Redux-form 6.0.1 unit test issue - unit-testing

Question

I just upgraded Redux-Form from 5.3.2 to 6.0.1, but the unit test that works in 5.3.2 failed in 6.0.1.
/* MyForm.jsx */
...
import { Field, reduxForm } from 'redux-form';
class MyForm extends Component {
...
<form onSubmit={handleSubmit(...)}>
...
}
export default reduxForm({
form: 'myForm'
})(MyForm);
I mounted the form reducer before render the form:
import {reducer as formReducer} from 'redux-form';
const myReducer = combineReducers({
...
form: formReducer
});
Here is the store, created in top level component:
const createStoreWithMiddleware = applyMiddleware(thunkMiddleware)(createStore);
const store = createStoreWithMiddleware(myReducer);
My test case (Karma + jasmine), which works in 5.3.2, but failed in 6.0.1
/* form.test.js */
import React, { PropTypes } from 'react';
import TestUtils from 'react/lib/ReactTestUtils';
import findDOMNode from 'react/lib/findDOMNode';
import { Provider } from 'react-redux';
...
import MyForm from '../MyForm';
const createStoreWithMiddleware = applyMiddleware(thunkMiddleware)(createStore);
const store = createStoreWithMiddleware(myReducer);
describe('MyForm', () => {
beforeAll(function() {
this.props = {
...
store: store
}
});
it('should render', function() {
const element = TestUtils.renderIntoDocument(
<MyForm {...this.props} />
);
expect(element).toBeTruthy();
});
error: Invariant Violation: Could not find "store" in either the context or props of "Connect(ConnectedField)". Either wrap the root component in a <Provider>, or explicitly pass "store" as a prop to "Connect(ConnectedField)".
If I use Provider to pass in store, will get another error:
it('should render', function() {
const element = TestUtils.renderIntoDocument(
<Provider store={ store }>
{ () => <MyForm {...this.props} />}
</Provider>
);
expect(element).toBeTruthy();
});
*
error: Invariant Violation: onlyChild must be passed a children with exactly one child.
ERROR: 'Warning: Failed propType: Invalid prop `children` supplied to `Provider`, expected a single ReactElement.'
*
Any ideas why the test failed? I searched online but could not find information that specific for this topic.
Thanks,