Enzyme mount() vs shallow() for component context providers

test.js

import React, { Component, PropTypes } from 'react';
import { shallow, mount } from 'enzyme';

class ContextProvider extends Component {
  getChildContext() {
    return {
      foo: 'bar'
    };
  }

  render() {
    return this.props.children;
  }
}

ContextProvider.childContextTypes = {
  foo: PropTypes.string
};

class ContextReceiver extends Component {
  render() {
    return (
      <div>
        {this.context.foo}
      </div>
    );
  }
}

ContextReceiver.contextTypes = {
  foo: PropTypes.string
};

describe('context passing', () => {
  it('mount', () => {
    const wrapper = mount(
      <ContextProvider>
        <ContextReceiver />
      </ContextProvider>
    );
    // Passes!
    expect(wrapper.text()).toEqual('bar');
  });

  it('shallow', () => {
    const wrapper = shallow(
      <ContextProvider>
        <ContextReceiver />
      </ContextProvider>
    );
    // Fails: Expected "bar" Receiver "<ContextReceiver />"
    // Which makes a lot of sense, because Shallow Rendering is meant to render
    // only the top level component, which in this case is ContextProvider
    expect(wrapper.text()).toEqual('bar');
  });
});