Experience-based test techniques rely on the skills, intuition, and knowledge of testers to design and execute test cases. Unlike systematic techniques that focus on predefined rules and documentation, these methods leverage a tester’s expertise and past experience to identify potential defects and validate the software’s functionality.
Key Features
- Knowledge-Driven: Relies on the tester’s understanding of the domain, system, and common failure patterns.
- Flexibility: Adaptable to different contexts, especially where requirements are incomplete or ambiguous.
- Defect-Oriented: Focused on finding defects that may not be covered by formal test cases.
Types of Experience-Based Test Techniques
1. Error Guessing
- Involves anticipating potential defects based on the tester’s experience and intuition.
- Example: A tester might check for boundary value issues in a field accepting numerical input.
Advantages:
- Can quickly uncover common defects.
- Requires minimal documentation.
Limitations:
- Highly dependent on the tester’s skills and experience.
- May not provide systematic coverage.
2. Exploratory Testing
- Combines learning about the system with designing and executing tests in real time.
- Testers explore the application to find defects by following their instincts and observations.
Advantages:
- Ideal for new or complex systems.
- Uncovers defects in areas not anticipated by formal test cases.
Limitations:
- Difficult to replicate and document.
- Highly tester-dependent.
3. Checklist-Based Testing
- Uses predefined checklists to guide the testing process.
- Checklists are often derived from past experience, domain knowledge, or common defect patterns.
Advantages:
- Provides structure to experience-based testing.
- Easy to implement and adapt to different scenarios.
Limitations:
- May overlook defects not covered by the checklist.
- Effectiveness depends on the comprehensiveness of the checklist.
4. Fault Attacks
- Targets specific types of defects by using strategies designed to uncover those issues.
- Example: Testing a login feature by deliberately entering invalid credentials to ensure proper error handling.
Advantages:
- Focuses on high-risk areas.
- Proactively identifies vulnerabilities.
Limitations:
- Limited to the fault types being targeted.
- Requires deep knowledge of common failure modes.
When to Use Experience-Based Techniques
- Incomplete Requirements: When detailed requirements or specifications are unavailable.
- Tight Deadlines: During projects with limited time for test case design.
- Complex Systems: For systems that are dynamic or difficult to document.
- Risk Areas: When focusing on areas with a history of defects or high failure potential.
Best Practices
- Combine with Formal Techniques: Use experience-based methods alongside systematic techniques for comprehensive coverage.
- Leverage Domain Expertise: Involve testers with domain-specific knowledge.
- Document Findings: Maintain records of defects found and approaches used to inform future testing efforts.
- Iterate and Refine: Continuously improve techniques based on past testing results.