Test-Driven Development vs Behaviour-Driven Development

web development company

Individuals working in a web development and digital marketing company should be aware of what is involved when it comes to unit testing, test-driven development (TDD) and behaviour-driven development (BDD).

What is Test-Driven Development (TDD)?

In a nutshell, test-driven development is a test that is written (before the code) and run by the developer. This reduces the number of bugs and increases the percentage of code tested automatically, so maintaining the state of the code while adding new features is relatively simple. The fact that the test is typically written before the code in TDD means the developer has to focus on the requirements of the website and its desired functionalities before writing the actual code.

TDD relies on a short development cycle which is repeated. Requirements can then be turned into specific test cases and the code will be constantly improved to pass new tests until any bugs are eliminated.

TDD Steps:

  1. Add a test – Developers will write a test that defines a function or the improvements for an already existing function. Some may choose to use a modified test they have already written.
  2. Run test and see if it fails – This will tell the developer if the test harness (automated test framework) is functioning properly. Writing a failing test allows the developer to fix it so that the code passes the test.
  3. Write the code – Write new code which allows it to pass the test. It may not pass perfectly, but it will be polished and finalised in the refactoring stage (5).
  4. Run tests – This stage will determine if the new functions pass the test requirements without negatively affecting any existing functions.
  5. Refactor code – During this stage code is constantly cleaned up and can be moved back to where it is more logically needed before it was moved for more convenient testing. Cleaning up code involves removing duplicates, clearly labelling objects, methods and classes with their current purpose, while intermediately running the test again to be sure functionalities are unaltered by the cleaning.
  6. Repeat – The cycle is repeated because only 10 edits should be made in each test run. The process is repeated until the completed code passes all tests.

What is Behaviour-Driven Development (BDD)?

BDD has grown from TDD in order to streamline the process. When behaviour-driven development is applied to automated testing it can be considered the set of best practices which makes for writing the best tests. BDD is a level 3 approach and can be considered a combination of TDD principles and the ideas set by domain-driven design and object-oriented analysis. BDD helps to manage software development for both business goals and technical insights. BDD lends its focus from TDD in that the testing method is determined before the code in order to determine the best place to start in the coding process as well as what requires testing and what doesn’t.  

BDD is based in understanding what the client wants by creating communication between developers, testers and business people. Tests are automated to drive behaviour.

For comprehensive web development services, Starbright simply requires you to share with us what you want your website to be. From there the members of our web development and digital marketing teams will build and grow your business to increase your ROI, create engagement and brand recognition, and make sure you are the top-ranked website on Google in your market. As a website development company, Starbright can help you to build your business online, contact us for more details.