mach-react/src/setZeroTimeout.js

Fast, and tiny react implementation.

'use strict';

let timeouts = [];
let messageName = 'zero-timeout-message';

let ids = {};

export default function setZeroTimeout(fn) {
  // TODO: add MutationObserver

  if (global.postMessage) {
    if (timeouts.indexOf(fn) === -1) timeouts.push(fn);
    return global.postMessage(messageName, '*');
  }

  ids[setTimeout(fn, 0)] = fn;
}

export function unsetZeroTimeout(fn) {
  // TODO: remove MutationObserver

  if (global.postMessage) {
    let index = timeouts.indexOf(fn);
    if (index === -1) timeouts[index] = null;
    return;
  }

  clearTimeout(findId(fn));
}

function findId(fn) {
  for (let id in ids) if (ids[id] === fn) return id;
  return null;
}

if (typeof window !== 'undefined') {
  window.addEventListener('message', handleMessage, true);
}

else {
  console.error(new Error('setZeroTimeout unavailable.'));
}

function handleMessage(event) {
  if (event.source === window && event.data === messageName) {
    event.stopPropagation();
    if (timeouts.length > 0) {
      let fn = timeouts.shift();
      if (fn) fn();
    }
  }
}