What Is BDD?

BDD comes from TDD, which is test driven development. It allows users to process multiple test data with minimal software code intervention, which helps to improve the reusability of code. It is a time-saving mechanism in software development and test automation.

By inheriting TDD, BDD also has all of these features and its own advantages.

  • The test scenarios are written in different files, which are called feature files.
  • Tests are written by focusing on user stories and system behavior in human readable  language.
  • Code is subject to be written differently in step definitions file i.e. Java, Python.

Why Use BDD Framework?

Before the BDD framework, everyone was using TDD. TDD works well in software development if testers are familiar with the framework used and have sufficient technical knowledge. However, this is not always the case.

BDD provides a way to bridge the gap between technical and non-technical teams, because test cases are usually written in simple text. The main advantages of BDD are fewer terms, clearer methods and easier to understand.

How to Implement the BDD Approach?

The test scenario should be written in easy to understand language, describing in detail the test, how to test the application and the application behavior that everyone can understand.

In this tutorial, we will focus on Cucumber – a software tool for BDD and will learn to practically implement it using its language – Gherkin.

Cucumber

Cucumber is a Behavior Driven Development (BDD) framework tool to write test cases.

Given – When – Then

  • Given: Some given context (Preconditions).
  • When: Some Action is performed (Actions).
  • Then: Particular outcome/consequence after the above step (Results).
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Sample Step Definition File

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Advantages Of Using BDD

Clarity of Scenarios

Gherkin language uses human readable text, focusing on the outcome of the product which is being tested/developed using BDD.

Because the function file separates the technical descriptions in the different step definition files of automated testers, it can help non-technical personnel understand automated testing easily. Any update can be implemented in a small discussion.

The readability of gherkin ensures the clarity of the scene for each user, which helps to build the right product.

Automation of Test Scenarios

Cucumber implementation in a BDD framework allows automation tester to easily initiate the scripting with the right approach. Easy language of cucumber scenarios helps them to understand the functionality in a better way.

Cucumber is a language-independent plugin as it is compatible with many programming languages E.g. Java, Python, etc.

Code Reuse in Framework

The Given-When-Then method allows testers to use the same steps multiple times in the function file, which helps to save time for automated testers.

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In the above two scenarios, we can conclude that “Given”, “When” and “Then” steps are reusable in the second scenario.

Parameterization in Feature File

A user can parameterize the gherkin steps in the feature file to obtain reusability in the file.

Like the sample scenarios above, by fill-in the test data in line or in separate data table, the parameters will passing to step definitions and executed in turn.

Conclusion

Behavior Driven Development is a very smart method in agile methodology. It is recommended that you use BDD to start development or testing, because BDD can provide a platform for you to use different technologies independently.

Cucumber is one of the best tools to help implement behavior driven development methods in software projects. This allows you to use many technologies, such as Java, python, Jython, and so on.

We hope this article can help you understand the basic knowledge of BDD, any questions please let us know :)