Test Strategy

Purpose

Select tests that prove an observable requirement at the lowest sufficient cost. Candidate discovery does not create an obligation to implement every technically valid test.

Selection Process

For each acceptance criterion that may require integration or E2E proof:

1. Name the observable boundary: Identify the interaction, persisted effect, process, or user journey that must be proven.
2. Check existing proof: Reuse or extend an established test when it already observes the required behavior.
3. Select the narrowest level:
   • use a unit or local check for isolated behavior;
   • use integration when the requirement depends on a named component, persistence, or process boundary;
   • use E2E only when the complete journey is itself the requirement.
4. Compare cost: Consider setup, execution time, brittleness, maintenance, and diagnostic value using repository evidence rather than fixed universal scores.
5. Retain necessary proof: Select a test only when a cheaper boundary cannot establish the required behavior or protect an accepted contract.