Mastering BDD Scenarios: Declarative, Imperative, and Hybrid Writing Styles Explained

Behavior Driven Development (BDD) is a powerful approach to software development that bridges the communication gap between developers, testers, and business stakeholders. One of the critical aspects of BDD is writing clear and effective scenarios.

In this blog, we’ll dive into the three main styles of BDD scenario writing: Declarative, Imperative, and Hybrid. We’ll explore their differences, provide examples, and suggest images to enhance your understanding.

1. Declarative Style

The declarative style focuses on the “what” rather than the “how.” It describes the desired behavior of the system without detailing the implementation steps.

This style promotes readability and maintainability, making it easier for non-technical stakeholders to understand the scenarios.

Example:

Feature: User Profile

  Scenario: View profile details
    Given a user is logged in
    When they navigate to the profile page
    Then they see their profile details

2. Imperative Style

The imperative style emphasizes the “how” by providing detailed, step-by-step instructions. This style can be beneficial for scenarios where the exact steps are crucial for understanding the behavior.

Example:

Feature: User Profile

  Scenario: View profile details
    Given a user enters their username
    And enters their password
    And clicks the "Login" button
    When they click on the "Profile" link
    Then they see their profile details

3. Hybrid Style

The hybrid style combines elements of both declarative and imperative styles.

It aims to balance clarity and detail, making it suitable for complex scenarios that require both high-level understanding and specific actions.

Example:

Feature: User Profile

  Scenario: View profile details
    Given a user is authenticated
    When they navigate to the profile page
    Then they see their profile details including:
      | Field    | Value          |
      | Username | johndoe        |
      | Email    | john@example.com |

Conclusion

Choosing the right BDD scenario writing style is essential for clear communication and effective automation.

The declarative style promotes readability, the imperative style provides detailed instructions, and the hybrid style offers a balance of both.

By understanding and applying these styles, you can enhance your BDD scenarios and create a more robust automation framework.

Happy testing!