---
id: TST-COM-ORD-149
title: The Lambda participant client
kind: unit
product_area: commerce
module: orders
revision: 1
status: draft
source_sha:
  services-commerce: c8b66a98e2490617aec38ba5c8165dd9bd0a8f9b
repository: services-commerce
files:
  - modules/participants/tests/unit/client/lambda-participant-client.spec.js
implements:
  - ATS-COM-ORD-012-04
environment: mock
implementation_state: implemented
latest_result: not-run
latest_run_at: null
latest_run_ref: null
conformance: not-verified
estimated_minutes: 1
isolation: 'The suite owns its in-memory inputs, scripted responses and rendered component state.'
evidence:
  - provenance: test
    source: 'services-commerce:modules/participants/tests/unit/client/lambda-participant-client.spec.js'
    test_cases:
      - >-
        invokes the declared ARN synchronously with the wire envelope, the caller carrying the subject, and
        answers the parsed response
      - 'times out by the contract’s timeout for the operation, aborting the call: advise 5 s, prepare 10 s'
      - reports an SDK failure and a FunctionError as unavailable
      - 'reports an answer that is not JSON, or that the response schema refuses, as out of contract'
      - 'serves the other operations by their own schemas and timeouts: extend_hold, confirm_claims, fulfill'
scenario_coverage:
  - scenario: ATS-COM-ORD-012-04
    test_cases:
      - >-
        invokes the declared ARN synchronously with the wire envelope, the caller carrying the subject, and
        answers the parsed response
      - 'times out by the contract’s timeout for the operation, aborting the call: advise 5 s, prepare 10 s'
      - reports an SDK failure and a FunctionError as unavailable
      - 'reports an answer that is not JSON, or that the response schema refuses, as out of contract'
    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/participants/tests/unit/client/lambda-participant-client.spec.js'
  declared_by_test: 'the client, the contract''s schemas. Doubled: the SDK (`send`), a recording double.'
---

# The Lambda participant client

## Verification Boundary

The unit suite checks the named contract or helper with controlled inputs.

## What This Suite Proves

The registered cases check the Lambda participant client 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

Inputs and external responses are controlled in process; this suite establishes no deployed service behavior.

## Must Not Be Doubled

The named contract validation or component behavior under assertion must use its actual implementation.