* Collections.unmodifiableList}'s iterator:
 *
 * {@snippet :
 * List<String> expectedElements =
 *     Arrays.asList("a", "b", "c", "d", "e");
 * List<String> actualElements =
 *     Collections.unmodifiableList(
 *         Arrays.asList("a", "b", "c", "d", "e"));
 * IteratorTester<String> iteratorTester =
 *     new IteratorTester<String>(
 *         6,
 *         IteratorFeature.UNMODIFIABLE,

  public void testConcatUnmodifiable() {
    new IteratorTester<Integer>(
        5, UNMODIFIABLE, asList(1, 2), IteratorTester.KnownOrder.KNOWN_ORDER) {
      @Override
      protected Iterator<Integer> newTargetIterator() {
        return Iterators.concat(
            asList(1).iterator(), Arrays.<Integer>asList().iterator(), asList(2).iterator());
      }
    }.test();
  }

  public void testConcatPartiallyAdvancedSecond() {

  }

  public void testIsOrdered() {
    assertFalse(numberOrdering.isOrdered(asList(5, 3, 0, 9)));
    assertFalse(numberOrdering.isOrdered(asList(0, 5, 3, 9)));
    assertTrue(numberOrdering.isOrdered(asList(0, 3, 5, 9)));
    assertTrue(numberOrdering.isOrdered(asList(0, 0, 3, 3)));
    assertTrue(numberOrdering.isOrdered(asList(0, 3)));
    assertTrue(numberOrdering.isOrdered(singleton(1)));

  }

  public void testIsOrdered() {
    assertFalse(numberOrdering.isOrdered(asList(5, 3, 0, 9)));
    assertFalse(numberOrdering.isOrdered(asList(0, 5, 3, 9)));
    assertTrue(numberOrdering.isOrdered(asList(0, 3, 5, 9)));
    assertTrue(numberOrdering.isOrdered(asList(0, 0, 3, 3)));
    assertTrue(numberOrdering.isOrdered(asList(0, 3)));
    assertTrue(numberOrdering.isOrdered(singleton(1)));

        .testEquals();
  }

  public void testIsInOrder() {
    assertFalse(isInOrder(asList(5, 3, 0, 9), Ordering.natural()));
    assertFalse(isInOrder(asList(0, 5, 3, 9), Ordering.natural()));
    assertTrue(isInOrder(asList(0, 3, 5, 9), Ordering.natural()));
    assertTrue(isInOrder(asList(0, 0, 3, 3), Ordering.natural()));
    assertTrue(isInOrder(asList(0, 3), Ordering.natural()));
    assertTrue(isInOrder(singleton(1), Ordering.natural()));

      assertThat(keys.remove(null)).isFalse();
      assertThat(keys.remove(6)).isFalse();
      assertThat(keys.remove(-6)).isFalse();
      assertThat(keys.removeAll(asList(null, 0, 15, 1500))).isFalse();
      assertThat(keys.retainAll(asList(null, 0, 15, 1500))).isFalse();
      checkEmpty(keys);
      checkEmpty(cache);
    }
  }

  public void testKeySet_remove() {

      assertThat(keys.remove(null)).isFalse();
      assertThat(keys.remove(6)).isFalse();
      assertThat(keys.remove(-6)).isFalse();
      assertThat(keys.removeAll(asList(null, 0, 15, 1500))).isFalse();
      assertThat(keys.retainAll(asList(null, 0, 15, 1500))).isFalse();
      checkEmpty(keys);
      checkEmpty(cache);
    }
  }

  public void testKeySet_remove() {

        assertNotNull(second);
        // Due to round-robin, should get different channels or same order
        assertTrue(Arrays.asList(channel1, channel2).contains(first));
        assertTrue(Arrays.asList(channel1, channel2).contains(second));
    }

    @Test
    void testLeastLoadedStrategy() {
        loadBalancer.setStrategy(LoadBalancingStrategy.LEAST_LOADED);

    Iterable<?> b;

    // A few elements.
    a = asList(4, 8, 15, 16, 23, 42);
    b = asList(4, 8, 15, 16, 23, 42);
    assertTrue(elementsEqual(a, b));

    // An element differs.
    a = asList(4, 8, 15, 12, 23, 42);
    b = asList(4, 8, 15, 16, 23, 42);
    assertFalse(elementsEqual(a, b));

    // null versus non-null.
    a = Arrays.<@Nullable Integer>asList(4, 8, 15, null, 23, 42);

import static com.google.common.collect.testing.Helpers.getMethod;
import static com.google.common.collect.testing.features.FeatureUtil.addImpliedFeatures;
import static java.util.Arrays.asList;
import static java.util.Collections.disjoint;
import static java.util.Collections.unmodifiableSet;
import static java.util.logging.Level.FINER;

import com.google.common.annotations.GwtIncompatible;