Exploratory Testing is a software testing approach that is often used in the DevOps environment. It is an approach that allows testers to simultaneously learn, design tests, and execute them, providing a comprehensive understanding of the system's behavior and potential vulnerabilities. This approach is unique as it does not rely on predefined test cases or scripts, but rather on the tester's knowledge, experience, analytical/logical skills, creativity, and intuition.
The term 'Exploratory Testing' was coined by Cem Kaner in 1984, who defined it as a style of software testing that emphasizes the personal freedom and responsibility of the individual tester to continually optimize the quality of his/her work by treating test-related learning, test design, test execution, and test result interpretation as mutually supportive activities that run in parallel throughout the project.
Definition of Exploratory Testing
Exploratory Testing is a hands-on approach in which testers are involved in minimum planning and maximum test execution. The planning involves the creation of a test charter, a short declaration of the scope of a short (1 to 2 hour) time-boxed test effort, the objectives and possible approaches to be used. The test design and test execution activities are performed in parallel typically without formally documenting the test conditions, test cases or test scripts. This does not mean that other, more formal testing techniques will not be used. For example, the tester may decide to use boundary value analysis but will think through and test the most important boundary values without necessarily writing them down. Some notes will be written during the exploratory-testing session, so that a report can be produced afterwards.
The key skills needed in exploratory testing are observation, interpretation, analysis, synthesis, and creativity. The tester observes the behavior of the system, interprets the context, analyzes the observed behavior to identify potential problems, synthesizes a theory around the problem, and uses creativity to identify steps to reproduce it.
Characteristics of Exploratory Testing
Exploratory Testing is characterized by its focus on discovery, investigation, and learning. As such, it is a highly creative and intuitive process. This approach is contrasted with traditional testing methods that tend to be highly structured and require detailed test plans and test cases. Exploratory testing is a simultaneous process of test design and test execution all done in a very short amount of time. It is more about discovery and investigating the software to find where it breaks or behaves unexpectedly.
Another key characteristic of exploratory testing is its adaptability. The test design is not fixed and can be modified on the fly as the understanding of the system improves. This makes it a highly effective approach in situations where the system's behavior is not well understood or in situations where the test requirements are vague or incomplete.
Types of Exploratory Testing
There are several types of exploratory testing, each with its own unique approach and focus. The most common types include ad hoc testing, session-based testing, and freestyle testing. Ad hoc testing is a completely unstructured approach where the tester actively seeks out software flaws without any predetermined plan of action. Session-based testing, on the other hand, involves a structured approach where the tester creates a test charter that outlines the scope of testing for a specific session, but the actual test design and execution is still exploratory in nature.
Freestyle exploratory testing is a blend of the two previous types. It involves some level of planning and structure, but the test execution is largely unscripted and relies on the tester's intuition and experience. The tester may use a variety of test techniques such as boundary testing, equivalence partitioning, or error guessing, but the choice of technique and the specific test data used is determined as the test is being performed.
History of Exploratory Testing
The concept of exploratory testing has been around in the software testing industry for several decades, but it was only in the 1990s that it started to gain recognition as a distinct approach to testing. The term 'exploratory testing' was first coined by Cem Kaner, a professor of software engineering and a thought leader in the field of software testing. He defined exploratory testing as a style of software testing that emphasizes the personal freedom and responsibility of the individual tester to continually optimize the quality of his/her work by treating test-related learning, test design, test execution, and test result interpretation as mutually supportive activities that run in parallel throughout the project.
Since then, exploratory testing has been widely adopted in the software testing industry, and it has been recognized as a critical approach to uncovering software defects that may not be caught by traditional testing methods. The rise of agile development methodologies and DevOps has further highlighted the importance of exploratory testing as these approaches require rapid feedback and adaptability, which are inherent characteristics of exploratory testing.
Evolution of Exploratory Testing
Over the years, exploratory testing has evolved to adapt to the changing needs of the software development industry. The rise of agile development methodologies and DevOps has necessitated a shift from traditional, documentation-heavy testing approaches to more flexible and adaptive testing methods. Exploratory testing, with its emphasis on learning and adaptability, has proven to be a perfect fit for these new development paradigms.
Furthermore, the advent of new technologies such as artificial intelligence and machine learning has opened up new possibilities for exploratory testing. These technologies can be used to automate some aspects of exploratory testing, such as generating test data or identifying potential test scenarios, thereby enhancing the effectiveness of exploratory testing and freeing up testers to focus on more complex and creative aspects of testing.
