%63%30%2e%30%32%35%30%2E.01

# Something that isn't exactly an IP should get treated as a host and
# spaces escaped.
http://192.168.0.1\shello

# Fullwidth and escaped UTF-8 fullwidth should still be treated as IP.
# These are "0Xc0.0250.01" in fullwidth.
http://\uff10\uff38\uff43\uff10\uff0e\uff10\uff12\uff15\uff10\uff0e\uff10\uff11  s:http p:/ h:192.168.0.1

import com.google.common.collect.testing.TestCollectionGenerator;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates multisets, containing sample elements, to be tested.
 *
 * @author Jared Levy
 */
@GwtCompatible
@NullMarked
public interface TestMultisetGenerator<E extends @Nullable Object>
    extends TestCollectionGenerator<E> {
  @Override

    //                                                                           =========
    // keeping parsed request parameters, normal texts or uploaded files
    // keys are requested parameter names (treated as field name here)
    protected Map<String, Object> elementsAll; // lazy-loaded, then after not null
    protected Map<String, MultipartFormFile> elementsFile; // me too
    protected Map<String, String[]> elementsText; // me too

import com.google.common.annotations.GwtCompatible;
import java.util.SortedSet;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates sorted sets, containing sample elements, to be tested.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@NullMarked
public interface TestSortedSetGenerator<E extends @Nullable Object> extends TestSetGenerator<E> {
  @Override

import com.google.common.annotations.GwtCompatible;
import java.util.SortedSet;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Creates sorted sets, containing sample elements, to be tested.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@NullMarked
public interface TestSortedSetGenerator<E extends @Nullable Object> extends TestSetGenerator<E> {
  @Override