Test Case Design – Core Concepts & Best Practices What is a Test Case? A test case is a documented scenario used to verify that a system functions as expected. It defines: What to test (functionality or feature) Inputs, steps, and expected outcomes ✏️ Parts of a Test Case: Test Case ID: Unique identifier (e.g., TC_API_001) Title/Description: What it covers (e.g., "Verify successful login with valid credentials") Preconditions: What must exist before testing (e.g., user account created) Test Steps: Step-by-step actions Test Data: Inputs needed Expected Result: The correct output/result Actual Result: (filled after execution) Status: Pass/Fail Priority/Severity (optional) 📘 Types of Test Cases: ✅ Positive (valid input, expected behavior) ❌ Negative (invalid input, error handling) ⚠️ Edge/Boundary (min/max values, limits) 🔁 Regression (previous bugs/features) 🔄 Reusable/Common scenarios (login, logout, form validation) 📌 Techniques for Test Design: Equivalence Partitioning: Group inputs with similar behavior Boundary Value Analysis: Test values at the edge (e.g., 0, 1, max int) Decision Tables: Logical conditions and expected actions State Transition Testing: Validate behavior based on state changes 🛠️ Test Data Considerations Prepare relevant data before test Use random or fake data generators when needed (e.g., Faker, Mockaroo) Clean up test data after execution if needed 🧠 Test Case Writing Tips Be clear and concise Use consistent formats Always define expected results Keep tests independent Use ID conventions (TC_UI_01, TC_API_02) Prioritize based on risk and impact ✅ Best Practices for Test Case Management Use a test case management tool (e.g., TestRail, Zephyr, XRay) Keep test cases version-controlled Link test cases to requirements or user stories Automate high-priority/critical cases Maintain traceability