E duplicate = arrayAndDuplicate.duplicate;

    int firstIndex = getList().indexOf(duplicate);
    int initialSize = getList().size();
    assertTrue("remove(present) should return true", getList().remove(duplicate));
    assertTrue(
        "After remove(duplicate), a list should still contain the duplicate element",
        getList().contains(duplicate));
    assertFalse(

  public void testRemoveAtIndex_unsupported() {
    assertThrows(UnsupportedOperationException.class, () -> getList().remove(0));
    expectUnchanged();
  }

  @ListFeature.Require(SUPPORTS_REMOVE_WITH_INDEX)
  public void testRemoveAtIndex_negative() {
    assertThrows(IndexOutOfBoundsException.class, () -> getList().remove(-1));
    expectUnchanged();
  }

  @ListFeature.Require(SUPPORTS_REMOVE_WITH_INDEX)

    int index = aValidIndex();
    E initialValue = getList().get(index);
    assertEquals(
        "set(i, x) should return the old element at position i.",
        initialValue,
        getList().set(index, newValue));
    assertEquals("After set(i, x), get(i) should return x", newValue, getList().get(index));
    assertEquals("set() should not change the size of a list.", getNumElements(), getList().size());
  }

    assertFalse(
        "Sets of different sizes should not be equal.",
        getSet().equals(MinimalSet.from(moreElements)));
  }

  public void testEquals_list() {
    assertFalse("A List should never equal a Set.", getSet().equals(copyToList(getSet())));
  }

    assertFalse(
        "Sets of different sizes should not be equal.",
        getSet().equals(MinimalSet.from(moreElements)));
  }

  public void testEquals_list() {
    assertFalse("A List should never equal a Set.", getSet().equals(copyToList(getSet())));
  }

    assertFalse(
        "Lists of different sizes should not be equal.",
        getList().equals(new ArrayList<E>(moreElements)));
  }

  public void testEquals_set() {
    assertFalse("A List should never equal a Set.", getList().equals(MinimalSet.from(getList())));
  }

    Set<Object> observed = Sets.newIdentityHashSet(); // for the sake of weakly referenced locks.
    // this gets the stripes with #getAt(index)
    for (int i = 0; i < striped.size(); i++) {
      Object object = striped.getAt(i);
      assertNotNull(object);
      assertSame(object, striped.getAt(i)); // idempotent
      observed.add(object);
    }
    assertTrue("All stripes observed", observed.size() == striped.size());

    Set<Object> observed = Sets.newIdentityHashSet(); // for the sake of weakly referenced locks.
    // this gets the stripes with #getAt(index)
    for (int i = 0; i < striped.size(); i++) {
      Object object = striped.getAt(i);
      assertNotNull(object);
      assertSame(object, striped.getAt(i)); // idempotent
      observed.add(object);
    }
    assertTrue("All stripes observed", observed.size() == striped.size());

    private static class OptionComparator implements Comparator<Option> {
        public int compare(Option opt1, Option opt2) {
            String s1 = opt1.getOpt() != null ? opt1.getOpt() : opt1.getLongOpt();
            String s2 = opt2.getOpt() != null ? opt2.getOpt() : opt2.getLongOpt();
            return s1.compareToIgnoreCase(s2);
        }
    }

    private static class CLIManagerExtension extends CLIManager {

  public void testToArray_noArg() {
    Object[] actual = getList().toArray();
    assertArrayEquals("toArray() order should match list", createOrderedArray(), actual);
  }

  @CollectionSize.Require(absent = ZERO)
  public void testToArray_tooSmall() {
    Object[] actual = getList().toArray(new Object[0]);