Book Image

Learning TypeScript 2.x - Second Edition

By : Remo H. Jansen
Book Image

Learning TypeScript 2.x - Second Edition

By: Remo H. Jansen

Overview of this book

TypeScript is an open source and cross-platform statically typed superset of JavaScript that compiles to plain JavaScript and runs in any browser or host. This book is a step-by-step guide that will take you through the use and benefits of TypeScript with the help of practical examples. You will start off by understanding the basics as well as the new features of TypeScript 2.x. Then, you will learn how to work with functions and asynchronous programming APIs. You will continue by learning how to resolve runtime issues and how to implement TypeScript applications using the Object-oriented programming (OOP) and functional programming (FP) paradigms. Later, you will automate your development workflow with the help of tools such as Webpack. Towards the end of this book, you will delve into some real-world scenarios by implementing some full-stack TypeScript applications with Node.js, React and Angular as well as how to optimize and test them. Finally, you will be introduced to the internal APIs of the TypeScript compiler, and you will learn how to create custom code analysis tools.
Table of Contents (17 chapters)

Testing terminology

Throughout this chapter, we are going to use some concepts that may not be familiar to readers without previous experience in the field of software testing. For this reason, we are going to take a quick look at some of the most popular concepts in software testing before we get started.


An assertion is a condition that must be tested to confirm that a certain piece of code behaves as expected, or, in other words, to confirm conformance to a requirement.

Let's imagine that we are working as part of the Google Chrome development team, and we must implement the JavaScript Math API. If we are working on the pow method, the requirement could be something like, the Math.pow (base, exponent) function...