text: import React from 'react';
  import renderer from 'react-test-renderer';
  import Jest from './Jest';
  
  test('Link changes the class when hovered', () => {
    const component = renderer.create(
      <Jest page="http://www.facebook.com">Facebook</Jest>,
    );
    let tree = component.toJSON();
    expect(tree).toMatchSnapshot();
  
    // manually trigger the callback
    tree.props.onMouseEnter();
    // re-rendering
    tree = component.toJSON();
    expect(tree).toMatchSnapshot();
  
    // manually trigger the callback
    tree.props.onMouseLeave();
    // re-rendering
    tree = component.toJSON();
    expect(tree).toMatchSnapshot();
  });