@ariada-org/diff-stub

NOT canonical — equality-only stub for OSS interoperability. This package matches findings strictly by fingerprint equality. It never emits near_duplicate classifications. For production CI you should use the canonical engine; otherwise false-positive «new» findings caused by trivial DOM drift will not be merged into pre_existing here.

Equality-only reference classifier for the differential accessibility CI gate. Use it for OSS interoperability checks, schema conformance tests, and self-hosted pipelines that do not need near-duplicate matching.

Open source under EUPL-1.2. Single workspace dependency: @ariada-org/diff-schema. Node 22 LTS or newer.

Install

npm install @ariada-org/diff-stub @ariada-org/diff-schema

Usage

import { classifyStub } from "@ariada-org/diff-stub";

const diff = classifyStub({
  headFindings: [
    {
      ruleId: "wcag2/1.1.1",
      jurisdictionTags: ["WCAG2.2-AA"],
      severity: "serious",
      selector: "main > img.hero",
    },
  ],
  baseFindings: [],
  diffId: "01HVABCDEF0123456789ABCDEFG",
  computedAt: new Date().toISOString(),
  head: { scan_id: "head-scan", scan_root_hash: "a".repeat(64) },
  base: { scan_id: "base-scan", scan_root_hash: "b".repeat(64) },
});

console.log(diff.engine_info.classifier); // → "stub"
console.log(diff.classification.new.length); // → 1

API

| Export | Type | Description | | --------------------------- | -------- | ------------------------------------------------ | | classifyStub | function | Equality-only classifier producing a DiffResult. | | STUB_CLASSIFIER_VERSION | constant | Stub version string. | | STUB_NOT_CANONICAL_BANNER | constant | Warning to surface in downstream UI / logs. |

When to NOT use this package

• You run the differential gate in a production CI pipeline where false-positive «new» findings from trivial DOM drift would block real merges.
• You need the canonical engine guarantees (deterministic near-duplicate matching, hierarchical policy resolution, exemption-with-DOM-invalidation).

Switch to the canonical engine via the GitHub Action's engine: canonical input, or invoke the SaaS API directly.

License

EUPL-1.2 for code; CC-BY-SA-4.0 for prose; CC0-1.0 for build config. See LICENSE and NOTICE.