Add focus and scroll management for new router

packages/next/client/components/app-router.client.tsx

@@ -3,10 +3,12 @@ import { createFromReadableStream } from 'next/dist/compiled/react-server-dom-we
 import {
   AppRouterContext,
   AppTreeContext,
-  CacheNode,
   FullAppTreeContext,
 } from '../../shared/lib/app-router-context'
-import type { AppRouterInstance } from '../../shared/lib/app-router-context'
+import type {
+  CacheNode,
+  AppRouterInstance,
+} from '../../shared/lib/app-router-context'
 import type { FlightRouterState, FlightData } from '../../server/app-render'
 import { reducer } from './reducer'
 import {
@@ -117,19 +119,19 @@ export default function AppRouter({
   children: React.ReactNode
   hotReloader?: React.ReactNode
 }) {
-  const [{ tree, cache, pushRef, canonicalUrl }, dispatch] = React.useReducer<
-    typeof reducer
-  >(reducer, {
-    tree: initialTree,
-    cache: {
-      data: null,
-      subTreeData: children,
-      parallelRoutes:
-        typeof window === 'undefined' ? new Map() : initialParallelRoutes,
-    },
-    pushRef: { pendingPush: false, mpaNavigation: false },
-    canonicalUrl: initialCanonicalUrl,
-  })
+  const [{ tree, cache, pushRef, focusRef, canonicalUrl }, dispatch] =
+    React.useReducer<typeof reducer>(reducer, {
+      tree: initialTree,
+      cache: {
+        data: null,
+        subTreeData: children,
+        parallelRoutes:
+          typeof window === 'undefined' ? new Map() : initialParallelRoutes,
+      },
+      pushRef: { pendingPush: false, mpaNavigation: false },
+      focusRef: { focus: false },
+      canonicalUrl: initialCanonicalUrl,
+    })
 
   useEffect(() => {
     initialParallelRoutes = null!
@@ -302,6 +304,7 @@ export default function AppRouter({
           value={{
             changeByServerResponse,
             tree,
+            focusRef,
           }}
         >
           <AppRouterContext.Provider value={appRouter}>

packages/next/client/components/layout-router.client.tsx

@@ -1,4 +1,4 @@
-import React, { useContext } from 'react'
+import React, { useContext, useEffect, useRef } from 'react'
 import type { ChildProp } from '../../server/app-render'
 import type { ChildSegmentMap } from '../../shared/lib/app-router-context'
 import type {
@@ -61,8 +61,20 @@ export function InnerLayoutRouter({
   isActive: boolean
   path: string
 }) {
-  const { changeByServerResponse, tree: fullTree } =
-    useContext(FullAppTreeContext)
+  const {
+    changeByServerResponse,
+    tree: fullTree,
+    focusRef,
+  } = useContext(FullAppTreeContext)
+  const focusAndScrollRef = useRef<HTMLDivElement>(null)
+
+  useEffect(() => {
+    if (focusRef.focus && focusAndScrollRef.current) {
+      focusRef.focus = false
+      focusAndScrollRef.current.focus()
+      focusAndScrollRef.current.scrollIntoView()
+    }
+  }, [focusRef])
 
   let childNode = childNodes.get(path)
 
@@ -197,16 +209,18 @@ export function InnerLayoutRouter({
   }
 
   return (
-    <AppTreeContext.Provider
-      value={{
-        tree: tree[1][parallelRouterKey],
-        childNodes: childNode.parallelRoutes,
-        // TODO-APP: overriding of url for parallel routes
-        url: url,
-      }}
-    >
-      {childNode.subTreeData}
-    </AppTreeContext.Provider>
+    <div ref={focusAndScrollRef}>
+      <AppTreeContext.Provider
+        value={{
+          tree: tree[1][parallelRouterKey],
+          childNodes: childNode.parallelRoutes,
+          // TODO-APP: overriding of url for parallel routes
+          url: url,
+        }}
+      >
+        {childNode.subTreeData}
+      </AppTreeContext.Provider>
+    </div>
   )
 }
 

packages/next/client/components/reducer.ts

@@ -298,10 +298,20 @@ const walkTreeWithFlightDataPath = (
   return tree
 }
 
+type PushRef = {
+  pendingPush: boolean
+  mpaNavigation: boolean
+}
+
+type FocusRef = {
+  focus: boolean
+}
+
 type AppRouterState = {
   tree: FlightRouterState
   cache: CacheNode
-  pushRef: { pendingPush: boolean; mpaNavigation: boolean }
+  pushRef: PushRef
+  focusRef: FocusRef
   canonicalUrl: string
 }
 
