Add tests for memory leak

src/Samples/README.md

@@ -0,0 +1,5 @@
+# Note
+
+The WinUIDesktopSample and WinUIDesktopSamplePackage contain repro scenarios for the memory leak we addressed around version 1.1.4.
+These scenarios should be moved out of samples and into our unit test suite, so we can have automated verification.
+Until we port ObjectLifetimeTests into our unit tests, these samples serve as a way to check we have not regressed any scenarios.

src/Samples/WinUIDesktopSample/App.xaml

@@ -3,6 +3,12 @@
              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
              >
     <Application.Resources>
-
+        <ResourceDictionary>
+            <ResourceDictionary.MergedDictionaries>
+                <XamlControlsResources xmlns="using:Microsoft.UI.Xaml.Controls" />
+                <!-- Other merged dictionaries here -->
+            </ResourceDictionary.MergedDictionaries>
+            <!-- Other app resources here -->
+        </ResourceDictionary>
     </Application.Resources>
 </Application>

src/Samples/WinUIDesktopSample/App.xaml.cs

@@ -1,13 +1,7 @@
-using System;
-using System.Collections.Generic;
-using System.Configuration;
-using System.Data;
-using System.Linq;
-using System.Threading.Tasks;
-using Microsoft.UI.Xaml;
-using Microsoft.UI.Xaml.Controls;
-using Microsoft.UI.Xaml.Media;
-using Windows.Web.Http;
+using Microsoft.UI.Xaml;
+using System;
+using Windows.ApplicationModel;
+
 
 namespace WinUIDesktopSample
 {
@@ -16,44 +10,39 @@ namespace WinUIDesktopSample
     /// </summary>
     public partial class App : Application
     {
+        private Window myWindow;
+
         public App()
         {
+            WinRT.ComWrappersSupport.RegisterProjectionAssembly(typeof(App).Assembly);
+            this.InitializeComponent();
+            this.Suspending += OnSuspending;
         }
 
-        Window myWindow;
-        protected override void OnLaunched(LaunchActivatedEventArgs args)
+        public static void Navigate(Type pageType)
         {
-            var value = DependencyProperty.UnsetValue;
-            var button = new Button
-            {
-                Content = "Click me to load MainPage",
-                HorizontalAlignment = HorizontalAlignment.Center,
-                VerticalAlignment = VerticalAlignment.Center
-            };
-            button.Click += Button_Click;
-            var window = new Microsoft.UI.Xaml.Window
-            {
-                Content = button
-            };
-
-            window.Activate();
-
-            myWindow = window;
+            App app = (App)Current;
+            MainWindow mainWindow = (MainWindow)app.myWindow;
+            mainWindow.Frame.Navigate(pageType);
         }
 
-        private void Button_Click(object sender, RoutedEventArgs e)
+        protected override void OnLaunched(Microsoft.UI.Xaml.LaunchActivatedEventArgs args)
         {
-            myWindow.Content = new MainPage();
+            myWindow = new MainWindow();
+            myWindow.Activate();
         }
-    }
 
-    public static class Program
-    {
-        static void Main(string[] args)
-        {
-            WinRT.ComWrappersSupport.InitializeComWrappers();
 
-            Microsoft.UI.Xaml.Application.Start((e) => new App());
+        /// <summary>
+        /// Invoked when application execution is being suspended.  Application state is saved
+        /// without knowing whether the application will be terminated or resumed with the contents
+        /// of memory still intact.
+        /// </summary>
+        /// <param name="sender">The source of the suspend request.</param>
+        /// <param name="e">Details about the suspend request.</param>
+        private void OnSuspending(object sender, SuspendingEventArgs e)
+        {
+            // Save application state and stop any background activity
         }
     }
 }

src/Samples/WinUIDesktopSample/FirstPage.xaml

@@ -0,0 +1,16 @@
+<Page
+    x:Class="WinUIDesktopSample.FirstPage"
+    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:local="using:WinUIDesktopSample"
+    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+    mc:Ignorable="d"
+    Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">
+
+    <StackPanel>
+        <Button Content="Navigate to SecondPage" Click="Button_Click" />
+        <TextBlock x:Name="Status" />
+        <ListView x:Name="TheListView" />
+    </StackPanel>
+</Page>

