auto.js

'use strict';

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

var _once = require('./internal/once.js');

var _once2 = _interopRequireDefault(_once);

var _onlyOnce = require('./internal/onlyOnce.js');

var _onlyOnce2 = _interopRequireDefault(_onlyOnce);

var _wrapAsync = require('./internal/wrapAsync.js');

var _wrapAsync2 = _interopRequireDefault(_wrapAsync);

var _promiseCallback = require('./internal/promiseCallback.js');

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

/**
 * Determines the best order for running the {@link AsyncFunction}s in `tasks`, based on
 * their requirements. Each function can optionally depend on other functions
 * being completed first, and each function is run as soon as its requirements
 * are satisfied.
 *
 * If any of the {@link AsyncFunction}s pass an error to their callback, the `auto` sequence
 * will stop. Further tasks will not execute (so any other functions depending
 * on it will not run), and the main `callback` is immediately called with the
 * error.
 *
 * {@link AsyncFunction}s also receive an object containing the results of functions which
 * have completed so far as the first argument, if they have dependencies. If a
 * task function has no dependencies, it will only be passed a callback.
 *
 * @name auto
 * @static
 * @memberOf module:ControlFlow
 * @method
 * @category Control Flow
 * @param {Object} tasks - An object. Each of its properties is either a
 * function or an array of requirements, with the {@link AsyncFunction} itself the last item
 * in the array. The object's key of a property serves as the name of the task
 * defined by that property, i.e. can be used when specifying requirements for
 * other tasks. The function receives one or two arguments:
 * * a `results` object, containing the results of the previously executed
 *   functions, only passed if the task has any dependencies,
 * * a `callback(err, result)` function, which must be called when finished,
 *   passing an `error` (which can be `null`) and the result of the function's
 *   execution.
 * @param {number} [concurrency=Infinity] - An optional `integer` for
 * determining the maximum number of tasks that can be run in parallel. By
 * default, as many as possible.
 * @param {Function} [callback] - An optional callback which is called when all
 * the tasks have been completed. It receives the `err` argument if any `tasks`
 * pass an error to their callback. Results are always returned; however, if an
 * error occurs, no further `tasks` will be performed, and the results object
 * will only contain partial results. Invoked with (err, results).
 * @returns {Promise} a promise, if a callback is not passed
 * @example
 *
 * //Using Callbacks
 * async.auto({
 *     get_data: function(callback) {
 *         // async code to get some data
 *         callback(null, 'data', 'converted to array');
 *     },