Behavior Driven Testing | What it is , How to Do & Tools

In the rapidly evolving world of software development, Behavior Driven Testing (BDT) has emerged as a pivotal methodology, aligning technical requirements with business objectives. A study by the Standish Group reveals that only 29% of IT project implementations are successful, with failures often attributed to poor communication and misunderstood requirements. BDT addresses these challenges head-on. For instance, companies like ING, a global financial institution, have successfully implemented BDT, resulting in a significant improvement in collaboration between developers and business stakeholders, thereby enhancing the quality and efficiency of their software products. This real-world success story exemplifies the transformative impact of BDT in bridging the gap between technical execution and business vision.

What is Behavior Driven Development?

Behavior Driven Development (BDD) is an agile software development process that encourages collaboration between developers, QA, and non-technical or business participants in a software project. It focuses on obtaining a clear understanding of desired software behavior through discussion with stakeholders. This approach emphasizes the importance of mutual understanding and aims to create software that fulfills specific business needs. For a deeper insight into BDD, explore TestSigma’s article on Behavior Driven Development with Gherkin.

What is the Purpose of BDD?

The primary purpose of BDD is to improve communication among project stakeholders so that developers, testers, and business representatives have a clear understanding of the project’s goals. BDD aims to help teams focus on delivering key functionalities based on the end-user’s needs, enhancing the overall quality and effectiveness of the software being developed.

What is BDD Testing?

BDD Testing is a part of the Behavior Driven Development process where testing is based on the behavior of the software under different conditions. It involves writing tests in a natural language that non-programmers can read. BDD Testing bridges the gap between the technical language of the code and the domain language of the business. For an in-depth look at BDD Testing, visit Testsigma’s blog on Cucumber vs. TestSigma.

When to Use Behavior-Driven Testing?

Behavior-Driven Testing is particularly useful in complex projects where clear communication between technical and non-technical team members is crucial. It is best employed when the project requires frequent feedback from stakeholders and when ensuring that all development work aligns closely with business objectives.

When to Not Use Behavior-Driven Testing?

While BDD is highly beneficial in many scenarios, it might not be suitable for projects with very tight deadlines due to the initial time investment needed to establish clear communication and write test scenarios. It may also be less effective in small projects where the development team already has a clear understanding of the requirements.

Alternatives to Behavior Driven Testing and Related Tools

While Behavior Driven Testing (BDT) is a powerful approach, there are alternative methodologies in software testing that cater to different project needs:

Test-Driven Development (TDD):

TDD focuses on writing tests before developing the actual code. This method is ideal for projects where functional accuracy is paramount.

Acceptance Test-Driven Development (ATDD):

ATDD involves team members from different backgrounds (development, testing, and business) collaborating to write acceptance tests before the software is developed.

Exploratory Testing:

This is a more ad-hoc approach where testers dynamically design and execute tests based on their understanding and exploration of the software.

Scriptless Testing:

An approach that simplifies test automation by removing the need to write test scripts. Tools like Testsigma implement scriptless testing to make test automation more accessible. For more on this approach, see Testsigma’s article on Scriptless Testing.

Each of these methodologies, including BDT, has its specific context where it excels, and the choice largely depends on the project requirements and team expertise.

What Are the Principles of Behavior Driven Development?

The principles of Behavior Driven Development (BDD) are centered around effective communication and collaboration. Key principles include:

Clear Communication:

BDD emphasizes clear, jargon-free communication using a language that is understandable to all stakeholders.

Customer-Centric Approach:

It focuses on delivering features that provide real value to the end user.

Collaboration:

BDD encourages active collaboration between developers, testers, and business stakeholders to define requirements and understand business objectives.

For a detailed exploration of BDD principles, Testsigma offers insights in their blog on Behavior Driven Development with Gherkin.

BDD Process

The BDD process typically involves the following steps:

Discovery:

Collaboratively discussing and capturing requirements in a format everyone understands. Describe the behavior.

Formulation:

Converting those requirements into a formalized format, often using Gherkin syntax.

Automation:

Automating the acceptance criteria as tests, often with tools like Cucumber or Testsigma.

Execution:

Running these automated tests to validate that the software meets the defined criteria.

Refinement:

Continuously refining and updating the tests as the understanding of the requirements evolves.

Prerequisites for Implementing BDD

Before embarking on Behavior Driven Development (BDD), certain prerequisites should be in place:

Clear Understanding of Business Goals:

A deep understanding of what the business aims to achieve with the software is crucial for effective BDD.

Collaboration Tools:

Tools that facilitate communication and collaboration among cross-functional teams are essential.

Skilled Team Members:

Team members should be well-versed in BDD principles and comfortable with tools like Gherkin for writing behavior specifications.

Integration with Existing Processes:

BDD should seamlessly integrate with the existing development, testing, and deployment processes.

How Behavior Driven Development Works?

Behavior Driven Development works by following these steps:

Define Behavior:

Start with defining the behavior of the application in simple language that all stakeholders can understand.

