test: Port new Layout Tests

src/Uno.UI.RuntimeTests/MUX/Microsoft_UI_Xaml_Controls/Repeater/Common/Mocks/MockStackLayout.cs

@@ -0,0 +1,30 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License. See LICENSE in the project root for license information.
+
+using System;
+using Windows.Foundation;
+
+using Microsoft/* UWP don't rename */.UI.Xaml.Controls;
+
+namespace Microsoft.UI.Xaml.Tests.MUXControls.ApiTests.RepeaterTests.Common.Mocks;
+
+partial class MockStackLayout : StackLayout
+{
+	public Func<Size, VirtualizingLayoutContext, Size> MeasureLayoutFunc { get; set; }
+	public Func<Size, VirtualizingLayoutContext, Size> ArrangeLayoutFunc { get; set; }
+
+	public new void InvalidateMeasure()
+	{
+		base.InvalidateMeasure();
+	}
+
+	protected internal override Size MeasureOverride(VirtualizingLayoutContext context, Size availableSize)
+	{
+		return MeasureLayoutFunc != null ? MeasureLayoutFunc(availableSize, context) : default(Size);
+	}
+
+	protected internal override Size ArrangeOverride(VirtualizingLayoutContext context, Size finalSize)
+	{
+		return ArrangeLayoutFunc != null ? ArrangeLayoutFunc(finalSize, context) : default(Size);
+	}
+}

src/Uno.UI.RuntimeTests/MUX/Microsoft_UI_Xaml_Controls/Repeater/LayoutTests.cs

@@ -36,6 +36,10 @@
 using VirtualizingLayoutContext = Microsoft/* UWP don't rename */.UI.Xaml.Controls.VirtualizingLayoutContext;
 using ElementRealizationOptions = Microsoft/* UWP don't rename */.UI.Xaml.Controls.ElementRealizationOptions;
 using LayoutContext = Microsoft/* UWP don't rename */.UI.Xaml.Controls.LayoutContext;
+using UniformGridLayout = Microsoft/* UWP don't rename */.UI.Xaml.Controls.UniformGridLayout;
+using Microsoft.UI.Xaml.Media;
+using Private.Infrastructure;
+using System.Threading.Tasks;
 
 namespace Microsoft.UI.Xaml.Tests.MUXControls.ApiTests.RepeaterTests
 {
@@ -195,38 +199,6 @@ public void ValidateNonVirtualLayoutDoesNotGetMeasuredForViewportChanges()
 			});
 		}
 
-		[TestMethod]
-		[Ignore("UNO: Test does not pass yet with Uno https://github.com/unoplatform/uno/issues/4529")]
-		public void ValidateStackLayoutDoesNotRetainIncorrectMinorWidth()
-		{
-			RunOnUIThread.Execute(() =>
-			{
-				var repeater = new ItemsRepeater()
-				{
-					ItemsSource = Enumerable.Range(0, 1)
-				};
-
-				Content = new ScrollViewer()
-				{
-					Content = repeater,
-					Width = 400,
-				};
-
-				Content.UpdateLayout();
-
-				// Measure with large width.
-				repeater.Measure(new Size(600, 100));
-				Verify.AreEqual(600, repeater.DesiredSize.Width);
-				// Measure with smaller width again before arrange. 
-				// StackLayout has to pick up the smaller width for its extent.
-				repeater.Measure(new Size(300, 100));
-				Verify.AreEqual(300, repeater.DesiredSize.Width);
-
-				Content.UpdateLayout();
-				Verify.AreEqual(400, repeater.ActualWidth);
-			});
-		}
-
 		[TestMethod]
 #if __IOS__
 		[Ignore("UNO: Test does not pass yet with Uno (causes infinite layout cycle) https://github.com/unoplatform/uno/issues/4529")]
@@ -264,6 +236,253 @@ public void ValidateStackLayoutDisabledVirtualizationWithItemsRepeater()
 			});
 		}
 
