How to use the next/router.router function in next

return foo;
  },
  events: {
    on: (eventName: EventName, handler?: EventHandler | ErrorEventHandler) => {
      // let foo: void;
      // return foo;
    },
    off: (eventName: EventName, handler?: EventHandler | ErrorEventHandler) => {
      // let foo: void;
      // return foo;
    }
  }
};

// @ts-ignore
Router.router = mockRouter as RouterProps;

// https://github.com/zeit/next.js/issues/5205#issuecomment-422846339
export default class MockNextContext extends React.Component {
  static childContextTypes = {
    headManager: PropTypes.object,
    router: PropTypes.object
  };

  getChildContext() {
    const { headManager, router } = this.props;
    return {
      headManager: {
        updateHead() {},
        ...headManager
      },
      router: Object.assign(mockRouter, router)

componentWillUnmount() {
      Router.router.events.off("routeChangeComplete", this.trackPageview);
    }

componentWillUnmount() {
      Router.router.events.off("routeChangeComplete", this.trackPageview);
    }

componentDidMount() {
      initGa();
      this.trackSourceView();
      Router.router.events.on("routeChangeComplete", this.trackSourceView);
    }

withState('texts', 'onTextChange', () => {
         if (!Router.router) return ''
         const { query } = Router.router
         if (!query.searchTexts) {
           return ''
         }
         return query.searchTexts
       }),
       graphql(gql`

router: { ...mockedRouter, ...mockRouter }
      }
    }
    render () {
      return this.props.children
    }
  }

  MockRouterContext.childContextTypes = {
    router: PropTypes.object
  }

  return MockRouterContext
}

Router.router = mockedRouter

const StorybookRouterFix = withMockRouterContext(mockedRouter)

function MockProjectContext({ children, theme }) {
  return (
    
      
        
          
            {children}
          
        
      
    
  )
}

componentDidMount() {
    this.sbs = ScrollBar.initAll()
    if (window.scrollHandlers) {
      window.scrollHandlers.forEach(handler => {
        this.sbs[0].addListener(handler)
      })
    }
    this.route = Router.router ? Router.router.pathname : ''
    this.forceUpdate()
  }