Impact of Exploratory Testing on the Software Testing Industry
The impact of exploratory testing on the software testing industry has been profound. It has challenged the traditional view of testing as a rigid, structured process and has highlighted the importance of creativity, intuition, and adaptability in testing. It has also emphasized the role of the tester as a critical thinker and problem solver, rather than just a test executor.
Furthermore, exploratory testing has played a key role in the shift towards more agile and DevOps-centric development practices. By providing rapid feedback and adapting to changing requirements, exploratory testing has enabled teams to deliver high-quality software at a faster pace. It has also fostered a culture of collaboration and shared responsibility for quality, as it encourages everyone in the team to participate in testing activities.
Use Cases of Exploratory Testing
Exploratory testing is particularly useful in situations where the system's behavior is not well understood or the test requirements are vague or incomplete. It is also highly effective in uncovering defects that may not be caught by traditional testing methods. Some common use cases for exploratory testing include new feature testing, regression testing, and bug bash.
New feature testing is a common use case for exploratory testing. When a new feature is added to a software application, it is often not fully understood how it will interact with the existing features. Exploratory testing allows testers to quickly identify any unexpected behavior or inconsistencies.
Regression Testing
Regression testing is another common use case for exploratory testing. When changes are made to a software application, there is always a risk that these changes may inadvertently affect other parts of the application. Exploratory testing allows testers to quickly identify any unexpected side effects of these changes.
Furthermore, regression testing often involves a large number of test cases, and it may not be feasible to execute all of them in a limited time frame. Exploratory testing, with its focus on maximum test execution with minimum planning, allows testers to cover a wide range of functionality in a short amount of time.
Bug Bash
Bug bash is a collaborative testing activity where the entire team comes together to find and report bugs in a software application. This is a perfect scenario for exploratory testing as it allows everyone in the team to contribute their unique perspectives and insights, thereby increasing the chances of finding bugs.
During a bug bash, each team member is given a specific area of the application to test, and they are encouraged to use their creativity and intuition to find bugs. This not only helps in uncovering a wide range of bugs, but also fosters a culture of shared responsibility for quality.
Examples of Exploratory Testing
Let's consider a few specific examples to understand how exploratory testing works in practice. Suppose you are testing a new feature in a web application that allows users to upload and share photos. You start by exploring the feature, trying out different actions such as uploading different types of photos, sharing photos with different users, deleting photos, etc. As you explore, you observe the system's behavior and note any unexpected or inconsistent behavior.
For example, you might notice that the application crashes when you try to upload a very large photo. You analyze this behavior, form a theory about the potential problem (e.g., the application might not be handling large files correctly), and then design a test to reproduce the problem and confirm your theory. This is a classic example of exploratory testing in action.
Example in Regression Testing
Another example of exploratory testing can be seen in regression testing. Suppose a change has been made to the photo sharing feature in the above example, and you are tasked with testing this change. Instead of executing a predefined set of test cases, you decide to explore the feature, trying out different actions and observing the system's behavior.
As you explore, you might notice that the change has inadvertently affected another part of the application, such as the photo editing feature. You analyze this behavior, form a theory about the potential problem (e.g., the change might have introduced a bug in the photo editing feature), and then design a test to reproduce the problem and confirm your theory. This is another example of how exploratory testing can be used to uncover unexpected defects.
Example in Bug Bash
Finally, let's consider an example of exploratory testing in a bug bash. Suppose your team is conducting a bug bash for the entire web application. Each team member is given a specific area of the application to test, and they are encouraged to use their creativity and intuition to find bugs.
As you explore your assigned area, you might come across a bug that no one else has found. You analyze the bug, form a theory about its cause (e.g., it might be due to a race condition), and then design a test to reproduce the bug and confirm your theory. This is a great example of how exploratory testing can leverage the collective wisdom of the team to uncover a wide range of bugs.
Conclusion
In conclusion, exploratory testing is a powerful and versatile approach to software testing that emphasizes learning, creativity, and adaptability. It is particularly effective in situations where the system's behavior is not well understood or the test requirements are vague or incomplete. It is also highly effective in uncovering defects that may not be caught by traditional testing methods.
The rise of agile development methodologies and DevOps has further highlighted the importance of exploratory testing, as these approaches require rapid feedback and adaptability. Furthermore, the advent of new technologies such as artificial intelligence and machine learning has opened up new possibilities for exploratory testing, making it an exciting field to be in.