blob: 9c4d8f6cab844f55a81f5bf93f227c9729707bfd [file] [log] [blame]
'use strict';
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.default = whilst;
var _noop = require('lodash/noop');
var _noop2 = _interopRequireDefault(_noop);
var _slice = require('./internal/slice');
var _slice2 = _interopRequireDefault(_slice);
var _onlyOnce = require('./internal/onlyOnce');
var _onlyOnce2 = _interopRequireDefault(_onlyOnce);
var _wrapAsync = require('./internal/wrapAsync');
var _wrapAsync2 = _interopRequireDefault(_wrapAsync);
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 {Function} test - synchronous 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 undefined
* @example
*
* var count = 0;
* async.whilst(
* function() { return count < 5; },
* function(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 || _noop2.default);
var _iteratee = (0, _wrapAsync2.default)(iteratee);
if (!test()) return callback(null);
var next = function (err /*, ...args*/) {
if (err) return callback(err);
if (test()) return _iteratee(next);
var args = (0, _slice2.default)(arguments, 1);
callback.apply(null, [null].concat(args));
};
_iteratee(next);
}
module.exports = exports['default'];