} 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.

 *
 * <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.
   */

    } 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;
    }

      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 =

 *
 * <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.
    }
  }

  public void testToImmutableBiMap() {
    Collector<Entry<String, Integer>, ?, ImmutableBiMap<String, Integer>> collector =
        ImmutableBiMap.toImmutableBiMap(Entry::getKey, Entry::getValue);

      /** The executor on which this Callable will be scheduled. */
      private final ScheduledExecutorService executor;

      /**
       * The service that is managing this callable. This is used so that failure can be reported
       * properly.
       */
      /*
       * This reference is part of a reference cycle, which is typically something we want to avoid