refactor: Add state to onExit method

packages/go_router/example/lib/on_exit.dart

@@ -22,7 +22,10 @@ final GoRouter _router = GoRouter(
           builder: (BuildContext context, GoRouterState state) {
             return const DetailsScreen();
           },
-          onExit: (BuildContext context) async {
+          onExit: (
+            BuildContext context,
+            GoRouterState state,
+          ) async {
             final bool? confirmed = await showDialog<bool>(
               context: context,
               builder: (_) {

packages/go_router/lib/src/delegate.dart

@@ -66,13 +66,17 @@ class GoRouterDelegate extends RouterDelegate<RouteMatchList>
       }
       walker = walker.matches.last;
     }
+    assert(walker is RouteMatch);
     if (state != null) {
       return state.maybePop();
     }
     // This should be the only place where the last GoRoute exit the screen.
     final GoRoute lastRoute = currentConfiguration.last.route;
     if (lastRoute.onExit != null && navigatorKey.currentContext != null) {
-      return !(await lastRoute.onExit!(navigatorKey.currentContext!));
+      return !(await lastRoute.onExit!(
+        navigatorKey.currentContext!,
+        walker.buildState(_configuration, currentConfiguration),
+      ));
     }
     return false;
   }
@@ -137,8 +141,10 @@ class GoRouterDelegate extends RouterDelegate<RouteMatchList>
     // a microtask in case the onExit callback want to launch dialog or other
     // navigator operations.
     scheduleMicrotask(() async {
-      final bool onExitResult =
-          await routeBase.onExit!(navigatorKey.currentContext!);
+      final bool onExitResult = await routeBase.onExit!(
+        navigatorKey.currentContext!,
+        match.buildState(_configuration, currentConfiguration),
+      );
       if (onExitResult) {
         _completeRouteMatch(result, match);
       }
@@ -217,14 +223,14 @@ class GoRouterDelegate extends RouterDelegate<RouteMatchList>
       }
 
       if (indexOfFirstDiff < currentGoRouteMatches.length) {
-        final List<GoRoute> exitingGoRoutes = currentGoRouteMatches
-            .sublist(indexOfFirstDiff)
-            .map<RouteBase>((RouteMatch match) => match.route)
-            .whereType<GoRoute>()
-            .toList();
-        return _callOnExitStartsAt(exitingGoRoutes.length - 1,
-                context: navigatorContext, routes: exitingGoRoutes)
-            .then<void>((bool exit) {
+        final List<RouteMatch> exitingMatches =
+            currentGoRouteMatches.sublist(indexOfFirstDiff).toList();
+        return _callOnExitStartsAt(
+          exitingMatches.length - 1,
+          context: navigatorContext,
+          matches: exitingMatches,
+          configuration: configuration,
+        ).then<void>((bool exit) {
           if (!exit) {
             return SynchronousFuture<void>(null);
           }
@@ -240,24 +246,42 @@ class GoRouterDelegate extends RouterDelegate<RouteMatchList>
   ///
   /// The returned future resolves to true if all routes below the index all
   /// return true. Otherwise, the returned future resolves to false.
-  static Future<bool> _callOnExitStartsAt(int index,
-      {required BuildContext context, required List<GoRoute> routes}) {
+  Future<bool> _callOnExitStartsAt(
+    int index, {
+    required BuildContext context,
+    required List<RouteMatch> matches,
+    required RouteMatchList configuration,
+  }) {
     if (index < 0) {
       return SynchronousFuture<bool>(true);
     }
-    final GoRoute goRoute = routes[index];
+    final RouteMatch match = matches[index];
+    final GoRoute goRoute = match.route;
     if (goRoute.onExit == null) {
-      return _callOnExitStartsAt(index - 1, context: context, routes: routes);
+      return _callOnExitStartsAt(
+        index - 1,
+        context: context,
+        matches: matches,
+        configuration: configuration,
+      );
     }
 
     Future<bool> handleOnExitResult(bool exit) {
       if (exit) {
-        return _callOnExitStartsAt(index - 1, context: context, routes: routes);
+        return _callOnExitStartsAt(
+          index - 1,
+          context: context,
+          matches: matches,
+          configuration: configuration,
+        );
       }
       return SynchronousFuture<bool>(false);
     }
 
-    final FutureOr<bool> exitFuture = goRoute.onExit!(context);
+    final FutureOr<bool> exitFuture = goRoute.onExit!(
+      context,
+      match.buildState(_configuration, configuration),
+    );
     if (exitFuture is bool) {
       return handleOnExitResult(exitFuture);
     }

packages/go_router/lib/src/route.dart

@@ -63,7 +63,8 @@ typedef NavigatorBuilder = Widget Function(
 ///
 /// If the return value is true or the future resolve to true, the route will
 /// exit as usual. Otherwise, the operation will abort.
-typedef ExitCallback = FutureOr<bool> Function(BuildContext context);
+typedef ExitCallback = FutureOr<bool> Function(
+    BuildContext context, GoRouterState state);
 
 /// The base class for [GoRoute] and [ShellRoute].
 ///

packages/go_router/lib/src/route_data.dart

@@ -63,6 +63,11 @@ abstract class GoRouteData extends RouteData {
   /// Corresponds to [GoRoute.redirect].
   FutureOr<String?> redirect(BuildContext context, GoRouterState state) => null;
 
+  /// Called when this route is removed from GoRouter's route history.
+  ///
+  /// Corresponds to [GoRoute.onExit].
+  FutureOr<bool> onExit(BuildContext context, GoRouterState state) => true;
+
   /// A helper function used by generated code.
   ///
   /// Should not be used directly.
@@ -106,6 +111,9 @@ abstract class GoRouteData extends RouteData {
     FutureOr<String?> redirect(BuildContext context, GoRouterState state) =>
         factoryImpl(state).redirect(context, state);
 
+    FutureOr<bool> onExit(BuildContext context, GoRouterState state) =>
+        factoryImpl(state).onExit(context, state);
+
     return GoRoute(
       path: path,
       name: name,
@@ -114,6 +122,7 @@ abstract class GoRouteData extends RouteData {
       redirect: redirect,
       routes: routes,
       parentNavigatorKey: parentNavigatorKey,
+      onExit: onExit,
     );
   }