mercadodevida/work/artifacts/F-019/implementer.md

Implementer — F-019 Promotions v1

Summary

Implemented server-side promo codes with percent/fixed-amount rules, validity/usage validation, cart promo-code application, and recalculated discounts during cart reads.

Files changed

• project/migrations/014_promotions.js
• project/src/modules/promotions/**
• project/src/modules/cart/**
• project/src/app/build-app.ts
• project/src/app/tests/promotions.itest.ts

Acceptance evidence

• AC1 valid promo: promotions.itest.ts applies SAVE10; cart returns server-calculated discount and reduced total.
• AC2 expired/exhausted promo: promotions.itest.ts verifies HTTP 422 for expired and usage-limit exhausted codes.
• AC3 client-supplied discount ignored: promo and cart schemas strip unknown discount fields; cart stores only selected promo code, not discount amount.
• verify.sh: passed.

Commands run

• cd project && npm run lint — passed
• cd project && npm run typecheck — passed
• cd project && npm run build — passed
• cd project && npm test — passed
• cd project && TEST_DATABASE_URL='postgres://mdv:mdv_dev_only@localhost:5432/mdv_test' npm run test:integration -- promotions.itest migrations.itest — passed; 11 files, 44 tests
• ./scripts/verify.sh — passed

Notes

• No stacking in v1: one promo_code per cart.
• Usage count is validated for exhaustion; consumption/increment can be tied to checkout/order completion in a later feature.