import evalScript from '../lib/eval-script' const { __NEXT_DATA__: { errorComponent } } = window const ErrorComponent = evalScript(errorComponent).default require('react-hot-loader/patch') const next = window.next = require('./') const emitter = next.default(onError) function onError (err) { // just show the debug screen but don't render ErrorComponent // so that the current component doesn't lose props next.render({ err, emitter }) } let lastScroll emitter.on('before-reactdom-render', ({ Component }) => { // Remember scroll when ErrorComponent is being rendered to later restore it if (!lastScroll && Component === ErrorComponent) { const { pageXOffset, pageYOffset } = window lastScroll = { x: pageXOffset, y: pageYOffset } } }) emitter.on('after-reactdom-render', ({ Component }) => { if (lastScroll && Component !== ErrorComponent) { // Restore scroll after ErrorComponent was replaced with a page component by HMR const { x, y } = lastScroll window.scroll(x, y) lastScroll = null } })