whilst.js
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'use strict';
Object.defineProperty(exports, "__esModule", {
value: true
});
var _onlyOnce = require('./internal/onlyOnce');
var _onlyOnce2 = _interopRequireDefault(_onlyOnce);
var _wrapAsync = require('./internal/wrapAsync');
var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
var _awaitify = require('./internal/awaitify');
var _awaitify2 = _interopRequireDefault(_awaitify);
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
/**
* Repeatedly call `iteratee`, while `test` returns `true`. Calls `callback` when
* stopped, or an error occurs.
*
* @name whilst
* @static
* @memberOf module:ControlFlow
* @method
* @category Control Flow
* @param {AsyncFunction} test - asynchronous truth test to perform before each
* execution of `iteratee`. Invoked with ().
* @param {AsyncFunction} iteratee - An async function which is called each time
* `test` passes. Invoked with (callback).
* @param {Function} [callback] - A callback which is called after the test
* function has failed and repeated execution of `iteratee` has stopped. `callback`
* will be passed an error and any arguments passed to the final `iteratee`'s
* callback. Invoked with (err, [results]);
* @returns {Promise} a promise, if no callback is passed
* @example
*
* var count = 0;
* async.whilst(
* function test(cb) { cb(null, count < 5;) },
* function iter(callback) {
* count++;
* setTimeout(function() {
* callback(null, count);
* }, 1000);
* },
* function (err, n) {
* // 5 seconds have passed, n = 5
* }
* );
*/
function whilst(test, iteratee, callback) {
callback = (0, _onlyOnce2.default)(callback);
var _fn = (0, _wrapAsync2.default)(iteratee);
var _test = (0, _wrapAsync2.default)(test);
var results = [];
function next(err, ...rest) {
if (err) return callback(err);
results = rest;
if (err === false) return;
_test(check);
}
function check(err, truth) {
if (err) return callback(err);
if (err === false) return;
if (!truth) return callback(null, ...results);
_fn(next);
}
return _test(check);
}
exports.default = (0, _awaitify2.default)(whilst, 3);
module.exports = exports['default'];