Book Image

DART Essentials

By : Sikora
Book Image

DART Essentials

By: Sikora

Overview of this book

This book is targeted at expert programmers in JavaScript who want to learn Dart quickly. Some previous experience with OOP programming in other languages and a good knowledge of JavaScript are assumed.
Table of Contents (11 chapters)
10
Index

Unit testing


The motivation for writing unit tests shouldn't just be a simple way to test existing code, there are more benefits to consider:

  • The fundamental idea behind unit tests is to write isolated testable code. To achieve this, it makes developers write smaller single-purpose methods and therefore avoid writing long spaghetti-like code.

  • Refactoring existing code is easier because you can rewrite and test code in smaller portions. Refactored code should pass the same tests as the original code.

  • Tests themselves can be considered as documentation and examples of expected behavior.

For this example, we'll write a console application that finds all numbers that are prime numbers, and all its digits are used only once. This is, for example, the number 941, because it's a prime number and contains each digit only once. On the other hand, the number 1,217 is a prime number but contains the digit 1 twice, so that's not what we're looking for.

Then, we'll extend our example with another method that...