+		[TestMethod]
+		public void VerifyStackLayoutCycleShortcut()
+		{
+			RunOnUIThread.Execute(() =>
+			{
+				int measureCount = 0;
+				int arrangeCount = 0;
+				var repeater = new ItemsRepeater();
+				var mockStackLayout = new MockStackLayout();
+
+				mockStackLayout.MeasureLayoutFunc = (size, context) =>
+				{
+					// Simulating variable sized children that cause
+					// the ItemsRepeater's layout to not settle.
+					// This would normally cause a layout cycle but the use
+					// of ItemsRepeater::m_stackLayoutMeasureCounter avoids it.
+					mockStackLayout.InvalidateMeasure();
+					measureCount++;
+					return new Size(100, 200 + measureCount);
+				};
+				mockStackLayout.ArrangeLayoutFunc = (size, context) =>
+				{
+					arrangeCount++;
+					return new Size(100, 200 + arrangeCount);
+				};
+
+				repeater.Layout = mockStackLayout;
+				repeater.ItemsSource = Enumerable.Range(0, 10);
+				repeater.ItemTemplate = GetDataTemplate("<Button Content='{Binding}' Height='200'/>");
+
+				Content = repeater;
+				Content.UpdateLayout();
+			});
+		}
+
+		[TestMethod]
+		[Ignore("Fails, itemsRepeaterOriginPoint.X is 0 at all times - https://github.com/unoplatform/uno/issues/8261")]
+		public async Task VerifyStackLayoutAlignment()
+		{
+			for (int horizontalAlignment = 0; horizontalAlignment <= 3; horizontalAlignment++)
+			{
+				Border border = null;
+				ItemsRepeater itemsRepeater = null;
+
+				RunOnUIThread.Execute(() =>
+				{
+					itemsRepeater = new ItemsRepeater()
+					{
+						HorizontalAlignment = (HorizontalAlignment)horizontalAlignment,
+						ItemsSource = Enumerable.Range(0, 2)
+					};
+
+					border = new Border()
+					{
+						Background = new SolidColorBrush(Colors.Azure),
+						Width = 400,
+						Height = 400,
+						Child = itemsRepeater
+					};
+
+					Content = border;
+				});
+
+				await TestServices.WindowHelper.WaitForIdle();
+
+				RunOnUIThread.Execute(() =>
+				{
+					Log.Comment($"ItemsRepeater.HorizontalAlignment set to {itemsRepeater.HorizontalAlignment}");
+					Log.Comment($"ItemsRepeater actual size: {itemsRepeater.ActualWidth}, {itemsRepeater.ActualHeight}");
+
+					Verify.AreEqual((HorizontalAlignment)horizontalAlignment, itemsRepeater.HorizontalAlignment);
+
+					GeneralTransform gt = itemsRepeater.TransformToVisual(border);
+					Point itemsRepeaterOriginPoint = new Point();
+					itemsRepeaterOriginPoint = gt.TransformPoint(itemsRepeaterOriginPoint);
+					Log.Comment($"ItemsRepeater position: {itemsRepeaterOriginPoint}");
+
+					for (int itemIndex = 0; itemIndex <= 1; itemIndex++)
+					{
+						FrameworkElement itemElement = itemsRepeater.TryGetElement(itemIndex) as FrameworkElement;
+						Verify.IsNotNull(itemElement);
+						var layoutBounds = LayoutInformation.GetLayoutSlot(itemElement);
+						Log.Comment($"ItemsRepeater child #{itemIndex} layout bounds: {layoutBounds}");
+					}
+
+					switch (itemsRepeater.HorizontalAlignment)
+					{
+						case HorizontalAlignment.Left:
+						case HorizontalAlignment.Stretch:
+							Verify.AreEqual(0, itemsRepeaterOriginPoint.X);
+							break;
+						case HorizontalAlignment.Center:
+							Verify.IsTrue(itemsRepeaterOriginPoint.X > 0);
+							Verify.AreEqual((border.ActualWidth - itemsRepeater.ActualWidth) / 2, itemsRepeaterOriginPoint.X);
+							break;
+						case HorizontalAlignment.Right:
+							Verify.IsTrue(itemsRepeaterOriginPoint.X > 0);
+							Verify.AreEqual(border.ActualWidth - itemsRepeater.ActualWidth, itemsRepeaterOriginPoint.X);
+							break;
+					}
+				});
+			}
+		}
+
+		[TestMethod]
+		public async Task VerifyUniformGridLayoutDoesntCrashWhenTryingToScrollToEnd()
+		{
+			ItemsRepeater repeater = null;
+			ScrollViewer scrollViewer = null;
+			RunOnUIThread.Execute(() =>
+			{
+				repeater = new ItemsRepeater
+				{
+					ItemsSource = Enumerable.Range(0, 1000).Select(i => new Border
+					{
+						Background = new SolidColorBrush(Colors.Blue),
+						Child = new TextBlock { Text = "#" + i }
+					}).ToArray(),
+					Layout = new UniformGridLayout
