Files
whynot-design/adapters/lit
tegwick 552d8fe926 feat(adapter): Lit component scaffold + drift report (WHYNOT-WP-0002 T07)
Extend make adapt-lit beyond tokens: parse src/elements/*.js, compare each IR
component contract against its <wn-*> element, and emit per-component drift
reports + a machine roll-up (adapters/lit/drift/), with write-once stubs
(adapters/lit/stubs/) for genuinely new components. Never overwrites
hand-authored sources.

- Severity split: actionable drift (prop-missing, attribute-mismatch,
  variant-axis-missing, tag-mismatch) gates with exit 3; non-portable + prop-extra
  are informational (the IR carries React style/onClick; Lit is richer than the
  minimal designbook) and don't gate.
- Current state: 7 ok, 3 actionable drift for human triage — PipelineStrip
  (wn-pipeline-strip vs hand-authored wn-pipeline rename), PageHeader (actions is
  a slot, not a prop), Sidebar (IR 'current' axis absent on the element).
- _report.json reuses generatedAt/irRef when drift is unchanged (no git churn).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-06-30 09:03:22 +02:00
..

Lit reference adapter

Projects the technology-neutral IR (ir/) onto the Lit stack. This is the reference adapter — the contract every stack adapter implements lives in adapters/ADAPTER_CONTRACT.md.

Run it with make adapt-lit (adapters/lit/adapt.mjs).

What it does

Per the contract, an adapter is scaffold + drift-detect, never a rewrite:

Concern Behaviour Status
Tokens Fully generated from ir/tokens.json into the :root block of src/styles/colors_and_type.css, between @generated tokens markers. Deterministic — re-running with an unchanged IR is a byte-identical no-op. The hand-authored type/utility CSS after the block is preserved. done (T06)
New component Generate a <wn-*> Lit stub from the IR contract's prop→attribute map + a behaviour TODO. T07
Changed component Emit a drift report (adapters/lit/drift/<Name>.md) — never overwrite the hand-authored element. T07

Directionality

One-way: React → ir/ → Lit. This adapter is downstream of the IR; it never writes back to ir/ or to the React designbook. A change to the shared language is made in Claude Design and re-propagated (make designbook-pull && make ir && make adapt-lit). See .claude/rules/designbook-propagation.md.

Token regeneration is a visual change

Because tokens are fully generated, regenerating them can change rendered appearance when the canonical React designbook has moved (e.g. a font-stack or colour change). That makes the Playwright baselines diverge by design — it is a human review point, not an error:

make adapt-lit          # regenerates tokens
pnpm test:visual        # will fail where appearance changed
# review the change, then if correct:
pnpm test:visual:update # accept new baselines

Never run test:visual:update to silence a token change without reviewing it — that defeats the parity gate (T08).

Exit codes

0 ok · 2 usage/config · 3 drift detected · 4 parity failure · 5 internal.