parallel-universe/repeat.js

The set of async flow control structures and promise utils.

'use strict';

var AbortablePromise = require('./AbortablePromise.js');
var utils = require('./utils.js');

function repeat(cb, ms, until) {
    return new AbortablePromise.AbortablePromise((resolve, reject, signal) => {
        let timer;
        signal.addEventListener('abort', () => {
            clearTimeout(timer);
        });
        (function next(index) {
            new Promise(resolve => {
                resolve(utils.withSignal(cb(signal, index), signal));
            })
                .then(value => {
                if (signal.aborted) {
                    return;
                }
                if (until !== undefined && until(value, index)) {
                    resolve(value);
                    return;
                }
                timer = setTimeout(next, typeof ms === 'function' ? ms(value, index) : ms, index + 1);
            })
                .catch(reject);
        })(0);
    });
}

exports.repeat = repeat;