Testen von Custom-Hook-Zustandsübergängen mit renderHook

import { renderHook, act } from '@testing-library/react';
import { useState, useCallback } from 'react';
 
function useCounter(initialValue = 0) {
  const [count, setCount] = useState(initialValue);
  const increment = useCallback(() => setCount((prev) => prev + 1), []);
  return { count, increment };
}
 
describe('useCounter', () => {
  it('increments count correctly on action', () => {
    const { result } = renderHook(() => useCounter(5));
    expect(result.current.count).toBe(5);
 
    act(() => {
      result.current.increment();
    });
 
    expect(result.current.count).toBe(6);
  });
});