Write Feature Files:

Document these behaviors in feature files using a language like Gherkin.

Develop Step Definitions:

Create step definitions that bridge the gap between the language in the feature files and the code.

Automate Tests:

Use tools like Cucumber or Testsigma to automate the execution of these behaviors as tests

Refine and Iterate:

Continuously refine and iterate on behaviors as the project progresses and requirements evolve.

How to Do BDD Testing?

Manual BDD Testing

Manual BDD Testing involves:

1. Reviewing Feature Files: Understanding the features and behaviors described in the feature files.
2. Exploratory Testing: Conducting exploratory tests based on these behaviors to ensure they align with the business objectives.
3. Feedback Loop: Providing feedback to refine the feature files and ensure they accurately reflect the desired behavior.

Automated BDD Testing with Testsigma

Testsigma allows you to automate tests in simple English, thus no need to write specific feature files and then coding them. The automated tests are themselves easy to understand as they are written in simple English.

In addition, Testsigma is a complete test automation platform where you can automate tests for web, mobile, desktop and APIs, from the same place. The tests can be authored, executed and reported all via Testsigma and can be integrated easily within your CICD pipelines too.

Behavior-Driven Testing Advantages

Here are four advantages of using Behavior-Driven Testing:

Enhanced Collaboration:

BDT promotes stakeholder collaboration, including testers, developers, product owners, and business analysts. By using a common language and format (often Gherkin syntax), BDT allows stakeholders to collaborate effectively on defining requirements and acceptance criteria.

This collaborative approach ensures that everyone understands the expected software behavior, leading to more accurate testing and higher-quality outcomes.

Clear and Understandable Tests:

BDT encourages the creation of clear, concise, and understandable tests written in a natural language format. Tests are written in a user-centric way, using scenarios and examples that reflect real-world usage. This makes the tests more accessible to non-technical stakeholders, such as product owners and business analysts, who may not have a deep technical background.

Clear and understandable tests help ensure that everyone involved in the testing process can easily interpret and validate the expected behavior of the software.

Early Detection of Requirements Issues:

BDT facilitates the early detection of requirements issues and ambiguities by encouraging collaborative discussions during the specification phase. By writing scenarios and examples in Gherkin syntax (Given-When-Then), stakeholders can identify potential gaps, inconsistencies, or misunderstandings in the requirements before development begins.

This early feedback loop helps prevent costly rework and reduces the risk of delivering software that does not meet the intended requirements.

Automated Test Execution:

BDT enables the automation of tests written in Gherkin syntax using tools like Cucumber, SpecFlow, or Behave. Automated tests can be executed repeatedly throughout the development lifecycle, providing rapid feedback on the behavior of the software as it evolves.

Automated BDT tests serve as living documentation that validate the correctness of the software against the defined behavior, helping teams maintain confidence in the quality of their codebase and facilitating continuous integration and delivery practices.

Limitations of BDD Testing

Here are several limitations of BDD testing:

Requires Significant Upfront Investment:

BDD testing requires an initial investment of time and effort to define clear and comprehensive specifications in Gherkin syntax. This can be challenging, especially for complex systems or projects with evolving requirements.

Writing and maintaining detailed feature files can be time-consuming and require ongoing stakeholder collaboration.

Dependency on Stakeholder Involvement:

BDD relies heavily on collaboration and active involvement from stakeholders, including product owners, business analysts, and developers. If stakeholders are not fully engaged or lack domain knowledge, it can lead to incomplete or inaccurate specifications.

Limited stakeholder availability or participation can hinder the effectiveness of BDD testing.

Potential for Misinterpretation:

Despite efforts to write clear and understandable specifications, there is still a risk of misinterpretation or ambiguity.

Different stakeholders may have varying interpretations of the same scenario or example, leading to discrepancies in understanding and implementation. Misinterpretation can result in inaccurate tests and false positives/negatives.

Complexity of Automation:

While BDD promotes the automation of tests written in Gherkin syntax, automating complex scenarios can be challenging. Writing and maintaining automated tests requires technical expertise and familiarity with automation tools like Cucumber, SpecFlow, or Behave.

Maintaining synchronization between feature files and automation code can also be cumbersome, especially as requirements evolve.

Overhead of Maintenance:

As the software evolves and requirements change, feature files and automated tests must be updated accordingly. Maintaining synchronization between feature files, automated tests, and the application code requires ongoing effort and can be prone to errors.

Without proper maintenance, feature files and automated tests can become outdated and lose their effectiveness.

Limited Support for Non-UI Testing:

BDD testing primarily focuses on testing the behavior of user interfaces (UI) through scenarios written in Gherkin syntax. While it can be adapted for testing other application layers, such as APIs or backend services, BDD tools and frameworks are often optimized for UI testing.

Testing non-UI components may require additional effort and workaround solutions.

Difficulty in Testing Non-Deterministic Behavior:

BDD testing may need help to handle scenarios involving non-deterministic behavior, such as time-sensitive operations or external dependencies (e.g., network connectivity).

