doDuring.js
2 KB
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
'use strict';
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.default = doDuring;
var _noop = require('lodash/noop');
var _noop2 = _interopRequireDefault(_noop);
var _rest = require('./internal/rest');
var _rest2 = _interopRequireDefault(_rest);
var _onlyOnce = require('./internal/onlyOnce');
var _onlyOnce2 = _interopRequireDefault(_onlyOnce);
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
/**
* The post-check version of [`during`]{@link module:ControlFlow.during}. To reflect the difference in
* the order of operations, the arguments `test` and `fn` are switched.
*
* Also a version of [`doWhilst`]{@link module:ControlFlow.doWhilst} with asynchronous `test` function.
* @name doDuring
* @static
* @memberOf module:ControlFlow
* @method
* @see [async.during]{@link module:ControlFlow.during}
* @category Control Flow
* @param {Function} fn - A function which is called each time `test` passes.
* The function is passed a `callback(err)`, which must be called once it has
* completed with an optional `err` argument. Invoked with (callback).
* @param {Function} test - asynchronous truth test to perform before each
* execution of `fn`. Invoked with (...args, callback), where `...args` are the
* non-error args from the previous callback of `fn`.
* @param {Function} [callback] - A callback which is called after the test
* function has failed and repeated execution of `fn` has stopped. `callback`
* will be passed an error if one occured, otherwise `null`.
*/
function doDuring(fn, test, callback) {
callback = (0, _onlyOnce2.default)(callback || _noop2.default);
var next = (0, _rest2.default)(function (err, args) {
if (err) return callback(err);
args.push(check);
test.apply(this, args);
});
function check(err, truth) {
if (err) return callback(err);
if (!truth) return callback(null);
fn(next);
}
check(null, true);
}
module.exports = exports['default'];