How do you understand the process of designing test cases?

The process of test case design is a systematic approach to creating and documenting a set of input data, preconditions, expected results, and postconditions for a specific test scenario. The goal is to verify a particular functionality or requirement of the system.

Stages of the process:

1. Requirement Analysis: Studying documentation (User Stories, Specification), defining the testable functionality, identifying explicit and implicit requirements.
2. Test Condition Identification: Highlighting specific conditions or execution paths that need to be tested. Based on requirements and risk analysis.
3. Test Design Techniques: Applying techniques to select the optimal and effective set of test data and scenarios.
   • Equivalence Partitioning
   • Boundary Value Analysis
   • Decision Tables
   • State Transition Diagrams
   • Pairwise Testing
   • Exploratory Testing (unstructured approach at the design stage)
4. Test Case Specification: Creating detailed test cases based on selected conditions and techniques.
   • Test case ID
   • Name
   • Priority
   • Type (Function, UI, Performance, etc.)
   • Description/Purpose
   • Preconditions
   • Test Steps
   • Expected Result
   • Postconditions/Cleanup
5. Test Case Review: Reviewing test cases with colleagues for completeness, accuracy, clarity, and compliance with requirements.
6. Test Case Management: Storing and organizing test cases in a test management system (TMS), such as TestRail, Zephyr, Xray.

Thus, test case design is not just writing steps but a comprehensive activity aimed at ensuring quality coverage of requirements using an optimal set of tests.