qborreda

/**
 * React custom hook to fire a function given an interval
 * @usage: useInterval(()=>{...},1000);
**/
function useInterval(callback, delay) {
  const savedCallback = useRef();

  useEffect(() => {
    savedCallback.current = callback;
  });

qborreda

const compose = (...fns) => fns.reduce((f, g) => (...args) => f(g(...args)));
/*
const add5 = x => x + 5
const multiply = (x, y) => x * y
const multiplyAndAdd5 = compose(add5, multiply)
multiplyAndAdd5(5, 2) -> 15
*/

qborreda

function flattenArray(arr) {
  let found = [];

  arr.map((elem, index) => {
    if (Array.isArray(elem)) {
      found = found.concat(flattenArray(elem));
    } else {
      found.push(elem);
    }
  });

qborreda

let filenames = ['index.html', 'blog.html', 'terms.html'];

Promise.all(filenames.map(readFilePromise))
  .then(files => {
    console.log('index:', files[0]);
    console.log('blog:', files[1]);
    console.log('terms:', files[2]);
  })

qborreda

export function setCookie(c_name, value, exdays, domain) {
  let exdate = new Date();
  let time = exdate.getTime();
  time += 3600 * 1000;
  exdate.setTime(time);
  exdate.setDate(exdate.getDate() + exdays);
  let c_value =
    escape(value) + (exdays == null ? '' : '; expires=' + exdate.toUTCString());
  c_value += domain ? ';domain=' + domain : '';
  c_value += ';path=/';

qborreda

The Ultimate Unit Testing Cheat-sheet

For Mocha, Chai and Sinon

using mocha/chai/sinon for node.js unit-tests? check out my utility: mocha-stirrer to easily reuse test components and mock require dependencies

---

• Sinon Chai
• Chai
• Sinon
• Mocha

qborreda

const objArr = [
  { letter: 'a', num: 1 },
  { letter: 'b', num: 2 },
  { letter: 'c', num: 3 }
]

const updateObjInArr = (oldArr, searchKey, oldVal, newVal) => {
  return oldArr.map(item => {
    if (item[searchKey] === oldVal) {
      item[searchKey] = newVal

qborreda

var uniqueArray = function(arrArg) {
  return arrArg.filter(function(elem, pos,arr) {
    return arr.indexOf(elem) == pos;
  });
};

var uniqEs6 = (arrArg) => {
  return arrArg.filter((elem, pos, arr) => {
    return arr.indexOf(elem) == pos;
  });

qborreda

const getProp = (obj, key) =>
    key.split('.').reduce( (o, x) =>
        (typeof o == "undefined" || o === null) ? o : o[x]
    , obj);

qborreda

/*
 * promiseSerial resolves Promises sequentially.
 * @example
 * const urls = ['/url1', '/url2', '/url3']
 * const funcs = urls.map(url => () => $.ajax(url))
 *
 * promiseSerial(funcs)
 *   .then(console.log)
 *   .catch(console.error)
 */