src/Samples/WinUIDesktopSample/FirstPage.xaml.cs

@@ -0,0 +1,53 @@
+using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Controls;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+// To learn more about WinUI, the WinUI project structure,
+// and more about our project templates, see: http://aka.ms/winui-project-info.
+
+namespace WinUIDesktopSample
+{
+    public class LeakedObject : Page
+    {
+        byte[] bytes = new byte[10_000_000];
+    };
+    /// <summary>
+    /// An empty page that can be used on its own or navigated to within a Frame.
+    /// </summary>
+    public sealed partial class FirstPage : Page
+    {
+        private static List<WeakReference> instances = new List<WeakReference>();
+
+        public FirstPage()
+        {
+            this.InitializeComponent();
+
+            this.TheListView.ItemsSource = GetItems();
+
+            GC.Collect(2, GCCollectionMode.Forced, true);
+            GC.WaitForPendingFinalizers();
+            var collected = instances.Count((WeakReference wr) => !wr.IsAlive);
+            var leaked = instances.Count((WeakReference wr) => wr.IsAlive);
+            System.Diagnostics.Debug.WriteLine("FirstPage instances: ");
+            System.Diagnostics.Debug.WriteLine("  collected: " + collected);
+            System.Diagnostics.Debug.WriteLine("  leaked: " + leaked);
+            this.Status.Text = "FirstPage instances: collected: " + collected + "  leaked: " + leaked;
+            instances.Add(new WeakReference(this));
+        }
+
+        public IEnumerable<string> GetItems()
+        {
+            for (int i = 0; i < 1000; i++)
+            {
+                yield return "Item " + (i + 1);
+            }
+        }
+
+        private void Button_Click(object sender, RoutedEventArgs e)
+        {
+            App.Navigate(typeof(SecondPage));
+        }
+    }
+}

src/Samples/WinUIDesktopSample/MainPage.xaml

@@ -5,8 +5,28 @@
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         xmlns:local="WinUIDesktopSample"
         mc:Ignorable="d"
-        Height="450" Width="800">
-    <Grid>
-        <TextBlock HorizontalAlignment="Center" VerticalAlignment="Center" Text="Hello from WinUI Desktop!" x:Name="text"/>
-    </Grid>
+        Height="600" Width="800">
+
+
+    <StackPanel>
+        <Button x:Name="Button1" Content="Aggregation" Click="Button1Click" />
+        <Button x:Name="Button2" Content="AggregationAndProperty" Click="Button2Click" />
+        <Button x:Name="Button3" Content="AggregationAndEvent" Click="Button3Click" />
+        <Button x:Name="Button4" Content="Button" Click="Button4Click" />
+        <Button x:Name="Button5" Content="ButtonAndProperty" Click="Button5Click" />
+        <Button x:Name="Button6" Content="ButtonAndEvent" Click="Button6Click" />
+        <Button x:Name="Button7" Content="XamlMarkup-PageWithButton" Click="Button7Click" />
+        <Button x:Name="Button8" Content="XamlCode-PageWithButton" Click="Button8Click" />
+        <Button x:Name="Button9" Content="StrongButton" Click="Button9Click" />
+        <TextBlock x:Name="Build" Text="" />
+        <Button x:Name="WithoutCapture" Click="WithoutCapture_Click">Grid and handler without capture</Button>
+        <Button x:Name="WithCapture" Click="WithCapture_Click">Grid and handler with capture</Button>
+        <Button x:Name="DerivedWithoutCapture" Click="DerivedWithoutCapture_Click">Derived Grid and handler without capture</Button>
+        <Button x:Name="DerivedWithCapture" Click="DerivedWithCapture_Click">Derived Grid and handler with capture</Button>
+        <Button x:Name="Alloc" Click="Alloc_Click">1. Allocate various aggregates</Button>
+        <Button x:Name="Check" Click="Check_Click">2. Check for leaks of aggregates</Button>
+        <Button x:Name="NavigateButton" Click="Navigate_Click">Navigate to first page</Button>
+        <TextBlock x:Name="Status" Text="(click a button)" />
+    </StackPanel>
+
 </Page>