Pesto home stack (#5168)

examples/flutter_gallery/lib/demo/pesto_demo.dart

@@ -142,20 +142,25 @@ class _PestoDemoState extends State<PestoDemo> {
           new DrawerItem(
             child: new Text('Home'),
             selected: !config.showFavorites,
-            onPressed: () => Navigator.pushNamed(context, PestoDemo.routeName)
+            onPressed: () {
+              Navigator.popUntil(context, ModalRoute.withName('/pesto'));
+            }
           ),
           new DrawerItem(
             child: new Text('Favorites'),
             selected: config.showFavorites,
-            onPressed: () { _showFavorites(context); }
+            onPressed: () {
+              if (config.showFavorites)
+                Navigator.pop(context);
+              else
+                _showFavorites(context);
+            }
           ),
           new Divider(),
           new DrawerItem(
             child: new Text('Return to Gallery'),
             onPressed: () {
-              Navigator.of(context)
+              Navigator.popUntil(context, ModalRoute.withName('/'));
-                ..pop()  // Close the drawer.
-                ..pop();  // Go back to the gallery.
             }
           ),
         ]
@@ -193,6 +198,7 @@ class _PestoDemoState extends State<PestoDemo> {
 
   void _showFavorites(BuildContext context) {
     Navigator.push(context, new MaterialPageRoute<Null>(
+      settings: const RouteSettings(name: "/pesto/favorites"),
       builder: (BuildContext context) {
         return new PestoDemo(showFavorites: true);
       }
@@ -201,6 +207,7 @@ class _PestoDemoState extends State<PestoDemo> {
 
   void _showRecipe(BuildContext context, Recipe recipe) {
     Navigator.push(context, new MaterialPageRoute<Null>(
+      settings: const RouteSettings(name: "/pesto/recipe"),
       builder: (BuildContext context) {
         return new Theme(
           data: _kTheme,

examples/flutter_gallery/test/pesto_test.dart

@@ -0,0 +1,55 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:flutter_gallery/main.dart' as flutter_gallery_main;
+
+Finder byTooltip(WidgetTester tester, String message) {
+  return find.byWidgetPredicate((Widget widget) {
+    return widget is Tooltip && widget.message == message;
+  });
+}
+
+Finder findNavigationMenuButton(WidgetTester tester) {
+  return byTooltip(tester, 'Open navigation menu');
+}
+
+void main() {
+  TestWidgetsFlutterBinding binding =
+      TestWidgetsFlutterBinding.ensureInitialized();
+  if (binding is LiveTestWidgetsFlutterBinding) binding.allowAllFrames = true;
+
+  // Regression test for https://github.com/flutter/flutter/pull/5168
+  testWidgets('Pesto route management', (WidgetTester tester) async {
+    flutter_gallery_main
+        .main(); // builds the app and schedules a frame but doesn't trigger one
+    await tester.pump(); // see https://github.com/flutter/flutter/issues/1865
+    await tester.pump(); // triggers a frame
+
+    expect(find.text('Pesto'), findsOneWidget);
+    await tester.tap(find.text('Pesto'));
+    await tester.pump(); // Launch pesto
+    await tester.pump(const Duration(seconds: 1)); // transition is complete
+
+    Future<Null> tapDrawerItem(String title) async {
+      await tester.tap(findNavigationMenuButton(tester));
+      await tester.pump();
+      await tester.pump(const Duration(seconds: 1)); // drawer opening animation
+      await tester.tap(find.text(title));
+      await tester.pump();
+      await tester.pump(const Duration(seconds: 1)); // drawer closing animation
+      await tester.pump(); // maybe open a new page
+      return tester.pump(const Duration(seconds: 1)); // new page transition
+    }
+    await tapDrawerItem('Home');
+    await tapDrawerItem('Favorites');
+    await tapDrawerItem('Home');
+    await tapDrawerItem('Favorites');
+    await tapDrawerItem('Home');
+    await tapDrawerItem('Return to Gallery');
+
+    expect(find.text('Flutter gallery'), findsOneWidget);
+  });
+}

packages/flutter/lib/src/widgets/navigator.dart

@@ -161,6 +161,9 @@ class NavigatorObserver {
   void didPop(Route<dynamic> route, Route<dynamic> previousRoute) { }
 }
 
