constructor(chart, datasetIndex) {
    this.chart = chart;
    this._ctx = chart.ctx;
    this.index = datasetIndex;
    this._cachedDataOpts = {};
    this._cachedMeta = this.getMeta();
    this._type = this._cachedMeta.type;
    this.options = undefined;
    /** @type {boolean | object} */
    this._parsing = false;
    this._data = undefined;
    this._objectData = undefined;
    this._sharedOptions = undefined;
    this._drawStart = undefined;
    this._drawCount = undefined;
    this.enableOptionSharing = false;
    this.supportsDecimation = false;
    this.$context = undefined;
    this._syncList = [];
    this.datasetElementType = new.target.datasetElementType;
    this.dataElementType = new.target.dataElementType;

    this.initialize();
  }
@param {Chart} chart
@param {number} datasetIndex