Update Props

// This is an example of how to update the props of a rendered component.
// the basic idea is to simply call `render` again and provide the same container
// that your first call created for you.
import React, {useRef} from 'react'
import {render, screen} from '@testing-library/react'
let idCounter = 1
const NumberDisplay = ({number}) => {
const id = useRef(idCounter++) // to ensure we don't remount a different instance
return (
<div>
<span data-testid="number-display">{number}</span>
<span data-testid="instance-id">{id.current}</span>
</div>
)
}
test('calling render with the same component on the same container does not remount', () => {
const {rerender} = render(<NumberDisplay number={1} />)
expect(screen.getByTestId('number-display')).toHaveTextContent('1')
// re-render the same component with different props
rerender(<NumberDisplay number={2} />)
expect(screen.getByTestId('number-display')).toHaveTextContent('2')
expect(screen.getByTestId('instance-id')).toHaveTextContent('1')
})
Last updated on by Nick McCurdy