What is Test-Driven Development?

Everyone wants to deploy bug-free code, but creating software with no issues or bugs is the unicorn of the development world. It doesn’t exist, but developers can take steps to ensure that their code has the least amount of bugs possible. Test-driven development (TDD) is one way that developers can reduce bugs in their system and make business owners happy about the outcome of projects.

How Does TDD Work?

TDD is a methodology, not a programming language or syntax. Every organisation implements it differently. The main methodologies used in TDD are:

  • Create tests before you develop software, so you already know if your code has bugs before launch.
  • Run tests while the code is in development, so logic flaws are found quickly.
  • Refactor code to fix bugs while software is in development, so your bug fix procedures are implemented before the faulty code is released to the public.

In essence, test code is created while developers create your software. These tests mainly catch logic flaws, which are difficult to identify before users work with your software. Logic errors are the main enemy of every coder, and they can create serious, critical errors in both data storage, user output, and security.

Even if you have a QA department, logic flaws are often missed and introduced to production software. QA is responsible for catching these errors, but it’s nearly impossible to catch every error. You must think like a user to find them, and there is always one user that is able to accidentally find a coding flaw. Hackers purposely look for these flaws to exploit your software.

Advantages of TDD

Bug-free code is one advantage of TDD, but there are others. Developers understand your users a lot better when they are forced to figure out ways that software can be broken. It also helps bubble up problems that might otherwise be buried in requirements. Usually, logic errors aren’t found until users begin to use your software, so the challenge is to find them before your users do. You can’t identify how a user will understand your software, but using tests gets developers closer to the user as they work through every test possibility.

Using TDD will increase confidence in your code during launch. It’s stressful when your software deploys to the public, but you can reduce the stress when you know that your software has been thoroughly tested.

Disadvantages of TDD

With its advantages, TDD has some disadvantages that you should consider. They mainly affect your budget. TDD takes time, so it increases development time for your projects as well as the code base and while this isn’t a critical issue, it can be a problem when you’re debugging and need to change your tests as well.

You should never use TDD to replace true testing. It can reduce bugs, but a QA team is still important for finding anything a coder didn’t consider. You can, however, complement QA testing with TDD to greatly reduce production issues and user frustration.

Andy Joyce

A true app aficionado. Andy is constantly developing and striving to make his apps stand out from the crowd.