JavaScript utility for generating random stuff and doing stuff randomly

Chaos.js

import {promiseWhile} from './promiseWhile';

/**
 * Flip a coin!
 *
 * @returns {Boolean}
 */
function randomBool() {
    return Math.random() < 0.5;
}

/**
 * Generate a random number between min and max, inclusive
 *
 * @param {Number} min
 * @param {Number} max
 * @returns {Number}
 */
function randomInt(min, max) {
    return (Math.floor(Math.random() * (max - min))) + min;
}

/**
 * Repeatedly execute a function at random intervals.
 *
 * @param {Function} func – the function to execute
 * @param {Number} min – the minimum time to sleep between executions of the function
 * @param {Number} max – the maximum time to sleep between executions of the function
 * @returns {Function} – a cleanup function to stop executing the function at random intervals
 */
function execAtRandomIntervals(func, min, max) {
    let shouldContinue = true;
    promiseWhile(
        () => shouldContinue,
        () => new Promise((resolve) => {
            const sleep = randomInt(min, max);
            setTimeout(() => {
                func();
                resolve();
            }, sleep);
        }),
    );
    return () => shouldContinue = false;
}

export {
    randomBool,
    randomInt,
    execAtRandomIntervals,
};

promiseWhile.js

/**
 * Simulates a while loop where the condition is determined by the result of a Promise.
 *
 * @param {Function} condition
 * @param {Function} action
 * @returns {Promise}
 */
export default function promiseWhile(condition, action) {
    return new Promise((resolve, reject) => {
        const loop = function () {
            if (!condition()) {
                resolve();
            } else {
                Promise.resolve(action())
                    .then(loop)
                    .catch(reject);
            }
        };
        loop();
    });
}