@graffy/common/esm/stream/mergeStreams.js

Common libraries that used by various Graffy modules.

import _wrapAsyncGenerator from "@babel/runtime/helpers/esm/wrapAsyncGenerator";
import _awaitAsyncGenerator from "@babel/runtime/helpers/esm/awaitAsyncGenerator";
import _asyncIterator from "@babel/runtime/helpers/esm/asyncIterator";
import _asyncGeneratorDelegate from "@babel/runtime/helpers/esm/asyncGeneratorDelegate";

function _createForOfIteratorHelperLoose(o, allowArrayLike) { var it; if (typeof Symbol === "undefined" || o[Symbol.iterator] == null) { if (Array.isArray(o) || (it = _unsupportedIterableToArray(o)) || allowArrayLike && o && typeof o.length === "number") { if (it) o = it; var i = 0; return function () { if (i >= o.length) return { done: true }; return { done: false, value: o[i++] }; }; } throw new TypeError("Invalid attempt to iterate non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method."); } it = o[Symbol.iterator](); return it.next.bind(it); }

function _unsupportedIterableToArray(o, minLen) { if (!o) return; if (typeof o === "string") return _arrayLikeToArray(o, minLen); var n = Object.prototype.toString.call(o).slice(8, -1); if (n === "Object" && o.constructor) n = o.constructor.name; if (n === "Map" || n === "Set") return Array.from(o); if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _arrayLikeToArray(o, minLen); }

function _arrayLikeToArray(arr, len) { if (len == null || len > arr.length) len = arr.length; for (var i = 0, arr2 = new Array(len); i < len; i++) { arr2[i] = arr[i]; } return arr2; }

import mergeIterators from 'merge-async-iterators';
import { merge } from '../ops';
export default function mergeStreams() {
  return _mergeStreams.apply(this, arguments);
}

function _mergeStreams() {
  _mergeStreams = _wrapAsyncGenerator( /*#__PURE__*/regeneratorRuntime.mark(function _callee() {
    var _len,
        streams,
        _key,
        firstValues,
        _iterator,
        _step,
        value,
        merged,
        _iterator2,
        _step2,
        _value,
        _args = arguments;

    return regeneratorRuntime.wrap(function _callee$(_context) {
      while (1) {
        switch (_context.prev = _context.next) {
          case 0:
            for (_len = _args.length, streams = new Array(_len), _key = 0; _key < _len; _key++) {
              streams[_key] = _args[_key];
            }

            _context.next = 3;
            return _awaitAsyncGenerator(Promise.all(streams.map(function (stream) {
              return stream.next();
            })));

          case 3:
            firstValues = _context.sent.map(function (iter) {
              return iter.value;
            });

            if (!firstValues.some(function (value) {
              return typeof value === 'undefined';
            })) {
              _context.next = 17;
              break;
            }

            _context.next = 7;
            return undefined;

          case 7:
            _iterator = _createForOfIteratorHelperLoose(firstValues);

          case 8:
            if ((_step = _iterator()).done) {
              _context.next = 15;
              break;
            }

            value = _step.value;

            if (!(typeof value !== 'undefined')) {
              _context.next = 13;
              break;
            }

            _context.next = 13;
            return value;

          case 13:
            _context.next = 8;
            break;

          case 15:
            _context.next = 21;
            break;

          case 17:
            merged = [];

            for (_iterator2 = _createForOfIteratorHelperLoose(firstValues); !(_step2 = _iterator2()).done;) {
              _value = _step2.value;
              merge(merged, _value);
            }

            _context.next = 21;
            return merged;

          case 21:
            return _context.delegateYield(_asyncGeneratorDelegate(_asyncIterator(mergeIterators(streams)), _awaitAsyncGenerator), "t0", 22);

          case 22:
          case "end":
            return _context.stop();
        }
      }
    }, _callee);
  }));
  return _mergeStreams.apply(this, arguments);
}