if (set.isEmpty()) {
        /*
         * The (tooLow + 1, tooHigh) arguments below would be invalid because tooLow would be
         * greater than tooHigh.
         */
        return ContiguousSet.create(Range.openClosed(0, 1), DiscreteDomain.integers()).subSet(0, 1);
      }
      int tooHigh = set.last() + 1;
      int tooLow = set.first() - 1;
      set.add(tooHigh);
      set.add(tooLow);

      if (set.isEmpty()) {
        /*
         * The (tooLow + 1, tooHigh) arguments below would be invalid because tooLow would be
         * greater than tooHigh.
         */
        return ContiguousSet.create(Range.openClosed(0, 1), DiscreteDomain.integers()).subSet(0, 1);
      }
      int tooHigh = set.last() + 1;
      int tooLow = set.first() - 1;
      set.add(tooHigh);
      set.add(tooLow);

            range.contains(i));
        assertEquals(
            ORDERING.compare(i, 3) < 0 || (ORDERING.compare(i, 3) == 0 && lBoundType == OPEN),
            range.tooLow(i));
        assertFalse(range.tooHigh(i));
      }
    }
  }

  public void testUpperRange() {
    for (BoundType lBoundType : BoundType.values()) {
      GeneralRange<@Nullable Integer> range = GeneralRange.upTo(ORDERING, 3, lBoundType);

            range.contains(i));
        assertEquals(
            ORDERING.compare(i, 3) < 0 || (ORDERING.compare(i, 3) == 0 && lBoundType == OPEN),
            range.tooLow(i));
        assertFalse(range.tooHigh(i));
      }
    }
  }

  public void testUpperRange() {
    for (BoundType lBoundType : BoundType.values()) {
      GeneralRange<@Nullable Integer> range = GeneralRange.upTo(ORDERING, 3, lBoundType);

      @Nullable Entry<E> prevEntry;

      @Override
      public boolean hasNext() {
        if (current == null) {
          return false;
        } else if (range.tooHigh(current.getElement())) {
          current = null;
          return false;
        } else {
          return true;
        }
      }

      @Override
      public Entry<E> next() {

    // Using a try/catch seems lazy, but the catch block will rarely get invoked (except for
    // durations longer than approximately +/- 292 years).
    try {
      return duration.toNanos();
    } catch (ArithmeticException tooBig) {
      return duration.isNegative() ? Long.MIN_VALUE : Long.MAX_VALUE;
    }
  }

  private Internal() {}

    // Using a try/catch seems lazy, but the catch block will rarely get invoked (except for
    // durations longer than approximately +/- 292 years).
    try {
      return duration.toNanos();
    } catch (ArithmeticException tooBig) {
      return duration.isNegative() ? Long.MIN_VALUE : Long.MAX_VALUE;
    }
  }

  private Internal() {}

    // Using a try/catch seems lazy, but the catch block will rarely get invoked (except for
    // durations longer than approximately +/- 292 years).
    try {
      return duration.toNanos();
    } catch (ArithmeticException tooBig) {
      return duration.isNegative() ? Long.MIN_VALUE : Long.MAX_VALUE;
    }
  }

  private Internal() {}

    // durations longer than approximately +/- 292 years).
    try {
      return duration.toNanos();
    } catch (ArithmeticException tooBig) {
      return duration.isNegative() ? Long.MIN_VALUE : Long.MAX_VALUE;
    }
  }