feat: add missing React 19 hooks to renderer dispatcher

src/renderer/__tests__/hooks.node.test.tsx

@@ -1,4 +1,19 @@
-import React, { useCallback, useEffect, useId, useLayoutEffect, useMemo, useReducer, useRef, useState } from 'react'
+import React, {
+  createContext,
+  Usable,
+  use,
+  useActionState,
+  useCallback,
+  useEffect,
+  useEffectEvent,
+  useId,
+  useLayoutEffect,
+  useMemo,
+  useOptimistic,
+  useReducer,
+  useRef,
+  useState,
+} from 'react'
 
 import { Text } from '../../jsx/Text'
 import { renderVoltraVariantToJson } from '../renderer'
@@ -200,4 +215,85 @@ describe('Hooks', () => {
     const output = renderVoltraVariantToJson(<Component />)
     expect(output.c).toBe('2')
   })
+
+  test('16. use(context) reads context value', () => {
+    const ThemeContext = createContext('light')
+    const Consumer = () => {
+      const theme = use(ThemeContext)
+      return <Text>{theme}</Text>
+    }
+    const output = renderVoltraVariantToJson(
+      <ThemeContext.Provider value="dark">
+        <Consumer />
+      </ThemeContext.Provider>
+    )
+    expect(output.c).toBe('dark')
+  })
+
+  test('17. use(context) without provider returns default', () => {
+    const ThemeContext = createContext('light')
+    const Consumer = () => {
+      const theme = use(ThemeContext)
+      return <Text>{theme}</Text>
+    }
+    const output = renderVoltraVariantToJson(<Consumer />)
+    expect(output.c).toBe('light')
+  })
+
+  test('18. use(promise) throws', () => {
+    const Component = () => {
+      use(Promise.resolve('value'))
+      return <Text>test</Text>
+    }
+    expect(() => renderVoltraVariantToJson(<Component />)).toThrow('use() with promises is not supported in Voltra')
+  })
+
+  test('19. use(unsupportedValue) throws', () => {
+    const Component = () => {
+      use('not a context or promise' as unknown as Usable<unknown>)
+      return <Text>test</Text>
+    }
+    expect(() => renderVoltraVariantToJson(<Component />)).toThrow('An unsupported type was passed to use()')
+  })
+
+  test('20. useActionState returns [initialState, dispatch, false]', () => {
+    const action = jest.fn()
+    let state, dispatch, isPending
+    const Component = () => {
+      ;[state, dispatch, isPending] = useActionState(action, { count: 0 })
+      return <Text>{state.count}</Text>
+    }
+    const output = renderVoltraVariantToJson(<Component />)
+    expect(output.c).toBe('0')
+    expect(state).toEqual({ count: 0 })
+    expect(typeof dispatch).toBe('function')
+    expect(isPending).toBe(false)
+    dispatch()
+    expect(action).not.toHaveBeenCalled()
+  })
+
+  test('21. useOptimistic returns [passthrough, setter]', () => {
+    let value, setOptimistic
+    const Component = () => {
+      ;[value, setOptimistic] = useOptimistic('real')
+      return <Text>{value}</Text>
+    }
+    const output = renderVoltraVariantToJson(<Component />)
+    expect(output.c).toBe('real')
+    expect(value).toBe('real')
+    expect(typeof setOptimistic).toBe('function')
+    setOptimistic('optimistic')
+    expect(value).toBe('real')
+  })
+
+  test('22. useEffectEvent returns callback identity', () => {
+    const fn = jest.fn()
+    let eventFn
+    const Component = () => {
+      eventFn = useEffectEvent(fn)
+      return <Text>test</Text>
+    }
+    renderVoltraVariantToJson(<Component />)
+    expect(eventFn).toBe(fn)
+  })
 })

src/renderer/dispatcher.ts

@@ -2,23 +2,34 @@ import React, { Context, ReactDispatcher, ReactHooksDispatcher } from 'react'
 
 import { ContextRegistry } from './context-registry.js'
 
