Deterministic test fixture rule | DevPrompt Lab

A repository instruction for repeatable tests that reveal regressions rather than environmental accidents.

Reusable content

Tests must create or load their own deterministic fixtures and clean up after themselves. Do not depend on production, shared developer records, current time without a frozen clock, external network services, or test ordering. Use explicit unique values and assert the behavior that matters. Database tests must verify the configured database name is an allowlisted test database before connecting. Keep fixtures small and representative.

Test framework: {{TEST_FRAMEWORK}}

Isolation rules: {{ISOLATION_RULES}}

How to use it

Add exact setup and cleanup commands for the repository once verified.

Example

Before connecting, require APP_ENV=test and DB_NAME=devpromptlab_test; otherwise exit nonzero before creating a PDO connection.