+					{
+						MinItemWidth = 100,
+						MinItemHeight = 40,
+						MinRowSpacing = 10,
+						MinColumnSpacing = 10
+					}
+				};
+				scrollViewer = new ScrollViewer { Content = repeater };
+				Content = scrollViewer;
+			});
+
+			await TestServices.WindowHelper.WaitForIdle();
+
+			RunOnUIThread.Execute(() =>
+			{
+				scrollViewer.ChangeView(0, repeater.ActualHeight, null);
+			});
+
+			await TestServices.WindowHelper.WaitForIdle();
+
+			RunOnUIThread.Execute(() =>
+			{
+				scrollViewer.ChangeView(0, 0, null);
+			});
+
+			await TestServices.WindowHelper.WaitForIdle();
+
+			// The test guards against an app crash, so this is enough to verify
+			Verify.IsTrue(true);
+		}
+
+		[TestMethod]
+#if !HAS_UNO_WINUI
+		[Ignore("Fails on UWP")]
+#endif
+		public async Task VerifyUniformGridLayoutDoesntHangWhenTryingToScrollToStart()
+		{
+			ItemsRepeater itemsRepeater = null;
+			ScrollViewer scrollViewer = null;
+			ManualResetEvent viewChanged = new ManualResetEvent(false);
+
+			RunOnUIThread.Execute(() =>
+			{
+				Log.Comment("Setting up UI.");
+
+				itemsRepeater = new ItemsRepeater
+				{
+					ItemsSource = Enumerable.Range(0, 10).Select(_ => Enumerable.Range(1, 6).ToList()).ToList()
+				};
+				itemsRepeater.ItemTemplate = XamlReader.Load(
+					@"<DataTemplate xmlns='http://schemas.microsoft.com/winfx/2006/xaml/presentation'>
+                          <ItemsRepeater ItemsSource='{Binding}'>
+                              <ItemsRepeater.Layout>
+                                  <UniformGridLayout
+                                      Orientation='Horizontal'
+                                      MinItemWidth='150.0'
+                                      MaximumRowsOrColumns='3'
+                                      MinRowSpacing='4'
+                                      MinColumnSpacing='4'
+                                      MinItemHeight='150.0'
+                                      ItemsStretch='Fill'/>
+                              </ItemsRepeater.Layout>
+                              <ItemsRepeater.ItemTemplate>
+                                  <DataTemplate>
+                                      <TextBlock Text='{Binding}'/>
+                                  </DataTemplate>
+                              </ItemsRepeater.ItemTemplate>
+                           </ItemsRepeater>
+                      </DataTemplate>") as DataTemplate;
+
+				scrollViewer = new ScrollViewer
+				{
+					Width = 500.0,
+					Height = 400.0,
+					Content = itemsRepeater
+				};
+				scrollViewer.ViewChanged += (sender, args) =>
+				{
+					Log.Comment($"ScrollViewer.ViewChanged raised for VerticalOffset '{scrollViewer.VerticalOffset}'.");
+
+					if (!args.IsIntermediate)
+					{
+						Log.Comment("ScrollViewer.ChangeView completed.");
+
+						viewChanged.Set();
+					}
+				};
+
+				Content = scrollViewer;
+				Content.UpdateLayout();
+			});
+
+			await TestServices.WindowHelper.WaitForIdle();
+
+			Log.Comment("Scrolling to the bottom in 16 jumps...");
+
+			for (int i = 1; i <= 16; i++)
+			{
+				RunOnUIThread.Execute(() =>
+				{
+					Log.Comment($"Jumping to VerticalOffset '{scrollViewer.ScrollableHeight * i / 16}'.");
+
+					scrollViewer.ChangeView(null, scrollViewer.ScrollableHeight * i / 16, null, true);
+				});
+
+				Verify.IsTrue(viewChanged.WaitOne());
+				viewChanged.Reset();
+				await TestServices.WindowHelper.WaitForIdle();
+			}
+
+			Log.Comment("Scrolling to the top in 16 jumps...");
+
+			for (int i = 15; i >= 0; i--)
+			{
+				RunOnUIThread.Execute(() =>
+				{
+					Log.Comment($"Jumping to VerticalOffset '{scrollViewer.ScrollableHeight * i / 16}'.");
+
+					scrollViewer.ChangeView(null, scrollViewer.ScrollableHeight * i / 16, null, true);
+				});
+
+				Verify.IsTrue(viewChanged.WaitOne());
+				viewChanged.Reset();
+				await TestServices.WindowHelper.WaitForIdle();
+			}
+		}
+
+
 		private ItemsRepeaterScrollHost CreateAndInitializeRepeater(
 		   object itemsSource,
 		   VirtualizingLayout layout,