+/// Signature for the [Navigator.popUntil] predicate argument.
+typedef bool RoutePredicate(Route<dynamic> route);
+
 /// A widget that manages a set of child widgets with a stack discipline.
 ///
 /// Many apps have a navigator near the top of their widget hierarchy in order
@@ -243,10 +246,11 @@ class Navigator extends StatefulWidget {
     return Navigator.of(context).pop(result);
   }
 
-  /// Calls pop() repeatedly until the given route is the current route.
+  /// Calls [pop()] repeatedly until the predicate returns false.
-  /// If it is already the current route, nothing happens.
+  /// The predicate may be applied to the same route more than once if
-  static void popUntil(BuildContext context, Route<dynamic> targetRoute) {
+  /// [Route.willHandlePopInternally] is true.
-    Navigator.of(context).popUntil(targetRoute);
+  static void popUntil(BuildContext context, RoutePredicate predicate) {
+    Navigator.of(context).popUntil(predicate);
   }
 
   /// Whether the navigator that most tightly encloses the given context can be popped.
@@ -463,9 +467,8 @@ class NavigatorState extends State<Navigator> {
     return true;
   }
 
-  void popUntil(Route<dynamic> targetRoute) {
+  void popUntil(RoutePredicate predicate) {
-    assert(_history.contains(targetRoute));
+    while (!predicate(_history.last))
-    while (!targetRoute.isCurrent)
       pop();
   }
 

packages/flutter/lib/src/widgets/routes.dart

@@ -487,6 +487,17 @@ abstract class ModalRoute<T> extends TransitionRoute<T> with LocalHistoryRoute<T
     }
   }
 
+  /// Returns a predicate that's true if the route has the specified name and if
+  /// popping the route will not yield the same route, i.e. if the route's
+  /// [willHandlePopInternally] property is false.
+  ///
+  /// This function is typically used with [Navigator.popUntil()].
+  static RoutePredicate withName(String name) {
+    return (Route<dynamic> route) {
+      return !route.willHandlePopInternally
+        && route is ModalRoute && route.settings.name == name;
+    };
+  }
 
   // The API for subclasses to override - used by _ModalScope
 

packages/flutter/test/widget/routes_test.dart

@@ -11,7 +11,7 @@ final List<String> results = <String>[];
 
 Set<TestRoute> routes = new HashSet<TestRoute>();
 
-class TestRoute extends Route<String> {
+class TestRoute extends LocalHistoryRoute<String> {
   TestRoute(this.name);
   final String name;
 
@@ -329,7 +329,7 @@ void main() {
     await runNavigatorTest(
       tester,
       host,
-      () { host.popUntil(routeB); },
+      () { host.popUntil((Route<dynamic> route) => route == routeB); },
       <String>[
         'C: didPop null',
         'C: dispose',
@@ -341,4 +341,42 @@ void main() {
     expect(routes.isEmpty, isTrue);
     results.clear();
   });
+
+  testWidgets('Route localHistory - popUntil', (WidgetTester tester) async {
+    TestRoute routeA = new TestRoute('A');
+    routeA.addLocalHistoryEntry(new LocalHistoryEntry(
+      onRemove: () { routeA.log('onRemove 0'); }
+    ));
+    routeA.addLocalHistoryEntry(new LocalHistoryEntry(
+      onRemove: () { routeA.log('onRemove 1'); }
+    ));
+    GlobalKey<NavigatorState> navigatorKey = new GlobalKey<NavigatorState>();
+    await tester.pumpWidget(new Navigator(
+      key: navigatorKey,
+      onGenerateRoute: (_) => routeA
+    ));
+    NavigatorState host = navigatorKey.currentState;
+    await runNavigatorTest(
+      tester,
+      host,
+      () { host.popUntil((Route<dynamic> route) => !route.willHandlePopInternally); },
+      <String>[
+        'A: install',
+        'A: didPush',
+        'A: didChangeNext null',
+        'A: didPop null',
+        'A: onRemove 1',
+        'A: didPop null',
+        'A: onRemove 0',
+      ]
+    );
+
+    await runNavigatorTest(
+      tester,
+      host,
+      () { host.popUntil((Route<dynamic> route) => !route.willHandlePopInternally); },
+      <String>[
+      ]
+    );
+  });
 }