React Testing Library And Jest- The Complete Guide -

await user.type(screen.getByLabelText(/email/i), 'user@example.com') await user.type(screen.getByLabelText(/password/i), 'secret123') await user.click(screen.getByRole('button', name: /submit/i ))

export default testEnvironment: 'jsdom', setupFilesAfterEnv: ['<rootDir>/src/setupTests.js'], transform: jsx,

// Test behavior, not implementation expect(screen.getByText('Welcome John')).toBeInTheDocument() React Testing Library and Jest- The Complete Guide

render(<Button onClick=handleClick>Click Me</Button>)

expect(screen.getByText('Done')).toBeInTheDocument() ) await user

jest.useRealTimers() // restore Controlled component const Toggle = () => const [on, setOn] = useState(false) return ( <button onClick=() => setOn(!on)> on ? 'ON' : 'OFF' </button> )

expect(screen.getByText('Loading...')).toBeInTheDocument() 'secret123') await user.click(screen.getByRole('button'

test('consumes context', () => const getByText = customRender(<ThemedComponent />, providerProps: initialTheme: 'dark' ) expect(getByText(/dark mode/i)).toBeInTheDocument() ) import renderHook, act from '@testing-library/react' const useCounter = (initial = 0) => const [count, setCount] = useState(initial) const increment = () => setCount(c => c + 1) return count, increment