+const REACT_CONTEXT_TYPE = Symbol.for('react.context')
+const REACT_MEMO_CACHE_SENTINEL = Symbol.for('react.memo_cache_sentinel')
+
 declare module 'react' {
+  type HookFn = (...args: any[]) => any
+
   export type ReactHooksDispatcher = {
-    useState: typeof import('react').useState
-    useReducer: typeof import('react').useReducer
-    useEffect: typeof import('react').useEffect
-    useLayoutEffect: typeof import('react').useLayoutEffect
-    useInsertionEffect: typeof import('react').useInsertionEffect
-    useCallback: typeof import('react').useCallback
-    useMemo: typeof import('react').useMemo
-    useRef: typeof import('react').useRef
-    useContext: typeof import('react').useContext
-    useId: typeof import('react').useId
-    useImperativeHandle: typeof import('react').useImperativeHandle
-    useDebugValue: typeof import('react').useDebugValue
-    useDeferredValue: typeof import('react').useDeferredValue
-    useTransition: typeof import('react').useTransition
-    useSyncExternalStore: typeof import('react').useSyncExternalStore
+    useState: HookFn
+    useReducer: HookFn
+    useEffect: HookFn
+    useLayoutEffect: HookFn
+    useInsertionEffect: HookFn
+    useCallback: HookFn
+    useMemo: HookFn
+    useRef: HookFn
+    useContext: HookFn
+    useId: HookFn
+    useImperativeHandle: HookFn
+    useDebugValue: HookFn
+    useDeferredValue: HookFn
+    useTransition: HookFn
+    useSyncExternalStore: HookFn
+    use: HookFn
+    useActionState: HookFn
+    useOptimistic: HookFn
+    useEffectEvent: HookFn
+    useMemoCache: HookFn
+    useCacheRefresh: HookFn
   }
 
   export type ReactDispatcher = {
@@ -30,6 +41,27 @@ declare module 'react' {
 
 export const getHooksDispatcher = (registry: ContextRegistry): ReactHooksDispatcher => ({
   useContext: <T>(context: Context<T>) => registry.readContext(context),
+  use: <T>(usable: React.Usable<T>): T => {
+    if (
+      usable !== null &&
+      typeof usable === 'object' &&
+      (usable as { $$typeof?: symbol }).$$typeof === REACT_CONTEXT_TYPE
+    ) {
+      return registry.readContext(usable as unknown as Context<T>)
+    }
+
+    if (
+      usable !== null &&
+      (typeof usable === 'object' || typeof usable === 'function') &&
+      typeof (usable as { then?: unknown }).then === 'function'
+    ) {
+      throw new Error(
+        'use() with promises is not supported in Voltra. Async data fetching is not available in this synchronous renderer.'
+      )
+    }
+
+    throw new Error(`An unsupported type was passed to use(): ${String(usable)}`)
+  },
   useState: <S>(initial?: S | (() => S)) => [
     typeof initial === 'function' ? (initial as () => S)() : initial,
     () => {}, // No-op setter
@@ -58,6 +90,19 @@ export const getHooksDispatcher = (registry: ContextRegistry): ReactHooksDispatc
   useSyncExternalStore: (_, getSnapshot) => {
     return getSnapshot()
   },
+  // No-op stubs for React 19 hooks
+  useActionState: <S>(_: unknown, initialState: S, _permalink?: string) =>
+    [initialState, () => {}, false] as [S, () => void, boolean],
+  useOptimistic: <T>(passthrough: T) => [passthrough, () => {}] as [T, (action: unknown) => void],
+  useEffectEvent: <T extends Function>(callback: T): T => callback,
+  useMemoCache: (size: number) => {
+    const data = new Array<unknown>(size)
+    for (let i = 0; i < size; i++) {
+      data[i] = REACT_MEMO_CACHE_SENTINEL
+    }
+    return data
+  },
+  useCacheRefresh: () => () => {},
 })
 
 export const getReactCurrentDispatcher = (): ReactDispatcher => {