basico-libreriasui/src/MediaImg/MediaImg.spec.js

Esta es una libreria en la que tu podras importar componentes de mi practica de platzi

import { render } from '@testing-library/react';
import MediaImg from './MediaImg';
import '@testing-library/jest-dom/extend-expect';

describe('@components/MediaImg', () => {
  it('kinewofinweoifnoine', () => {
    //arrange
    const { getByRole } = render(
      <MediaImg
        alt="PlatziCoolImg"
        src="http://www.platziversosupercool.com/img"
      />
    );
    //act
    const MediaImgTest = getByRole('img');
    //assert
    expect(MediaImgTest).toBeInTheDocument();
    expect(MediaImgTest).toHaveAttribute(
      'src',
      'http://www.platziversosupercool.com/img'
    );
    expect(MediaImgTest).toHaveAttribute('alt', 'PlatziCoolImg');
  });
  it('Probar que el width y height sean 200px y border-radius 8px', () => {
    //arrange
    const { getByRole } = render(
      <MediaImg
        alt="PlatziCoolImg"
        src="http://www.platziversosupercool.com/img"
        width="200px"
        height="200px"
        borderRadius="8px"
      />
    );
    //act
    const MediaImgTest = getByRole('img');
    //assert
    expect(MediaImgTest).toHaveStyle(
      'width:200px;height:200px;border-radius:8px;'
    );
  });
});