Blame view

node_modules/async/reflect.js 2.32 KB
aaac7fed   liuqimichale   add
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
  'use strict';
  
  Object.defineProperty(exports, "__esModule", {
      value: true
  });
  exports.default = reflect;
  
  var _initialParams = require('./internal/initialParams');
  
  var _initialParams2 = _interopRequireDefault(_initialParams);
  
  var _slice = require('./internal/slice');
  
  var _slice2 = _interopRequireDefault(_slice);
  
  var _wrapAsync = require('./internal/wrapAsync');
  
  var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
  
  function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
  
  /**
   * Wraps the async function in another function that always completes with a
   * result object, even when it errors.
   *
   * The result object has either the property `error` or `value`.
   *
   * @name reflect
   * @static
   * @memberOf module:Utils
   * @method
   * @category Util
   * @param {AsyncFunction} fn - The async function you want to wrap
   * @returns {Function} - A function that always passes null to it's callback as
   * the error. The second argument to the callback will be an `object` with
   * either an `error` or a `value` property.
   * @example
   *
   * async.parallel([
   *     async.reflect(function(callback) {
   *         // do some stuff ...
   *         callback(null, 'one');
   *     }),
   *     async.reflect(function(callback) {
   *         // do some more stuff but error ...
   *         callback('bad stuff happened');
   *     }),
   *     async.reflect(function(callback) {
   *         // do some more stuff ...
   *         callback(null, 'two');
   *     })
   * ],
   * // optional callback
   * function(err, results) {
   *     // values
   *     // results[0].value = 'one'
   *     // results[1].error = 'bad stuff happened'
   *     // results[2].value = 'two'
   * });
   */
  function reflect(fn) {
      var _fn = (0, _wrapAsync2.default)(fn);
      return (0, _initialParams2.default)(function reflectOn(args, reflectCallback) {
          args.push(function callback(error, cbArg) {
              if (error) {
                  reflectCallback(null, { error: error });
              } else {
                  var value;
                  if (arguments.length <= 2) {
                      value = cbArg;
                  } else {
                      value = (0, _slice2.default)(arguments, 1);
                  }
                  reflectCallback(null, { value: value });
              }
          });
  
          return _fn.apply(this, args);
      });
  }
  module.exports = exports['default'];