Appears to be working in Firefox but at least Chrome & Safari are broken. Should be a really recent regression so very few possible changes to blame...

Easiest repo: the todo list on our homepage.

};
      this.addMatchers({
        toHaveInnerhtml: function(html) {
          var expected = '^' + quoteRegexp(html) + '$';
          return this.actual.match(new RegExp(expected));
        },
      });
    });
    it('should handle dangerouslySetInnerHTML', function() {
      var innerHTML = {__html: 'testContent'};
      expect(
        genMarkup({dangerouslySetInnerHTML: innerHTML})
      ).toHaveInnerhtml('testContent');
    });
  });
  describe('mountComponent', function() {
    var mountComponent;
    beforeEach(function() {
      mountComponent = function(props) {
        var container = document.createElement('div');
        ReactDOM.render(<div {...props} />, container);
      };
    });
    it('should not duplicate uppercased selfclosing tags', function() {
      var Container = React.createClass({
        render: function() {
          return React.createElement('BR', null);
        },
      });
      var returnedValue = ReactDOMServer.renderToString(<Container/>);