} catch (AssertionFailedError expected) {
      for (String message : expectedMessages) {
        assertThat(expected.getMessage()).contains(message);
      }
      return;
    }
    fail("expected failure not reported");
  }

  private class ForwardingRunnable implements Runnable {

    private final Runnable runnable;

    ForwardingRunnable(Runnable runnable) {
      this.runnable = runnable;
    }

 *
 * <p>The one downside of {@code Stopwatch} relative to {@link System#nanoTime()} is that {@code
 * Stopwatch} requires object allocation and additional method calls, which can reduce the accuracy
 * of the elapsed times reported. {@code Stopwatch} is still suitable for logging and metrics where
 * reasonably accurate values are sufficient. If the uncommon case that you need to maximize
 * accuracy, use {@code System.nanoTime()} directly instead.
 *

  /**
   * If true, report on stdout all "slow" tests, that is, ones that take more than profileThreshold
   * milliseconds to execute.
   */
  private static final boolean profileTests = Boolean.getBoolean("jsr166.profileTests");

  /**
   * The number of milliseconds that tests are permitted for execution without being reported, when
   * profileTests is set.
   */

      ImmutableBiMap.copyOf(map);
      fail();
    } catch (IllegalArgumentException expected) {
      assertThat(expected.getMessage()).containsMatch("1|2");
      // We don't specify which of the two dups should be reported.
    }
  }

  // TODO(b/172823566): Use mainline testToImmutableBiMap once CollectorTester is usable to java7.
  public void testToImmutableBiMap_java7_combine() {
    ImmutableBiMap.Builder<String, Integer> zis =

  /**
   * If true, report on stdout all "slow" tests, that is, ones that take more than profileThreshold
   * milliseconds to execute.
   */
  private static final boolean profileTests = Boolean.getBoolean("jsr166.profileTests");

  /**
   * The number of milliseconds that tests are permitted for execution without being reported, when
   * profileTests is set.
   */

 *
 * <p>The one downside of {@code Stopwatch} relative to {@link System#nanoTime()} is that {@code
 * Stopwatch} requires object allocation and additional method calls, which can reduce the accuracy
 * of the elapsed times reported. {@code Stopwatch} is still suitable for logging and metrics where
 * reasonably accurate values are sufficient. If the uncommon case that you need to maximize
 * accuracy, use {@code System.nanoTime()} directly instead.
 *

    } catch (AssertionFailedError expected) {
      for (String message : expectedMessages) {
        assertThat(expected.getMessage()).contains(message);
      }
      return;
    }
    fail("expected failure not reported");
  }

  private class ForwardingRunnable implements Runnable {

    private final Runnable runnable;

    ForwardingRunnable(Runnable runnable) {
      this.runnable = runnable;
    }

    synchronized (collection) { // for Collections.synchronized
      assertFalse(collection.spliterator().hasCharacteristics(Spliterator.IMMUTABLE));
    }
  }

  @CollectionFeature.Require(SUPPORTS_REMOVE)
  public void testSpliteratorNotImmutable_CollectionAllowsRemove() {
    // If remove is supported, verify that IMMUTABLE is not reported.

    builder.put(k1, v1);
    return builder.build();
  }

  /**
   * Returns an immutable multimap containing the given entries, in order. Repeated occurrences of
   * an entry (according to {@link Object#equals}) after the first are ignored.
   */
  public static <K, V> ImmutableSetMultimap<K, V> of(K k1, V v1, K k2, V v2) {

import java.util.Collections;
import java.util.List;
import java.util.Random;
import java.util.RandomAccess;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/** Tests for repeated node and edge addition and removal in a {@link Graph}. */
@RunWith(JUnit4.class)

public final class GraphMutationTest {
  private static final int NUM_TRIALS = 50;
  private static final int NUM_NODES = 100;