Add router state to handle pre-redirect (#283)

Author: ije

framework/core/redirect.ts

@@ -1,6 +1,18 @@
 import util from '../../shared/util.ts'
 import events from './events.ts'
 
+const routerState = {
+  ready: false,
+  hasDeferredRedirect: false,
+}
+
+events.once('routerstate', state => {
+  if (routerState.hasDeferredRedirect) {
+    events.emit('popstate', { type: 'popstate', resetScroll: true })
+  }
+  Object.assign(routerState, state)
+})
+
 export async function redirect(url: string, replace?: boolean) {
   const { location, history } = window as any
 
@@ -19,5 +31,10 @@ export async function redirect(url: string, replace?: boolean) {
   } else {
     history.pushState(null, '', url)
   }
-  events.emit('popstate', { type: 'popstate', resetScroll: true })
+
+  if (routerState.ready) {
+    events.emit('popstate', { type: 'popstate', resetScroll: true })
+  } else if (!routerState.hasDeferredRedirect) {
+    routerState.hasDeferredRedirect = true
+  }
 }

framework/react/components/Router.ts

@@ -72,6 +72,7 @@ export default function Router({
   useEffect(() => {
     window.addEventListener('popstate', onpopstate)
     events.on('popstate', onpopstate)
+    events.emit('routerstate', { ready: true })
 
     return () => {
       window.removeEventListener('popstate', onpopstate)