@@ -349,6 +359,7 @@ export function reducer(
     return {
       canonicalUrl: href,
       pushRef: state.pushRef,
+      focusRef: state.focusRef,
       cache: state.cache,
       tree: tree,
     }
@@ -377,6 +388,7 @@ export function reducer(
       return {
         canonicalUrl: href,
         pushRef: { pendingPush, mpaNavigation: false },
+        focusRef: { focus: true },
         cache: state.cache,
         tree: optimisticTree,
       }
@@ -393,6 +405,7 @@ export function reducer(
         return {
           canonicalUrl: href,
           pushRef: { pendingPush, mpaNavigation: false },
+          focusRef: { focus: true },
           cache: cache,
           tree: mutable.patchedTree,
         }
@@ -430,6 +443,7 @@ export function reducer(
           return {
             canonicalUrl: href,
             pushRef: { pendingPush, mpaNavigation: false },
+            focusRef: { focus: true },
             cache: cache,
             tree: optimisticTree,
           }
@@ -446,6 +460,7 @@ export function reducer(
         return {
           canonicalUrl: flightData,
           pushRef: { pendingPush: true, mpaNavigation: true },
+          focusRef: { focus: false },
           cache: state.cache,
           tree: state.tree,
         }
@@ -474,6 +489,7 @@ export function reducer(
       return {
         canonicalUrl: href,
         pushRef: { pendingPush, mpaNavigation: false },
+        focusRef: { focus: true },
         cache: cache,
         tree: newTree,
       }
@@ -490,6 +506,7 @@ export function reducer(
       return {
         canonicalUrl: state.canonicalUrl,
         pushRef: state.pushRef,
+        focusRef: state.focusRef,
         tree: state.tree,
         cache: state.cache,
       }
@@ -500,6 +517,7 @@ export function reducer(
       return {
         canonicalUrl: flightData,
         pushRef: { pendingPush: true, mpaNavigation: true },
+        focusRef: { focus: false },
         cache: state.cache,
         tree: state.tree,
       }
@@ -525,6 +543,7 @@ export function reducer(
     return {
       canonicalUrl: state.canonicalUrl,
       pushRef: state.pushRef,
+      focusRef: state.focusRef,
       tree: newTree,
       cache: cache,
     }
@@ -546,6 +565,7 @@ export function reducer(
       return {
         canonicalUrl: href,
         pushRef: { pendingPush, mpaNavigation: false },
+        focusRef: { focus: true },
         cache: cache,
         tree: mutable.patchedTree,
       }
@@ -566,6 +586,7 @@ export function reducer(
       return {
         canonicalUrl: flightData,
         pushRef: { pendingPush: true, mpaNavigation: true },
+        focusRef: { focus: false },
         cache: state.cache,
         tree: state.tree,
       }
@@ -597,6 +618,8 @@ export function reducer(
     return {
       canonicalUrl: href,
       pushRef: { pendingPush, mpaNavigation: false },
+      // TODO-APP: Revisit if this needs to be true in certain cases
+      focusRef: { focus: false },
       cache: cache,
       tree: newTree,
     }

packages/next/shared/lib/app-router-context.ts

@@ -1,4 +1,5 @@
 import React from 'react'
+import type { FocusRef } from '../../client/components/reducer'
 import type { FlightRouterState, FlightData } from '../../server/app-render'
 
 export type ChildSegmentMap = Map<string, CacheNode>
@@ -36,6 +37,7 @@ export const FullAppTreeContext = React.createContext<{
     previousTree: FlightRouterState,
     flightData: FlightData
   ) => void
+  focusRef: FocusRef
 }>(null as any)
 
 if (process.env.NODE_ENV !== 'production') {