Wrapper for node's buffer allowing writing / reading of individual bits

bit-buffer.js

'use strict';

function BitBuffer(size) {
    size = Math.ceil(size / 8);
    
    this.buffer = new Buffer(size);
    this.buffer.fill(0);
}

BitBuffer.prototype = {
    set: function (index, bool) {
        var pos = index >>> 3;

        if (bool) {
            this.buffer[pos] |= 1 << (index % 8);
        } else {
            this.buffer[pos] &= ~(1 << (index % 8));
        }
    },
    get: function (index) {
        return (this.buffer[index >>> 3] & (1 << (index % 8))) !== 0;
    },
    flip: function (index) {
        this.buffer[index >>> 3] ^= 1 << (index % 8);
    },
    writeBinaryString(value, offset) {
        var bits = value.split('');
        
        offset = offset || 0;
        
        bits.forEach(function (bit, index) {
            this.set(index + offset, bit === '1')
        }, this);
    },
    readBinaryString(offset, length) {
        var result = '';
        
        for (; offset < length; offset++) {
            result += this.get(offset) ? '1' : '0';
        }
        
        return result;
    }
};

module.exports = BitBuffer;