@types/react 19.2.18: useActionState

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify useActionState in pkg:npm/%40types/react@19.2.18
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/%40types/react@19.2.18
Demonstrate these symbols/APIs:
  - useActionState
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - packageManager: npm@10.9.8
  - runtime: node@22.23.2

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

{"case":{"caseId":"case:sha256:556ccf5ddc1ba85b0bb135f2181a7efd314379dd254733b02e5d7655090d713a","constraints":{"executionContext":"node"},"contract":["package manifest specifies index.d.ts type entry, ts5.0 typesVersions fallback, and TypeScript 5.6 compatibility","declares useActionState hook overload for action without payload returning state, parameterless dispatch, and isPending","declares useActionState hook overload for action with payload returning state, parameterized dispatch, and isPending","supports Awaited\u003cState\u003e unwrapping for synchronous and Promise-returning action return types with named tuple structure","declares optional permalink string parameter across all useActionState overloads","provides identical useActionState hook signatures in TypeScript 5.0 compatibility fallback declaration ts5.0/index.d.ts"],"goal":"verify useActionState in pkg:npm/%40types/react@19.2.18","kind":"HOW","packages":["pkg:npm/%40types/react@19.2.18"],"schemaVersion":1,"symbols":["useActionState"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","executionContext":"node","language":"javascript","libc":"glibc","libcVersion":"2.39","moduleSystem":"cjs","os":"linux","osVersionBucket":"24","packageManager":"npm","packageManagerVersion":"10.9.8","runtime":"node","runtimeVersion":"22.23.2","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/%40types/react@19.2.18"],"schemaVersion":1,"subject":"pkg:npm/%40types/react@19.2.18","symbols":["useActionState"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-types-react-use-action-state",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-types-react-use-action-state",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "@types/react": "19.2.18"
      }
    },
    "node_modules/@types/react": {
      "version": "19.2.18",
      "resolved": "https://registry.npmjs.org/@types/react/-/react-19.2.18.tgz",
      "integrity": "sha512-AnzbBERsrLKtk2XSfTbYRLjQPdy116Sty4q+T+Bp3IC4l6jNBvreVPAHmpq9qhXQM7CXZPjLVmGMw9sy+hxQ3w==",
      "license": "MIT",
      "dependencies": {
        "csstype": "^3.2.2"
      }
    },
    "node_modules/csstype": {
      "version": "3.2.3",
      "resolved": "https://registry.npmjs.org/csstype/-/csstype-3.2.3.tgz",
      "integrity": "sha512-z1HGKcYy2xA8AGQfwrn0PAy+PB7X/GSj3UVJW9qKyn43xWa+gl5nXmU4qqLMRzWVLFC8KusUX8T/0kCiOYpAIQ==",
      "license": "MIT"
    }
  }
}

{
  "name": "sample-types-react-use-action-state",
  "version": "1.0.0",
  "private": true,
  "type": "module",
  "license": "MIT-0",
  "dependencies": {
    "@types/react": "19.2.18"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify useActionState in pkg:npm/%40types/react@19.2.18",
  "kind": "HOW",
  "packages": [
    "pkg:npm/%40types/react@19.2.18"
  ],
  "symbols": [
    "useActionState"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "packageManager": "npm@10.9.8",
    "runtime": "node@22.23.2"
  }
}

import assert from 'node:assert/strict';
import { createRequire } from 'node:module';
import fs from 'node:fs';
import path from 'node:path';

const require = createRequire(import.meta.url);

// 1. Resolve @types/react package manifest and verify declaration entry points and metadata
const pkgPath = require.resolve('@types/react/package.json');
const pkg = JSON.parse(fs.readFileSync(pkgPath, 'utf8'));

assert.equal(pkg.name, '@types/react', 'Package name must be @types/react');
assert.equal(pkg.version, '19.2.18', 'Package version must be 19.2.18');
assert.equal(pkg.types, 'index.d.ts', 'Package types entry must point to index.d.ts');
assert.equal(pkg.typeScriptVersion, '5.6', 'TypeScript version must be 5.6');
assert.ok(pkg.typesVersions && pkg.typesVersions['<=5.0'], 'Package must declare typesVersions for TypeScript <= 5.0');
assert.deepEqual(pkg.typesVersions['<=5.0']['*'], ['ts5.0/*'], 'typesVersions <=5.0 fallback path must point to ts5.0/*');

const typesDir = path.dirname(pkgPath);
const indexDts = fs.readFileSync(path.join(typesDir, 'index.d.ts'), 'utf8');

// 2. Verify unary useActionState hook signature (without payload)
assert.ok(
  indexDts.includes('export function useActionState<State>(') &&
  indexDts.includes('action: (state: Awaited<State>) => State | Promise<State>,') &&
  indexDts.includes('initialState: Awaited<State>,') &&
  indexDts.includes('permalink?: string,') &&
  indexDts.includes('): [state: Awaited<State>, dispatch: () => void, isPending: boolean];'),
  'index.d.ts must declare unary useActionState hook signature returning parameterless dispatch'
);

// 3. Verify parameterized useActionState hook signature (with payload)
assert.ok(
  indexDts.includes('export function useActionState<State, Payload>(') &&
  indexDts.includes('action: (state: Awaited<State>, payload: Payload) => State | Promise<State>,') &&
  indexDts.includes('initialState: Awaited<State>,') &&
  indexDts.includes('permalink?: string,') &&
  indexDts.includes('): [state: Awaited<State>, dispatch: (payload: Payload) => void, isPending: boolean];'),
  'index.d.ts must declare parameterized useActionState hook signature returning payload dispatch'
);

// 4. Verify Awaited<State> handling and return tuple type structure
assert.ok(
  indexDts.includes('[state: Awaited<State>, dispatch: () => void, isPending: boolean]') &&
  indexDts.includes('[state: Awaited<State>, dispatch: (payload: Payload) => void, isPending: boolean]'),
  'useActionState return tuple must contain named elements: state, dispatch, isPending'
);

// 5. Verify optional permalink parameter across overloads
const useActionStateMatches = indexDts.match(/export function useActionState[\s\S]*?\): \[state: Awaited<State>/g);
assert.ok(useActionStateMatches && useActionStateMatches.length >= 2, 'Must have at least 2 useActionState overloads');
for (const match of useActionStateMatches) {
  assert.ok(match.includes('permalink?: string'), 'All useActionState overloads must accept optional permalink');
}

// 6. Verify ts5.0 compatibility fallback declarations
const ts5IndexDts = fs.readFileSync(path.join(typesDir, 'ts5.0', 'index.d.ts'), 'utf8');
assert.ok(
  ts5IndexDts.includes('export function useActionState<State>(') &&
  ts5IndexDts.includes('action: (state: Awaited<State>) => State | Promise<State>,') &&
  ts5IndexDts.includes('initialState: Awaited<State>,') &&
  ts5IndexDts.includes('): [state: Awaited<State>, dispatch: () => void, isPending: boolean];'),
  'ts5.0/index.d.ts must declare unary useActionState hook signature'
);
assert.ok(
  ts5IndexDts.includes('export function useActionState<State, Payload>(') &&
  ts5IndexDts.includes('action: (state: Awaited<State>, payload: Payload) => State | Promise<State>,') &&
  ts5IndexDts.includes('initialState: Awaited<State>,') &&
  ts5IndexDts.includes('): [state: Awaited<State>, dispatch: (payload: Payload) => void, isPending: boolean];'),
  'ts5.0/index.d.ts must declare parameterized useActionState hook signature'
);

console.log('Contract tests passed successfully.');