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.

})
    ).toEqual({
      displayName: 'Bar',
      parentDisplayName: 'Foo',
      children: [],
    });
    ReactDOM.unmountComponentAtNode(node);
    expect(
      getTree(barInstance._debugID, {
        includeParentDisplayName: true,
        expectedParentID: fooInstance._debugID,
      })
    ).toEqual({
      displayName: 'Bar',
      parentDisplayName: 'Foo',
      children: [],
    });
    ReactComponentTreeDevtool.purgeUnmountedComponents();
    expect(
      getTree(barInstance._debugID, {includeParentDisplayName: true})
    ).toEqual({
      displayName: 'Unknown',
      children: [],
    });
  });
  it('reports update counts', () => {
    var node = document.createElement('div');
    ReactDOM.render(<div className="a" />, node);
    var divID = ReactComponentTreeDevtool.getRootIDs()[0];
    expect(ReactComponentTreeDevtool.getUpdateCount(divID)).toEqual(0);