Jest snapshot tests result in Type error

First off kudos for this rather fun-to-use component :)

OK so the issue I am bumping into happens when I set up a snapshot test with Jest and react-test-renderer.

The test file is essentially:
```
import renderer from 'react-test-renderer';
import Table from '../Table';

it('matches the Table snapshot', () => {
var component = renderer.create(

);

let tree = component.toJSON();
expect(tree).toMatchSnapshot();
});
```
(Note the `Table` component is just a wrapper that defines some basic BootstrapTable props.)

And when running tests, I am alerted to this (partial stack trace):
```
TypeError: Cannot read property 'setAttribute' of null

at TableHeaderColumn.componentDidMount (../node_modules/react-bootstrap-table/lib/TableHeaderColumn.js:138:30)
at ../node_modules/react-test-renderer/lib/ReactCompositeComponent.js:265:25
```

which points back to this line in `TableHeaderColumn / ComponentDidMount`:
```
value: function componentDidMount() {
this.refs['header-col'].setAttribute('data-field', this.props.dataField);
}
```
Anyone else encounter this?

Am I doing something wrong? Apologies if should I be asking somewhere else on this; have been bouncing around Jest and React repos as well as here.