Add SharedSizeScope tests from #1945

Fix IsSharedSizeScope/PrivateSharedSizeScope so that it can be
set on non-`Grid` controls.

src/Avalonia.Controls/Grid/Grid.cs

@@ -177,7 +177,7 @@ namespace Avalonia.Controls
         static Grid()
         {
             ShowGridLinesProperty.Changed.AddClassHandler<Grid>(OnShowGridLinesPropertyChanged);
-            IsSharedSizeScopeProperty.Changed.AddClassHandler<Grid>(IsSharedSizeScopePropertyChanged);
+            IsSharedSizeScopeProperty.Changed.AddClassHandler<Control>(IsSharedSizeScopePropertyChanged);
             BoundsProperty.Changed.AddClassHandler<Grid>(BoundsPropertyChanged);
 
             AffectsParentMeasure<Grid>(ColumnProperty, ColumnSpanProperty, RowProperty, RowSpanProperty);
@@ -196,20 +196,32 @@ namespace Avalonia.Controls
                 grid._definitionsU[i].OnUserSizePropertyChanged(arg2);
             for (int i = 0; i < grid._definitionsV.Length; i++)
                 grid._definitionsV[i].OnUserSizePropertyChanged(arg2);
+
+            UpdateSharedSizeScopes(grid);
         }
 
-        private static void IsSharedSizeScopePropertyChanged(Grid grid, AvaloniaPropertyChangedEventArgs e)
+        private static void IsSharedSizeScopePropertyChanged(Control control, AvaloniaPropertyChangedEventArgs e)
         {
             if ((bool)e.NewValue)
             {
-                grid.PrivateSharedSizeScope = new SharedSizeScope();
+                control.SetValue(Grid.PrivateSharedSizeScopeProperty, new SharedSizeScope());
             }
             else
             {
-                grid.PrivateSharedSizeScope = null;
+                control.SetValue(Grid.PrivateSharedSizeScopeProperty, null);
             }
         }
 
+        static void UpdateSharedSizeScopes(Grid grid)
+        {
+            for (int i = 0; i < grid._definitionsU.Length; i++)
+                if (grid._definitionsU[i].SharedSizeGroup != null)
+                    grid._definitionsU[i].UpdateSharedScope();
+            for (int i = 0; i < grid._definitionsV.Length; i++)
+                if (grid._definitionsV[i].SharedSizeGroup != null)
+                    grid._definitionsV[i].UpdateSharedScope();
+        }
+
         /// <summary>
         /// Defines the Column attached property.
         /// </summary>
@@ -242,7 +254,7 @@ namespace Avalonia.Controls
             AvaloniaProperty.RegisterAttached<Grid, Control, bool>("IsSharedSizeScope", false);
 
         internal static readonly AttachedProperty<SharedSizeScope> PrivateSharedSizeScopeProperty =
-            AvaloniaProperty.RegisterAttached<Grid, Control, SharedSizeScope>("PrivateSharedSizeScope", null, inherits: true);
+            AvaloniaProperty.RegisterAttached<Grid, Control, SharedSizeScope>("&&PrivateSharedSizeScope", null, inherits: true);
 
         /// <summary>
         /// Defines the <see cref="ShowGridLines"/> property.
@@ -614,6 +626,7 @@ namespace Avalonia.Controls
             {
             }
 
+            UpdateSharedSizeScopes(this);
             return (gridDesiredSize);
         }
 
@@ -688,6 +701,7 @@ namespace Avalonia.Controls
                 RowDefinitions[i].ActualHeight = GetFinalRowDefinitionHeight(i);
             }
 
+            UpdateSharedSizeScopes(this);
             return (arrangeSize);
         }
 

tests/Avalonia.Controls.UnitTests/GridTests.cs

@@ -1,6 +1,9 @@
 // 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 System.Collections.Generic;
+using System.Linq;
+using Avalonia.UnitTests;
 using Xunit;
 
 namespace Avalonia.Controls.UnitTests
@@ -179,5 +182,268 @@ namespace Avalonia.Controls.UnitTests
 
