React migration cleanup and rollback

Run cleanup once each migrated React state owner/slice passes tests and affected UI flows have been verified. Remove old providers, custom hooks, context modules, external-store adapters, and pass-through wrappers unless they are explicitly documented compatibility shims.

React cleanup targets React state owner modules such as providers, hooks, context files, and old external store adapters.

Remove old owners and imports

Verify zero references with targeted searches for the old owner path, provider, hook names, and context names. Examples:

• grep -rn "CartProvider" src/ --include="*.ts" --include="*.tsx"
• grep -rn "useCartContext" src/ --include="*.ts" --include="*.tsx"
• grep -rn "from .*cart-context" src/ --include="*.ts" --include="*.tsx"

Do not leave a one-line re-export or delegate-only wrapper that keeps the old module path alive. Remove it, inline it, or document it as a temporary shim with a sunset condition.

Cleanup evidence

type ReactCleanupEvidence = {
  migratedSlice: string;
  removedOwners: string[];
  remainingOldPathMatches: string[];
  passThroughWrappers: string[];
  documentedShims: Array<{ path: string; removalCondition: string }>;
  verification: string[];
};

export const cartCleanupEvidence: ReactCleanupEvidence = {
  migratedSlice: "cart",
  removedOwners: ["src/cart/CartProvider.tsx", "src/cart/useCartContext.ts"],
  remainingOldPathMatches: [],
  passThroughWrappers: [],
  documentedShims: [],
  verification: ["cart reducer tests", "cart saga tests", "cart component tests"],
};

Compatibility shim requirements

/**
 * Compatibility shim for plugin-cart@2.x until plugin-cart >= 3.0 is required.
 * New callers must import from "../store/cart/cart-selectors".
 */
export { selectCartTotal } from "../store/cart/cart-selectors";

Every shim must state the compatibility consumer, the removal condition, and the new import path. Verifier output should say either “no pass-through wrappers” or list each documented shim.

Rollback recipe

If the migrated slice regresses:

1. Restore the old provider/hook/context files from git history.
2. Remove the new reducer map entry from the ReactStore constructor.
3. Remove the matching reactStore.runSaga(sagaFn) startup call.
4. Restore affected component imports.
5. Re-run tests for the restored React path.

Final checklist per slice

• Reducer registered in the ReactStore reducer map.
• App saga started after reactStore.init() when the slice has side effects.
• Components/custom hooks use direct selector signals first; any .useValue(...args) reads are documented as necessary plain-value fallbacks.
• Handlers/tests use .select(reactStore.state, ...args).
• Old providers/hooks/context/external-store adapters removed or documented as compatibility shims.
• Targeted searches confirm zero stale imports.
• Tests and affected UI checks pass.

Bad: deleting while consumers still import old context

// BAD: consumersStillImportingOldPath must be empty before deleting the provider.
export const badCleanupPlan = {
  oldOwnerPath: "src/cart/CartProvider.tsx",
  consumersStillImportingOldPath: ["HeaderCartButton.tsx", "Checkout.tsx"],
  deleteOldOwnerNow: true,
};