justsml

// Promises are great, but bluebird covers :allthethings
var Promise       = require('bluebird');
var appContext    = {ready: false, error: false};
const INVALID_CTX = {ready: false, error: true, message: 'App or User not initialized'};

// Bluebird-ify around `fetch` API
function getUser(username) {return Promise.resolve('users/' + username + '.json').then(fetch);}

function initApp(username) {
  // Use bluebird to do some real-world-ish code: 

justsml

/*
* Updated w/ insertAdjacentElement
* @author Dan Levy @justsml
* 2016-06-23
*
* Credit: @lyleunderwood - afterend patch/fix
*
* ```js
* import { insertAdjacentElement } from './libs/insertAdjacentHTML.js';
* Use either:

justsml

Idiomatic React Testing Patterns

Testing React components seems simple at first. Then you need to test something that isn't a pure interaction and things seem to break down. These 4 patterns should help you write readable, flexible tests for the type of component you are testing.

Setup

I recommend doing all setup in the most functional way possible. If you can avoid it, don't set variables in a beforeEach. This will help ensure tests are isolated and make things a bit easier to reason about. I use a pattern that gives great defaults for each test example but allows every example to override props when needed:

justsml

// transformy is an object mapping tool to 
// transform objects to another object defaults
function transformy({ mutate = {}, input = {}, schema = {}, omit = [], loose = true }) {
  return Object.keys(input).map((key) => {
    const mutated = {};
    const tkey    = mutate.hasOwnProperty(key) ? mutate[key] : null;
    if (omit.indexOf(key) !== -1) return mutated;
    if (typeof input[key] !== 'undefined' && schema.hasOwnProperty(tkey)) {
      mutated[tkey] = input[key];
    } else if (typeof schema[key] !== 'undefined') { 

justsml

const EventEmitter = require('events');

class Eventry extends EventEmitter {
  constructor(type = 'none', ...args) {
    super(args);
    this.type = type;
  }
  // overload .on and .emit func to
  // support special event syntax
  on(ev, fn) {

justsml

const makeRequest = () => {
  return getJSON()
  .then(data => data.needsAnotherRequest
      ? makeAnotherRequest(data)
      : data)
  .then(data => console.log(data) || data) 
}

justsml

import React from 'react';

const MIN_SCALE = 1;
const MAX_SCALE = 4;
const SETTLE_RANGE = 0.001;
const ADDITIONAL_LIMIT = 0.2;
const DOUBLE_TAP_THRESHOLD = 300;
const ANIMATION_SPEED = 0.04;
const RESET_ANIMATION_SPEED = 0.08;
const INITIAL_X = 0;

justsml

dialog {
	position: fixed;
	top: 50%;
	left: 50%;
	right: auto;
	padding: 30px;
	transform: perspective(500px) translate(-50%, -50%);
	background: linear-gradient(to bottom, #FFF, #F4F4F4) #FFF;
	border: none;
	border-radius: 3px;

justsml

const Bluebird = require('bluebird')
const got = require('got')

const urls = [
  "http://www.google.com/",
  "http://www.yahoo.com/",
  "http://www.bing.com/",
];

// Bluebird is an extension of promises:

justsml

#!/bin/bash
#
# Set up OSX preferences
#
# Updated By: Dan Levy @justsml
#
# Inspired by: https://github.com/mathiasbynens/dotfiles/blob/master/.osx
###########################################
# CONFIG