Problema ao ler prepareStyles, workaround

Test.jsx

import React from 'react'
import { TextField } from 'material-ui'

const Test = () => (
  <div>
    <TextField />
    <TextField />
  </div>
);

export default Test;

Test.test.jsx

import React from 'react';
import { shallow } from 'enzyme';
import getMuiTheme from 'material-ui/styles/getMuiTheme';
import Test from './Test';

describe('Account test', () => {
  it('Number of inputs presence must be equals 2', () => {
    const component = shallow(
      <Test />,
      {
        context: {
        muiTheme: getMuiTheme(),
      },
        childContextTypes: {
          muiTheme: PropTypes.object.isRequired,
        }
      }
    );
  
    expect(component.find('TextField').length).toBe(2)
  });
});