             Assert.False(target.IsMeasureValid);
         }
+
+        [Fact]
+        public void All_Descendant_Grids_Are_Registered_When_Added_After_Setting_Scope()
+        {
+            var grids = new[] { new Grid(), new Grid(), new Grid() };
+            var scope = new Panel();
+            scope.Children.AddRange(grids);
+
+            var root = new TestRoot();
+            root.SetValue(Grid.IsSharedSizeScopeProperty, true);
+            root.Child = scope;
+
+            Assert.All(grids, g => Assert.True(g.PrivateSharedSizeScope != null));
+        }
+
+        [Fact]
+        public void All_Descendant_Grids_Are_Registered_When_Setting_Scope()
+        {
+            var grids = new[] { new Grid(), new Grid(), new Grid() };
+            var scope = new Panel();
+            scope.Children.AddRange(grids);
+
+            var root = new TestRoot();
+            root.Child = scope;
+            root.SetValue(Grid.IsSharedSizeScopeProperty, true);
+
+            Assert.All(grids, g => Assert.True(g.PrivateSharedSizeScope != null));
+        }
+
+        [Fact]
+        public void All_Descendant_Grids_Are_Unregistered_When_Resetting_Scope()
+        {
+            var grids = new[] { new Grid(), new Grid(), new Grid() };
+            var scope = new Panel();
+            scope.Children.AddRange(grids);
+
+            var root = new TestRoot();
+            root.SetValue(Grid.IsSharedSizeScopeProperty, true);
+            root.Child = scope;
+
+            Assert.All(grids, g => Assert.True(g.PrivateSharedSizeScope != null));
+            root.SetValue(Grid.IsSharedSizeScopeProperty, false);
+            Assert.All(grids, g => Assert.False(g.PrivateSharedSizeScope != null));
+            Assert.Equal(null, root.GetValue(Grid.PrivateSharedSizeScopeProperty));
+        }
+
+        [Fact]
+        public void Size_Is_Propagated_Between_Grids()
+        {
+            var grids = new[] { CreateGrid("A", null), CreateGrid(("A", new GridLength(30)), (null, new GridLength())) };
+            var scope = new Panel();
+            scope.Children.AddRange(grids);
+
+            var root = new TestRoot();
+            root.SetValue(Grid.IsSharedSizeScopeProperty, true);
+            root.Child = scope;
+
+            root.Measure(new Size(50, 50));
+            root.Arrange(new Rect(new Point(), new Point(50, 50)));
+            Assert.Equal(30, grids[0].ColumnDefinitions[0].ActualWidth);
+        }
+
+        [Fact]
+        public void Size_Propagation_Is_Constrained_To_Innermost_Scope()
+        {
+            var grids = new[] { CreateGrid("A", null), CreateGrid(("A", new GridLength(30)), (null, new GridLength())) };
+            var innerScope = new Panel();
+            innerScope.Children.AddRange(grids);
+            innerScope.SetValue(Grid.IsSharedSizeScopeProperty, true);
+
+            var outerGrid = CreateGrid(("A", new GridLength(0)));
+            var outerScope = new Panel();
+            outerScope.Children.AddRange(new[] { outerGrid, innerScope });
+
+            var root = new TestRoot();
+            root.SetValue(Grid.IsSharedSizeScopeProperty, true);
+            root.Child = outerScope;
+
+            root.Measure(new Size(50, 50));
+            root.Arrange(new Rect(new Point(), new Point(50, 50)));
+            Assert.Equal(0, outerGrid.ColumnDefinitions[0].ActualWidth);
+        }
+
+        [Fact]
+        public void Size_Is_Propagated_Between_Rows_And_Columns()
+        {
+            var grid = new Grid
+            {
+                ColumnDefinitions = new ColumnDefinitions("*,30"),
+                RowDefinitions = new RowDefinitions("*,10")
+            };
+
+            grid.ColumnDefinitions[1].SharedSizeGroup = "A";
+            grid.RowDefinitions[1].SharedSizeGroup = "A";
+
