import React, { useState, useContext, useCallback } from 'react';
const CounterStepContext = React.createContext(1);
export const CounterStepProvider = ({ step, children }: any) => (
 <CounterStepContext.Provider value={step}>
 {children}
 </CounterStepContext.Provider>
);
export function useCounter(initialValue = 0) {
 const [count, setCount] = useState(initialValue);
 const step = useContext(CounterStepContext);
 const increment = useCallback(() => setCount((x) => x + step), [step]);
 const reset = useCallback(() => setCount(initialValue), [initialValue]);
 return { count, increment, reset };
}

import { renderHook, act } from '@testing-library/react-hooks';
import { useCounter, CounterStepProvider } from './useCounter';
test('should use custom step when incrementing', () => {
 const { result } = renderHook(() => useCounter(), {
 wrapper: ({ children }) => (
 <CounterStepProvider step={2}>{children}</CounterStepProvider>
 ),
 });
 act(() => {
 result.current.increment();
 });
 expect(result.current.count).toBe(2);
});

FAIL src/test/useCounter.test.tsx
 ✕ should use custom step when incrementing (5 ms)
 ●くろまる should use custom step when incrementing
 Objects are not valid as a React child (found: object with keys {type, props, key, ref, __k, __, __b, __e, __d, __c, __h, constructor, __v, __source, __self}). If you meant to render a collection of children, use an array instead.
 3 |
 4 | test('should use custom step when incrementing', () => {
 > 5 | const { result } = renderHook(() => useCounter(), {
 | ^
 6 | wrapper: ({ children }) => (
 7 | <CounterStepProvider step={2}>{children}</CounterStepProvider>
 8 | ),
 at throwOnInvalidObjectType (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:4537:15)
 at reconcileChildFibers (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:5439:7)
 at reconcileChildren (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:7984:28)
 at mountIndeterminateComponent (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:8810:5)
 at beginWork (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:9966:16)
 at performUnitOfWork (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:13800:12)
 at workLoopSync (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:13728:5)
 at renderRootSync (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:13691:7)
 at performSyncWorkOnRoot (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:13404:18)
 at node_modules/react-test-renderer/cjs/react-test-renderer.development.js:2537:26
 at unstable_runWithPriority (node_modules/scheduler/cjs/scheduler.development.js:468:12)
 at runWithPriority (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:2486:10)
 at flushSyncCallbackQueueImpl (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:2532:9)
 at flushSyncCallbackQueue (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:2519:3)
 at batchedUpdates (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:13459:7)
 at act (node_modules/react-test-renderer/cjs/react-test-renderer.development.js:15280:14)
 at render (node_modules/@testing-library/react-hooks/lib/native/pure.js:73:34)
 at renderHook (node_modules/@testing-library/react-hooks/lib/core/index.js:114:5)
 at Object.<anonymous> (src/test/useCounter.test.tsx:5:22)
Test Suites: 1 failed, 1 total
Tests: 1 failed, 1 total
Snapshots: 0 total
Time: 0.337 s, estimated 1 s
Ran all test suites.