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import onlyOnce from './internal/onlyOnce';
import wrapAsync from './internal/wrapAsync';
import awaitify from './internal/awaitify'
/**
* The post-check version of [`whilst`]{@link module:ControlFlow.whilst}. To reflect the difference in
* the order of operations, the arguments `test` and `iteratee` are switched.
*
* `doWhilst` is to `whilst` as `do while` is to `while` in plain JavaScript.
*
* @name doWhilst
* @static
* @memberOf module:ControlFlow
* @method
* @see [async.whilst]{@link module:ControlFlow.whilst}
* @category Control Flow
* @param {AsyncFunction} iteratee - A function which is called each time `test`
* passes. Invoked with (callback).
* @param {AsyncFunction} test - asynchronous truth test to perform after each
* execution of `iteratee`. Invoked with (...args, callback), where `...args` are the
* non-error args from the previous callback of `iteratee`.
* @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
*/
function doWhilst(iteratee, test, callback) {
callback = onlyOnce(callback);
var _fn = wrapAsync(iteratee);
var _test = wrapAsync(test);
var results
function next(err, ...args) {
if (err) return callback(err);
if (err === false) return;
results = args
_test(...args, check);
}
function check(err, truth) {
if (err) return callback(err);
if (err === false) return;
if (!truth) return callback(null, ...results);
_fn(next);
}
return check(null, true);
}
export default awaitify(doWhilst, 3)
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