State Management Verification Matrix

Repository Boundary

This matrix verifies consumer behavior under Design Engineering. Shared quality gates own evidence admissibility. Passing a local model does not promote a domain or certify a consumer.

Reusable Method

Start with the selected pattern's invariant. Use controlled promises or an injected transport to choose completion order. Assert both displayed state and effect count or persistence payload; a screenshot alone cannot show which snapshot was saved.

Dimension	Required stress when applicable	Observable
Ordering	Start A/B; resolve B/A; stale error after new success	Current result, status, and error remain correlated
Mutation	Edit during save; normalized result; version conflict	Draft, baseline, submitted payload, revision
Duplication	Keyboard + pointer + another caller	Declared count and outcome sharing
Failure	Definitive rejection versus unknown write outcome	Draft retained; reconciliation before unsafe retry
Lifetime	Dispose; A → B → A; logout	No old-generation updates or scope leakage
Navigation	Back, Forward, reload, deep link, canceled departure	URL, visible controls, draft, and selection agree
Persistence	Corrupt version, wrong scope, unavailable storage, delayed restore	Valid defaults and preserved newer edits
Accessibility	Pending, error, empty, removed invoker	Announcements and logical focus recovery
Composition	Filter while deleting; edit during save-and-leave	Combined invariants survive interleaving

Executable Local Coverage

From a repository checkout, npm run test:state-management extracts and executes the standalone js block from each of the 12 pattern pages in an isolated Node process. The examples assert model outcomes for ownership, projections, selection, drafts, save snapshots, navigation decisions, stale completions, duplicate effects, optimistic recovery, URL parsing, identity generations, and restore validation.

The four recipes declare integration acceptance sequences; they are not runnable browser fixtures. Existing Interaction Lab is a separate prototype with its own evidence scope. New recipe acceptance remains unexecuted until adapted to a consumer.

Evidence Record

Record source revision, runtime, selected pattern/recipe, initial state, event sequence, submitted payload/effect count, expected state, actual state, and remaining limitations. Label unrun cases not_run; separate a model assertion from a browser observation and a server acknowledgement.

Opinionated Guidance

Use deterministic event ordering instead of sleeps. Test the stale failure path as well as stale success, and inspect cleanup/finally paths that can accidentally clear a newer pending operation.

Platform-Specific Guidance

Run browser navigation, focus, assistive-technology announcements, and storage failure checks in the actual target environment. Node URL and reducer examples cannot certify those integrations.

Unsupported Absolutes

A green model suite does not prove race freedom under every interleaving, real persistence, or accessibility. Synthetic transports do not establish server idempotency.

Verification Contract

For every consumer claim, identify a matching executed case or explicitly list missing evidence. Revisit the matrix when a real failure is not representable by its dimensions.

Source, License, And Attribution

Locally authored synthesis and examples. No upstream implementation is copied. These experimental contracts describe consumer-owned behavior; review when a failure, ownership change, or platform change invalidates an assumption.

IA Navigation

Parent: State Management. Next: Continue the state management route.