[Bug Fix] Edge case: BitSet when highest bit index is a multiplication of 32

[yanivshaked]

Hi,

The following test will fail on existing code:

    test('bit sets (edge case)', () {
      final counter = BitCounter(0);
      counter.addBitSet(ListSet.fromSorted([0, 2, 5, 2048]));
      expect(counter[2048], 1);
    });

The reason for that is that 2048 / 32 is an integer number, so the hasExtra value in _bufferLength32 will be 0.
In this edge case (whenever the highest bit index for bit set is a multiplication of 32), the bit array size will not be sufficient (one bit missing).
The corret fix is to use last bit index +1 for the length of the bit array (see commit).

[isoos]

I'm wondering if the BitSet.length's definition is wrong, especially because the documentation differs on the range between BitSet and BitArray. Maybe it would be better to rename/change the field and update what it returns? wdyt?

[yanivshaked]

Correct. I think the name length should remain, but the value returned should be changed:

  int get length => _list.isEmpty ? 0 : _list.last + 1;

wdyt?

[isoos]

Yes, I think that should be the right fix here.

[yanivshaked]

I have updated the fix, please review and merge.