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import noop from 'lodash/noop';
import rest from './internal/rest';
import onlyOnce from './internal/onlyOnce';
import wrapAsync from './internal/wrapAsync';
/**
* 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 {Function} iteratee - 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 - synchronous truth test to perform after each
* execution of `iteratee`. Invoked with the non-error callback results 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]);
*/
export default function doWhilst(iteratee, test, callback) {
callback = onlyOnce(callback || noop);
var _iteratee = wrapAsync(iteratee);
var next = rest(function(err, args) {
if (err) return callback(err);
if (test.apply(this, args)) return _iteratee(next);
callback.apply(null, [null].concat(args));
});
_iteratee(next);
}
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