if (hasLowerBound && hasUpperBound) {
      int cmp =
          comparator.compare(
              uncheckedCastNullableTToT(lowerEndpoint), uncheckedCastNullableTToT(upperEndpoint));
      // be consistent with Range
      checkArgument(
          cmp <= 0, "lowerEndpoint (%s) > upperEndpoint (%s)", lowerEndpoint, upperEndpoint);
      if (cmp == 0) {
        checkArgument(lowerBoundType != OPEN || upperBoundType != OPEN);
      }
    }

    if (hasLowerBound && hasUpperBound) {
      int cmp =
          comparator.compare(
              uncheckedCastNullableTToT(lowerEndpoint), uncheckedCastNullableTToT(upperEndpoint));
      // be consistent with Range
      checkArgument(
          cmp <= 0, "lowerEndpoint (%s) > upperEndpoint (%s)", lowerEndpoint, upperEndpoint);
      if (cmp == 0) {
        checkArgument(lowerBoundType != OPEN || upperBoundType != OPEN);
      }
    }

@NullMarked
public class RangeTest extends TestCase {
  public void testOpen() {
    Range<Integer> range = Range.open(4, 8);
    checkContains(range);
    assertTrue(range.hasLowerBound());
    assertEquals(4, (int) range.lowerEndpoint());
    assertEquals(OPEN, range.lowerBoundType());
    assertTrue(range.hasUpperBound());
    assertEquals(8, (int) range.upperEndpoint());
    assertEquals(OPEN, range.upperBoundType());
    assertFalse(range.isEmpty());

@NullMarked
public class RangeTest extends TestCase {
  public void testOpen() {
    Range<Integer> range = Range.open(4, 8);
    checkContains(range);
    assertTrue(range.hasLowerBound());
    assertEquals(4, (int) range.lowerEndpoint());
    assertEquals(OPEN, range.lowerBoundType());
    assertTrue(range.hasUpperBound());
    assertEquals(8, (int) range.upperEndpoint());
    assertEquals(OPEN, range.upperBoundType());
    assertFalse(range.isEmpty());

    } else if (b.isEmpty()) {
      assertThat(rangeSet.asRanges()).contains(a);
    } else if (a.isConnected(b)) {
      assertThat(rangeSet.asRanges()).containsExactly(a.span(b));
    } else {
      if (a.lowerEndpoint() < b.lowerEndpoint()) {
        assertThat(rangeSet.asRanges()).containsExactly(a, b).inOrder();
      } else {
        assertThat(rangeSet.asRanges()).containsExactly(b, a).inOrder();
      }
    }
  }

  /**
   * Returns the lower endpoint of this range.
   *
   * @throws IllegalStateException if this range is unbounded below (that is, {@link
   *     #hasLowerBound()} returns {@code false})
   */
  public C lowerEndpoint() {
    return lowerBound.endpoint();
  }

  /**
   * Returns the type of this range's lower bound: {@link BoundType#CLOSED} if the range includes
   * its lower endpoint, {@link BoundType#OPEN} if it does not.