next.js/test/integration/app-aspath/pages/_app.js

import React from 'react'
import App, {Container} from 'next/app'

export default class MyApp extends App {
  // find this

  static async getInitialProps ({ ctx }) {
    const { query, pathname, asPath } = ctx
    return {url: {query, pathname, asPath}}
  }

  render () {
    const {Component, url} = this.props
    return <Container><Component url={url} /></Container>
  }
}