Avalonia/tests/Avalonia.Controls.UnitTests/VirtualizingStackPanelTests.cs

////using System;
////using System.Collections.Generic;
////using Avalonia.Controls.Primitives;
////using Avalonia.Input;
////using Avalonia.LogicalTree;
////using Moq;
////using Xunit;

////namespace Avalonia.Controls.UnitTests
////{
////    public class VirtualizingStackPanelTests
////    {
////        public class Vertical
////        {
////            [Fact]
////            public void Measure_Invokes_Controller_UpdateControls()
////            {
////                var target = new VirtualizingStackPanel();
////                var controller = new Mock<IVirtualizingController>();

////                ((IVirtualizingPanel)target).Controller = controller.Object;
////                target.Measure(new Size(100, 100));

////                controller.Verify(x => x.UpdateControls(), Times.Once());
////            }

////            [Fact]
////            public void Measure_Invokes_Controller_UpdateControls_If_AvailableSize_Changes()
////            {
////                var target = new VirtualizingStackPanel();
////                var controller = new Mock<IVirtualizingController>();

////                ((IVirtualizingPanel)target).Controller = controller.Object;
////                target.Measure(new Size(100, 100));
////                target.InvalidateMeasure();
////                target.Measure(new Size(100, 100));
////                target.InvalidateMeasure();
////                target.Measure(new Size(100, 101));

////                controller.Verify(x => x.UpdateControls(), Times.Exactly(2));
////            }

////            [Fact]
////            public void Measure_Does_Not_Invoke_Controller_UpdateControls_If_AvailableSize_Is_The_Same()
////            {
////                var target = new VirtualizingStackPanel();
////                var controller = new Mock<IVirtualizingController>();

////                ((IVirtualizingPanel)target).Controller = controller.Object;
////                target.Measure(new Size(100, 100));
////                target.InvalidateMeasure();
////                target.Measure(new Size(100, 100));

////                controller.Verify(x => x.UpdateControls(), Times.Once());
////            }

////            [Fact]
////            public void Measure_Invokes_Controller_UpdateControls_If_AvailableSize_Is_The_Same_After_ForceInvalidateMeasure()
////            {
////                var target = new VirtualizingStackPanel();
////                var controller = new Mock<IVirtualizingController>();

////                ((IVirtualizingPanel)target).Controller = controller.Object;
////                target.Measure(new Size(100, 100));
////                ((IVirtualizingPanel)target).ForceInvalidateMeasure();
////                target.Measure(new Size(100, 100));

////                controller.Verify(x => x.UpdateControls(), Times.Exactly(2));
////            }

////            [Fact]
////            public void Arrange_Invokes_Controller_UpdateControls()
////            {
////                var target = new VirtualizingStackPanel();
////                var controller = new Mock<IVirtualizingController>();

////                ((IVirtualizingPanel)target).Controller = controller.Object;
////                target.Measure(new Size(100, 100));
////                target.Arrange(new Rect(0, 0, 110, 110));

////                controller.Verify(x => x.UpdateControls(), Times.Exactly(2));
////            }

////            [Fact]
////            public void Reports_IsFull_False_Until_Measure_Height_Is_Reached()
////            {
////                var target = new VirtualizingStackPanel();
////                var vp = (IVirtualizingPanel)target;

////                target.Measure(new Size(100, 100));

////                Assert.Equal(new Size(0, 0), target.DesiredSize);
////                Assert.Equal(new Size(0, 0), target.Bounds.Size);

////                Assert.False(vp.IsFull);
////                Assert.Equal(0, vp.OverflowCount);
////                target.Children.Add(new Canvas { Width = 50, Height = 50 });
////                Assert.False(vp.IsFull);
////                Assert.Equal(0, vp.OverflowCount);
////                target.Children.Add(new Canvas { Width = 50, Height = 50 });
////                Assert.True(vp.IsFull);
////                Assert.Equal(0, vp.OverflowCount);
////            }

////            [Fact]
////            public void Reports_Overflow_After_Arrange()
////            {
////                var target = new VirtualizingStackPanel();
////                var vp = (IVirtualizingPanel)target;

////                target.Measure(new Size(100, 100));
////                target.Arrange(new Rect(target.DesiredSize));

////                Assert.Equal(new Size(0, 0), target.Bounds.Size);

////                target.Children.Add(new Canvas { Width = 50, Height = 50 });
////                target.Children.Add(new Canvas { Width = 50, Height = 50 });
////                target.Children.Add(new Canvas { Width = 50, Height = 50 });
////                target.Children.Add(new Canvas { Width = 50, Height = 50 });
////                Assert.Equal(0, vp.OverflowCount);

////                target.Measure(new Size(100, 100));
////                target.Arrange(new Rect(target.DesiredSize));

