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1'use strict';
2
3Object.defineProperty(exports, "__esModule", {
4 value: true
5});
6
7var _onlyOnce = require('./internal/onlyOnce');
8
9var _onlyOnce2 = _interopRequireDefault(_onlyOnce);
10
11var _wrapAsync = require('./internal/wrapAsync');
12
13var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
14
15var _awaitify = require('./internal/awaitify');
16
17var _awaitify2 = _interopRequireDefault(_awaitify);
18
19function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
20
21/**
22 * The post-check version of [`whilst`]{@link module:ControlFlow.whilst}. To reflect the difference in
23 * the order of operations, the arguments `test` and `iteratee` are switched.
24 *
25 * `doWhilst` is to `whilst` as `do while` is to `while` in plain JavaScript.
26 *
27 * @name doWhilst
28 * @static
29 * @memberOf module:ControlFlow
30 * @method
31 * @see [async.whilst]{@link module:ControlFlow.whilst}
32 * @category Control Flow
33 * @param {AsyncFunction} iteratee - A function which is called each time `test`
34 * passes. Invoked with (callback).
35 * @param {AsyncFunction} test - asynchronous truth test to perform after each
36 * execution of `iteratee`. Invoked with (...args, callback), where `...args` are the
37 * non-error args from the previous callback of `iteratee`.
38 * @param {Function} [callback] - A callback which is called after the test
39 * function has failed and repeated execution of `iteratee` has stopped.
40 * `callback` will be passed an error and any arguments passed to the final
41 * `iteratee`'s callback. Invoked with (err, [results]);
42 * @returns {Promise} a promise, if no callback is passed
43 */
44function doWhilst(iteratee, test, callback) {
45 callback = (0, _onlyOnce2.default)(callback);
46 var _fn = (0, _wrapAsync2.default)(iteratee);
47 var _test = (0, _wrapAsync2.default)(test);
48 var results;
49
50 function next(err, ...args) {
51 if (err) return callback(err);
52 if (err === false) return;
53 results = args;
54 _test(...args, check);
55 }
56
57 function check(err, truth) {
58 if (err) return callback(err);
59 if (err === false) return;
60 if (!truth) return callback(null, ...results);
61 _fn(next);
62 }
63
64 return check(null, true);
65}
66
67exports.default = (0, _awaitify2.default)(doWhilst, 3);
68module.exports = exports['default'];
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