Introduction to Test Driven Development

Test Driven Development (TDD) is one of the primitive software development methodology and is often associated with XP as many of the concepts overlap. It is an approach which focuses developing the Test Cases before the code is written.  The TDD is based around 3 activities; Coding, Testing and Design.

Test-driven development (TDD), also known as Test First Development (TFD), TDD and TFD encourage bringing a different mindset to development by providing them with a base vision of the scope and dimension, utilizing which the developers can employ short tests and can have number of short feedback cycles.

Test driven development process is illustrated in form of UML diagram below which revolved around its 3 main components; Code, Testing, Design/Refactoring.

TDD Process

Levels of Test Driven Development

The Test Driven Development is conducted at two different levels:

Acceptance TDD (ATDD): It moves the testing focus from the code to the business requirement and Tests are created before the work on code starts. The goal of ATDD is to specify detailed, executable requirements for your solution on a just in time (JIT) basis. ATDD is also called Behavior Driven Development (BDD). Accepted levels are termed as “FIT” (Framework for Integrating Testing) or “FitNesse”. The overall process goes through 4 stages; discuss the requirements, distill tests in a framework-friendly environment, develop the code and hook up the tests, Demo.

Developer TDD: With developer TDD, the developer writes unit test before writing the code. It allows the developer to focus on test small chunks of production code and test it before moving further.

ATDD and developer TDD working together