@davidosborn/crypto-tax-calculator/lib/transaction-filter-stream.js

A tool to calculate the capital gains of cryptocurrency assets for Canadian taxes

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = _default;

var _stream = _interopRequireDefault(require("stream"));

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

/**
 * A stream that filters the transactions.
 */
class TransactionFilterStream extends _stream.default.Transform {
  /**
   * Initializes a new instance.
   * @param {object}       [options]        The options.
   * @param {Set.<string>} [options.assets] The assets to retain.
   */
  constructor(options) {
    super({
      objectMode: true
    });
    this._options = options;
  }
  /**
   * Filters a transaction.
   * @param {Transaction} chunk    The transaction.
   * @param {string}      encoding The encoding type (always 'Buffer').
   * @param {function}    callback A callback for when the transformation is complete.
   */


  async _transform(chunk, encoding, callback) {
    if (!this._options.assets || this._options.assets.has(chunk.asset)) this.push(chunk);
    callback();
  }

}

function _default(...args) {
  return new TransactionFilterStream(...args);
}