Brian Riley brianmriley

The introduction to Reactive Programming you've been missing

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

Better Jasmine Tests With `this`

On the Refinery29 Mobile Web Team, codenamed "Bicycle", all of our unit tests are written using Jasmine, an awesome BDD library written by Pivotal Labs. We recently switched how we set up data for tests from declaring and assigning to closures, to assigning properties to each test case's this object, and we've seen some awesome benefits from doing such.

The old way

Up until recently, a typical unit test for us looked something like this:

describe('views.Card', function() {

	/// <reference path="../typings/tsd.d.ts" />

	import db = require('../db/db');
	import IAuthorDocument = require('../db/IAuthorDocument');

	class Author {
	private _author:IAuthorDocument;

	constructor(author:IAuthorDocument) {
	this._author = author;

	/**
	* Implement a tryCatch() method that logs exceptions for method invocations AND
	* promise rejection activity.
	*
	* @param notifyFn Function callback with logging/exception information (typically $log.error )
	* @param scope Object Receiver for the notifyFn invocation ( optional )
	*
	* @return Function used to guard and invoke the targeted actionFn
	*/
	function makeTryCatch( notifyFn, scope )

	/**
	* Creates a new Uint8Array based on two different ArrayBuffers
	*
	* @private
	* @param {ArrayBuffers} buffer1 The first buffer.
	* @param {ArrayBuffers} buffer2 The second buffer.
	* @return {ArrayBuffers} The new ArrayBuffer created out of the two.
	*/
	var _appendBuffer = function(buffer1, buffer2) {
	var tmp = new Uint8Array(buffer1.byteLength + buffer2.byteLength);

	// Source: https://groups.google.com/forum/#!topic/angular/hVrkvaHGOfc
	// jsFiddle: http://jsfiddle.net/pkozlowski_opensource/PxdSP/14/
	// author: Pawel Kozlowski

	var myApp = angular.module('myApp', []);

	//service style, probably the simplest one
	myApp.service('helloWorldFromService', function() {
	this.sayHello = function() {
	return "Hello, World!"

	"use strict";

	// `f` is assumed to sporadically fail with `TemporaryNetworkError` instances.
	// If one of those happens, we want to retry until it doesn't.
	// If `f` fails with something else, then we should re-throw: we don't know how to handle that, and it's a
	// sign something went wrong. Since `f` is a good promise-returning function, it only ever fulfills or rejects;
	// it has no synchronous behavior (e.g. throwing).
	function dontGiveUp(f) {
	return f().then(
	undefined, // pass through success

	var hexChar = ["0", "1", "2", "3", "4", "5", "6", "7","8", "9", "A", "B", "C", "D", "E", "F"];

	function byteToHex(b) {
	return hexChar[(b >> 4) & 0x0f] + hexChar[b & 0x0f];
	}

	<!DOCTYPE html>
	<html>
	<head>
	<script data-main="usage" src="http://requirejs.org/docs/release/1.0.8/comments/require.js"></script>
	</head>
	<body>
	<p>Check your JavaScript console for output!</p>
	</body>
	</head>

Brian Riley brianmriley

The introduction to Reactive Programming you've been missing

This tutorial as a series of videos

Better Jasmine Tests With this

The old way

Better Jasmine Tests With `this`