*feature*

>Warning: A component is `contentEditable` and contains `children` managed by React. It is now your responsibility to guarantee that none of those nodes are unexpectedly modified or duplicated. This is probably not intentional.

It would help heaps if I would know _which_ component is causing this.
};
      var container = document.createElement('div');
      ReactDOM.render(<img src={obj} />, container);
      expect(container.firstChild.src).toBe('hello');
      ReactDOM.render(<svg arabicForm={obj} />, container);
      expect(container.firstChild.getAttribute('arabic-form')).toBe('hello');
      ReactDOM.render(<div unknown={obj} />, container);
      expect(container.firstChild.getAttribute('unknown')).toBe('hello');
    });
    it('passes objects on known SVG attributes if they do not define toString', () => {
      var obj = {};
      var container = document.createElement('div');
      ReactDOM.render(<svg arabicForm={obj} />, container);
      expect(container.firstChild.getAttribute('arabic-form')).toBe(
        '[object Object]',
      );
    });
    it('passes objects on custom attributes if they do not define toString', () => {
      var obj = {};
      var container = document.createElement('div');
      ReactDOM.render(<div unknown={obj} />, container);
      expect(container.firstChild.getAttribute('unknown')).toBe(
        '[object Object]',
      );
    });
    it('allows objects that inherit a custom toString method', function() {
      var parent = {toString: () => 'hello.jpg'};
      var child = Object.create(parent);
      var el = ReactTestUtils.renderIntoDocument(<img src={child} />);
      expect(el.src).toBe('hello.jpg');