Prove Behavior

A valid test distinguishes a required behavior or contract from a plausible, material defect. It continues to pass after an internal refactor that preserves that behavior or contract.

Steps

Step 1 — Name the evidence

State:

• the required behavior;
• its accepted source: a requirement, acceptance criterion, contract, known bug, or recorded observation whose preservation is required;
• one plausible defect the evidence must detect;
• the meaningful harm that defect would cause.

Meaningful harm includes a broken user task, violated contract, corrupt data, weakened security or accessibility, or a repeated costly failure.

If no accepted source, named defect, or meaningful harm exists, choose no automated test.