---
id: TST-COM-ORD-021
title: The preprocessing extension through preview and placement
kind: api-lifecycle
product_area: commerce
module: orders
revision: 1
status: draft
source_sha:
  services-commerce: c8b66a98e2490617aec38ba5c8165dd9bd0a8f9b
repository: services-commerce
files:
  - modules/checkout/tests/e2e/checkout-preprocessing.e2e.spec.js
implements:
  - ATS-COM-ORD-003-10
environment: local
implementation_state: implemented
latest_result: not-run
latest_run_at: null
latest_run_ref: null
conformance: not-verified
estimated_minutes: 2
isolation: The suite creates its own test workspace records and removes them using the fixture cleanup.
evidence:
  - provenance: test
    source: 'services-commerce:modules/checkout/tests/e2e/checkout-preprocessing.e2e.spec.js'
    test_cases:
      - >-
        previews the checkout as the extension answered it: two t-shirts, the dropped mug gone, a bundled mug
        added
      - >-
        prices what the checkout now holds: two t-shirts and the mug, the bundle coupon taking $2.00 off the
        mug
      - 'sets the order fields the extension is allowed to set: the coupon codes and the metadata'
      - 'records one checkout.preprocessed event naming the extension, the mode and what changed'
      - 'finds nothing to change on a second preview, and writes no second event'
      - >-
        runs the point again at placement, finds nothing to change, and places the bundled lines at the
        previewed prices
      - >-
        applies the answer at placement when the checkout was never previewed, recording the placement-mode
        event
      - >-
        refuses the preview and the placement with EXTENSION_UNAVAILABLE (503) when the required extension
        answers outside its contract, placing nothing
      - 'skips an optional extension that fails, prices the checkout as it is, and tells the trail'
scenario_coverage:
  - scenario: ATS-COM-ORD-003-10
    test_cases:
      - >-
        previews the checkout as the extension answered it: two t-shirts, the dropped mug gone, a bundled mug
        added
      - >-
        refuses the preview and the placement with EXTENSION_UNAVAILABLE (503) when the required extension
        answers outside its contract, placing nothing
      - 'skips an optional extension that fails, prices the checkout as it is, and tells the trail'
    scope: >-
      The cited cases exercise the scenario’s listed fixture outcomes; this register makes no verified
      conformance claim.
dependency_evidence:
  provenance: test
  source: 'services-commerce:modules/checkout/tests/e2e/checkout-preprocessing.e2e.spec.js'
  declared_by_test: >-
    the composed handler, the routes, the workflows, the stub participant, the engine, the invoker, the
    failure policy, the persistence services and PostgreSQL. Doubled: the signing key pair, the other
    services' tables (local stand-ins), the extensions (the fixture registry the running macroservice uses
    today).
---

# The preprocessing extension through preview and placement

## Verification Boundary

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

## What This Suite Proves

The registered cases check the preprocessing extension through preview and placement 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.