TDD Vs BDD: The Differences Decoded


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TDD stands for test-driven development. It means writing a test that fails because the designated functionality doesn’t exist, then writing the simple code that could make the test pass and refactoring for removing duplication. This red-green-refactor loop is repeated over and over until you achieve a complete feature. BDD is behaviour-driven development. It means designing an executable specification that fails because the feature doesn’t exist than writing the simplest code that could make the spec pass. You can repeat this until a release candidate is ready to ship.

Both TDD vs BDD seem pretty similar, but the key difference between the two is the scope. TDD is a practice in growth and BDD a team approach. Developers write the tests in TDD while users or testers create automatic specifications with developers wearing them with the code under test in BDD. TDD and BDD effectively the same for small co-located and developer-centric teams.

Test design

The best writing takes place ahead of the code in both BDD vs TDD. Writing tests first will help protect the course of development that will ultimately prevent any cases from being missed from the code of functionality. Both methods are involved with locating barks, and they also act as concrete documentation of what the test coverage aims to achieve.

Test method

Tests are programmed within this approach that calls for strong coding skills. They are allowed to be automated for later use by programming.


The team thanks us for discussing and coming up with ideas in Planning. The ideas then become tests, but first, the test is designed and expected to fail. Then the code is written to enable the test to pass. As the test has passed, the code is a risk factor for others until the best design eventually images for stop this new factor code continues to be under test until design finalization.

Process of TDD

A very basic 6 stage procedure meets test-driven development methodology:

  1. Writing a test case: Write an automated test case depending on the requirements.
  2. Running all the test cases: Running these automated test cases on the currently developed code.
  3. Developing the code for the test cases: Write the code for making the test case work as expected if the test case fails.
  4. Running test cases again: Running test cases again and checking if all the test cases developed so far are being used.
  5. Refactoring your code: Nevertheless, it is an optional step. It is important for retracting your code to make it more readable and reusable.
  6. Repeating steps 1 and 5 for new test cases: Repeating the cycle for other test cases until all the test cases are implemented.

Process of BDD

The process involved in BDD technology consists of 6 steps and is identifiable to that of TDD.

  1. Writing the behaviour of the application: The behaviour of an application is written in simple English-like language by the product owner of the business analysts or QA’s.
  2. Writing the automated scripts: Simple English-like language is then converted into programming tests.
  3. Implementing the functional code: Functional code underlines the behaviour is then implemented.
  4. Checking if the behaviour is successful: Running the behaviour and seeing if it is successful. It’s successful; you can move to the next behaviour and fix the errors in the functional code for achieving the application behaviour.
  5. Refactoring or organizing code: Refactor or organize your port to make it more readable and reusable.
  6. Repeating steps 1 and 5 for new behaviour: The steps should be repeated for implementing more behaviour in your application.

What’s the difference between TDD Vs BDD?

What are you testing for? I’d like to ask that a big question. Are you testing to understand the application’s behaviour? Or was the implementation more interested in you? When people ask the difference between BDD vs TDD, this question is often the main point of discussion. In TDD, you have a test method that will visit some States, but these tests may provide false results as the system evolves. But in BDD you are looking at the behaviour such as what will happen to the system under certain conditions.

Communication and feedback

In connectivity and feedback, BDD has the lead over TDD. Based upon the clear, straightforward English explanation of the behaviour in BDD, the customers can grasp the evaluations so that they can have input faster. These more open contact lines allow you to provide input on the testing and design of the app. In TDD, only qualified programmers can grasp the exam, which restricts contact with the broader public.

TDD vs. BDD again, but in simpler words

  1. BDD is easier when collaboration is quick and simple between the app developer and the product owner.
  2. TDD can not determine accurate actions, but with software code, you achieve better consistency.

Writing failing tests vs. Writing failing feature tests

As mentioned, the two methods begin with writing an unsuccessful test and take it out. Tests meet the developer and consumer requirements in BDD, but the test is designed to fulfil a developer-only and their code in TDD. As shown below, BDD operates on TDD, making it a simpler way to apply TDD. You should then never assume that BDD and TDD are two entities completely different.


It cannot be easy to choose between TDD Vs BDD. Some may contend that BDD is easier to detect glitches, while others may claim TDD has a higher code coverage. The implementation of both approaches, one to enhance the consistency of the code written by the creator and the other to promote the system’s behaviour as specified by the owner, is not harmful. No one is superior to the other technique. Deciding the approach to use would depend on the individual and the project team.

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