Unit Testing

Unit Testing

What is Unit Testing?

Unit Testing is the practice of testing certain logical units of functionality in your code. It gives us the ability to verify that each unit of the code works as intended.
Unit tests may be written for individual functions, or parts of functionality encompassing several methods or even classes.

What exactly is a unit test supposed to do?

A unit test is supposed to automate the performing certain actions, or provide certain input to the unit that is being tested, and match that with a specific output, or outcome.

Why should I write tests?

Unit tests may seem like more work to do, but in the long run, will save you several hours, if not days of work. They allow you to ensure that the test cases are valid for every version of the software, reducing debugging, and testing time.

Advantages of Unit Testing

• It is automated, and thus allows you to not have to manually test, later
• It saves time, since a test written once is useful throughout
• Tests can range from extremely simple to extremely sophisticated use-cases, making them flexible

When to not write unit tests

Unit tests need not be written, when the application being built is trivially simple, and writing tests would be a significant fraction of the development time

Incorporating Unit Testing into your Development Workflow

Unit testing is continuous work, and should be done when writing the module itself. This is the best time to write the test, as you are clearest with the logic of the module.

Misc

Writing testable code
This is a nice guide on writing clean, testable, and maintainable code, as well as writing good tests to go along with it