Writing automated tests for such scenarios can be challenging, as it may require mocking or stubbing external dependencies, which can introduce complexity and reduce test reliability.

What Are the Common BDD Challenges I Might Meet?

Common challenges in implementing BDD include:

Miscommunication between Teams:

Even with BDD’s focus on communication, misunderstandings can still occur, especially between technical and non-technical stakeholders.

Complexity in Test Maintenance:

As the project evolves, maintaining and updating BDD tests can become complex.

Integration with Existing Processes:

Seamlessly integrating BDD into existing development and testing workflows can be challenging.

Initial Learning Curve:

Teams new to BDD may face a learning curve in understanding and implementing the methodology effectively.

Time Investment for Setup:

Setting up BDD requires time and effort, especially in writing comprehensive feature files.

Over-Reliance on Tools:

There’s a risk of over-reliance on specific tools for BDD, which can limit flexibility.

How Can I Avoid Common Mistakes in BDD?

To avoid common mistakes in BDD:

Regular Training:

Ensure regular training sessions for team members on BDD principles and practices.

Continuous Collaboration:

Foster a culture of continuous collaboration and open communication across all teams.

Iterative Approach:

Take an iterative approach to BDD implementation, starting small and gradually expanding as the team becomes more comfortable with the process.

BDD Best Practices

Behavior Driven Development, when executed with best practices in mind, can significantly enhance the effectiveness of software development projects. These practices ensure that BDD is not just a process but a robust framework that adds value to the entire development lifecycle.

Clear and Concise Language:

Writing in simple, understandable language in feature files is essential for clear communication among all stakeholders, regardless of their technical expertise.

Regular Refinement Sessions:

Holding regular sessions to review and refine feature files helps keep them up-to-date with project changes and ensures ongoing relevance.

Incorporate Feedback:

Actively incorporating feedback from developers, testers, and business stakeholders helps to improve and evolve the BDD process continually.

Balance between Automation and Manual Testing:

While automation is integral to BDD, balancing it with manual exploratory testing ensures comprehensive coverage, including scenarios that automated tests might not address.

How Do BDD and Test Management Interrelate?

The synergy between Behavior Driven Development and test management is a key factor in the success of software projects. This interrelation enhances both the efficiency and effectiveness of the testing process within the development lifecycle.

Structured Approach:

BDD offers a structured approach to defining test scenarios, aiding in more organized and efficient test management.

Enhanced Traceability:

Improved traceability from requirements to tests in BDD ensures effective tracking of coverage and progress, a boon for test managers.

Efficient Test Planning:

The clear definition of expected behaviors and outcomes in BDD leads to more efficient planning and execution of tests.

BDD and Agile

Behavior Driven Development aligns seamlessly with Agile methodologies, enhancing the Agile principles of collaboration, quick feedback, and adaptive planning.

Enhancing Collaboration:

The collaborative nature of BDD fits perfectly with Agile’s focus on teamwork, bringing together developers, testers, and business stakeholders.

Facilitating Quick Feedback:

Agile thrives on rapid feedback loops, and BDD supports this by enabling quick verification of behaviors through short, iterative development cycles.

Promoting Adaptive Planning:

The iterative approach of BDD complements Agile’s adaptive planning and development methodologies, allowing for flexibility and responsiveness to change.

Behavior Driven Development Tools

Selecting the right tools is critical in the effective implementation of Behavior Driven Development. These tools not only facilitate the BDD process but also integrate it smoothly into the broader software development workflow.

Cucumber:

Popular for writing and executing feature files in Gherkin, Cucumber is a staple in many BDD workflows.

Specflow:

A .NET-centric tool, SpecFlow is similar to Cucumber but tailored for integration with the .NET ecosystem.

Testsigma:

Providing a unified platform, and an approach to author test cases in simple English, Testsigma simplifies the implementation of behaviour-driven testing.

Behavior-Driven Development Tool Selection

Choosing the right BDD tool can significantly impact the effectiveness of the BDD process in your project. The decision should be guided by a thorough assessment of project needs, team capabilities, and integration requirements.

Project Requirements:

The tool should align with the specific requirements of your project, considering aspects like language and framework compatibility.

Team Expertise:

It’s important to choose a tool that matches the skill set of your team to ensure smooth adoption and effective use.

Integration Capabilities:

Opt for tools that can seamlessly integrate with your existing development and testing environment to streamline workflows.

Conclusion 

In conclusion, Behavior Driven Development (BDD) stands as a pivotal methodology in modern software development, harmonizing communication between technical teams and business stakeholders. It enhances clarity, ensures alignment with business objectives, and elevates the overall quality of the software development process. 

Despite its challenges, the successful implementation of BDD, especially when coupled with tools like Testsigma, can lead to significant improvements in both development efficiency and outcome. Embracing BDD signifies a commitment to collaborative and customer-centric development, a cornerstone in today’s fast-paced, quality-driven software industry.

Frequently Asked Questions