redux-saga/lib/internal/sagaHelpers/fsmIterator.js

Saga middleware for Redux to handle Side Effects

'use strict';

exports.__esModule = true;
exports.qEnd = undefined;
exports.safeName = safeName;
exports.default = fsmIterator;

var _utils = /*#__PURE__*/require('../utils');

var done = { done: true, value: undefined };
var qEnd = exports.qEnd = {};

function safeName(patternOrChannel) {
  if (_utils.is.channel(patternOrChannel)) {
    return 'channel';
  } else if (Array.isArray(patternOrChannel)) {
    return String(patternOrChannel.map(function (entry) {
      return String(entry);
    }));
  } else {
    return String(patternOrChannel);
  }
}

function fsmIterator(fsm, q0) {
  var name = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : 'iterator';

  var updateState = void 0,
      qNext = q0;

  function next(arg, error) {
    if (qNext === qEnd) {
      return done;
    }

    if (error) {
      qNext = qEnd;
      throw error;
    } else {
      updateState && updateState(arg);

      var _fsm$qNext = fsm[qNext](),
          q = _fsm$qNext[0],
          output = _fsm$qNext[1],
          _updateState = _fsm$qNext[2];

      qNext = q;
      updateState = _updateState;
      return qNext === qEnd ? done : output;
    }
  }

  return (0, _utils.makeIterator)(next, function (error) {
    return next(null, error);
  }, name, true);
}