Promotion codes: what is refused and what is never a 500 (R-4, end to end)

Verification Boundary

The suite drives the composed local API dispatcher and its registered routes.

What This Suite Proves

The registered cases check promotion codes: what is refused and what is never a 500 (R-4, end to end) with their fixture records and assertions. Scenario bindings name only the examples those cases exercise.

What It Does Not Prove

A registered file supplies no run result or verified conformance by itself. Local fixtures do not establish deployed cross-service behavior or complete browser journeys.

Real Dependencies and Test Doubles

PostgreSQL and the exercised Commerce persistence or workflow code are real. Remote service records, clocks and transports follow the suite’s fixtures.

Must Not Be Doubled

The database constraints, role restrictions, locks and transactions exercised by this suite must use PostgreSQL.