We purge it [here](https://github.com/facebook/react/blob/b11540ccb2321aeb7259fcf0b3a38aeeea35231d/src/isomorphic/ReactDebugTool.js#L88-L89) but this code doesn’t run because of the [early exit](https://github.com/facebook/react/blob/b11540ccb2321aeb7259fcf0b3a38aeeea35231d/src/isomorphic/ReactDebugTool.js#L53-L57).

Need to fix this and add a test case to make sure we don’t regress on it.

var measurements = measure(fn);
    var summary = ReactPerf.getWasted(measurements);
    expect(summary).toEqual([]);
  }
  it('should not count initial render as waste', function() {
    expectNoWaste(() => {
      ReactTestUtils.renderIntoDocument(<App />);
    });
  });
  it('should not count unmount as waste', function() {
    var container = document.createElement('div');
    ReactDOM.render(<Div>hello</Div>, container);
    expectNoWaste(() => {
      ReactDOM.unmountComponentAtNode(container);
    });
  });
  it('should not count content update as waste', function() {
    var container = document.createElement('div');
    ReactDOM.render(<Div>hello</Div>, container);
    expectNoWaste(() => {
      ReactDOM.render(<Div>hello world</Div>, container);
    });
  });
  it('should not count child addition as waste', function() {
    var container = document.createElement('div');
    ReactDOM.render(<Div><span /></Div>, container);
    expectNoWaste(() => {
      ReactDOM.render(<Div><span /><span /></Div>, container);