Avalonia/tests/Avalonia.Layout.UnitTests/LayoutManagerTests.cs

// Copyright (c) The Avalonia Project. All rights reserved.
// Licensed under the MIT license. See licence.md file in the project root for full license information.

using Avalonia.Controls;
using Xunit;

namespace Avalonia.Layout.UnitTests
{
    public class LayoutManagerTests
    {
        [Fact]
        public void Invalidating_Child_Should_Remeasure_Parent()
        {
            var layoutManager = new LayoutManager();

            using (AvaloniaLocator.EnterScope())
            {
                AvaloniaLocator.CurrentMutable.Bind<ILayoutManager>().ToConstant(layoutManager);

                Border border;
                StackPanel panel;

                var root = new TestLayoutRoot
                {
                    Child = panel = new StackPanel
                    {
                        Children = new Controls.Controls
                    {
                        (border = new Border())
                    }
                    }
                };

                layoutManager.ExecuteInitialLayoutPass(root);
                Assert.Equal(new Size(0, 0), root.DesiredSize);

                border.Width = 100;
                border.Height = 100;

                layoutManager.ExecuteLayoutPass();
                Assert.Equal(new Size(100, 100), panel.DesiredSize);
            }                
        }
    }
}