////                Assert.Equal(2, vp.OverflowCount);
////            }

////            [Fact]
////            public void Reports_Correct_Overflow_During_Arrange()
////            {
////                var target = new VirtualizingStackPanel();
////                var vp = (IVirtualizingPanel)target;
////                var controller = new Mock<IVirtualizingController>();
////                var called = false;

////                target.Children.Add(new Canvas { Width = 50, Height = 50 });
////                target.Children.Add(new Canvas { Width = 50, Height = 52 });
////                target.Measure(new Size(100, 100));

////                controller.Setup(x => x.UpdateControls()).Callback(() =>
////                {
////                    Assert.Equal(2, vp.PixelOverflow);
////                    Assert.Equal(0, vp.OverflowCount);
////                    called = true;
////                });

////                vp.Controller = controller.Object;
////                target.Arrange(new Rect(target.DesiredSize));

////                Assert.True(called);
////            }

////            [Fact]
////            public void Reports_PixelOverflow_After_Arrange()
////            {
////                var target = new VirtualizingStackPanel();

////                target.Children.Add(new Canvas { Width = 50, Height = 50 });
////                target.Children.Add(new Canvas { Width = 50, Height = 52 });

////                target.Measure(new Size(100, 100));
////                target.Arrange(new Rect(target.DesiredSize));

////                Assert.Equal(2, ((IVirtualizingPanel)target).PixelOverflow);
////            }

////            [Fact]
////            public void Reports_PixelOverflow_After_Arrange_Smaller_Than_Measure()
////            {
////                var target = new VirtualizingStackPanel();

////                target.Children.Add(new Canvas { Width = 50, Height = 50 });
////                target.Children.Add(new Canvas { Width = 50, Height = 52 });

////                target.Measure(new Size(100, 100));
////                target.Arrange(new Rect(0, 0, 50, 50));

////                Assert.Equal(52, ((IVirtualizingPanel)target).PixelOverflow);
////            }

////            [Fact]
////            public void Reports_PixelOverflow_With_PixelOffset()
////            {
////                var target = new VirtualizingStackPanel();
////                var vp = (IVirtualizingPanel)target;

////                target.Children.Add(new Canvas { Width = 50, Height = 50 });
////                target.Children.Add(new Canvas { Width = 50, Height = 52 });
////                vp.PixelOffset = 2;

////                target.Measure(new Size(100, 100));
////                target.Arrange(new Rect(target.DesiredSize));

////                Assert.Equal(2, vp.PixelOverflow);
////            }

////            [Fact]
////            public void PixelOffset_Can_Be_More_Than_Child_Without_Affecting_IsFull()
////            {
////                var target = new VirtualizingStackPanel();
////                var vp = (IVirtualizingPanel)target;

////                target.Children.Add(new Canvas { Width = 50, Height = 50 });
////                target.Children.Add(new Canvas { Width = 50, Height = 52 });
////                vp.PixelOffset = 55;

////                target.Measure(new Size(100, 100));
////                target.Arrange(new Rect(target.DesiredSize));

////                Assert.Equal(55, vp.PixelOffset);
////                Assert.Equal(2, vp.PixelOverflow);
////                Assert.True(vp.IsFull);
////            }

////            [Fact]
////            public void Passes_Navigation_Request_To_ILogicalScrollable_Parent()
////            {
////                var target = new VirtualizingStackPanel();
////                var presenter = new TestPresenter { Child = target };
////                var from = new Canvas();

////                ((INavigableContainer)target).GetControl(NavigationDirection.Next, from, false);

////                Assert.Equal(1, presenter.NavigationRequests.Count);
////                Assert.Equal((NavigationDirection.Next, from), presenter.NavigationRequests[0]);
////            }

////            private class TestPresenter : Decorator, ILogicalScrollable
////            {
////                public bool CanHorizontallyScroll { get; set; }
////                public bool CanVerticallyScroll { get; set; }
////                public bool IsLogicalScrollEnabled => true;
////                public Size ScrollSize { get; }
////                public Size PageScrollSize { get; }
////                public Size Extent { get; }
////                public Vector Offset { get; set; }
////                public Size Viewport { get; }

////                public event EventHandler ScrollInvalidated;

////                public List<(NavigationDirection, Control)> NavigationRequests { get; } = new();

////                public bool BringIntoView(Control target, Rect targetRect)
////                {
////                    throw new NotImplementedException();
////                }

////                public Control GetControlInDirection(NavigationDirection direction, Control from)
////                {
////                    NavigationRequests.Add((direction, from));
////                    return null;
////                }

////                public void RaiseScrollInvalidated(EventArgs e)
////                {
////                    throw new NotImplementedException();
////                }
////            }
////        }
////    }
////}