+            var root = new TestRoot();
+            root.Child = grid;
+            root.SetValue(Grid.IsSharedSizeScopeProperty, true);
+            root.Measure(new Size(50, 50));
+            root.Arrange(new Rect(new Point(), new Point(50, 50)));
+            Assert.Equal(30, grid.RowDefinitions[1].ActualHeight);
+        }
+
+        [Fact]
+        public void Size_Group_Changes_Are_Tracked()
+        {
+            var grids = new[] {
+                CreateGrid((null, new GridLength(0, GridUnitType.Auto)), (null, new GridLength())),
+                CreateGrid(("A", new GridLength(30)), (null, new GridLength())) };
+            var scope = new Panel();
+            scope.Children.AddRange(grids);
+
+            var root = new TestRoot();
+            root.SetValue(Grid.IsSharedSizeScopeProperty, true);
+            root.Child = scope;
+
+            root.Measure(new Size(50, 50));
+            root.Arrange(new Rect(new Point(), new Point(50, 50)));
+            Assert.Equal(0, grids[0].ColumnDefinitions[0].ActualWidth);
+
+            grids[0].ColumnDefinitions[0].SharedSizeGroup = "A";
+
+            root.Measure(new Size(51, 51));
+            root.Arrange(new Rect(new Point(), new Point(51, 51)));
+            Assert.Equal(30, grids[0].ColumnDefinitions[0].ActualWidth);
+
+            grids[0].ColumnDefinitions[0].SharedSizeGroup = null;
+
+            root.Measure(new Size(52, 52));
+            root.Arrange(new Rect(new Point(), new Point(52, 52)));
+            Assert.Equal(0, grids[0].ColumnDefinitions[0].ActualWidth);
+        }
+
+        [Fact]
+        public void Collection_Changes_Are_Tracked()
+        {
+            var grid = CreateGrid(
+                ("A", new GridLength(20)),
+                ("A", new GridLength(30)),
+                ("A", new GridLength(40)),
+                (null, new GridLength()));
+
+            var scope = new Panel();
+            scope.Children.Add(grid);
+
+            var root = new TestRoot();
+            root.SetValue(Grid.IsSharedSizeScopeProperty, true);
+            root.Child = scope;
+
+            grid.Measure(new Size(200, 200));
+            grid.Arrange(new Rect(new Point(), new Point(200, 200)));
+            Assert.All(grid.ColumnDefinitions.Where(cd => cd.SharedSizeGroup == "A"), cd => Assert.Equal(40, cd.ActualWidth));
+
+            grid.ColumnDefinitions.RemoveAt(2);
+
+            grid.Measure(new Size(200, 200));
+            grid.Arrange(new Rect(new Point(), new Point(200, 200)));
+            Assert.All(grid.ColumnDefinitions.Where(cd => cd.SharedSizeGroup == "A"), cd => Assert.Equal(30, cd.ActualWidth));
+
+            grid.ColumnDefinitions.Insert(1, new ColumnDefinition { Width = new GridLength(35), SharedSizeGroup = "A" });
+
+            grid.Measure(new Size(200, 200));
+            grid.Arrange(new Rect(new Point(), new Point(200, 200)));
+            Assert.All(grid.ColumnDefinitions.Where(cd => cd.SharedSizeGroup == "A"), cd => Assert.Equal(35, cd.ActualWidth));
+
+            grid.ColumnDefinitions[1] = new ColumnDefinition { Width = new GridLength(10), SharedSizeGroup = "A" };
+
+            grid.Measure(new Size(200, 200));
+            grid.Arrange(new Rect(new Point(), new Point(200, 200)));
+            Assert.All(grid.ColumnDefinitions.Where(cd => cd.SharedSizeGroup == "A"), cd => Assert.Equal(30, cd.ActualWidth));
+
+            grid.ColumnDefinitions[1] = new ColumnDefinition { Width = new GridLength(50), SharedSizeGroup = "A" };
+
+            grid.Measure(new Size(200, 200));
+            grid.Arrange(new Rect(new Point(), new Point(200, 200)));
+            Assert.All(grid.ColumnDefinitions.Where(cd => cd.SharedSizeGroup == "A"), cd => Assert.Equal(50, cd.ActualWidth));
+        }
+
+        [Fact]
+        public void Size_Priorities_Are_Maintained()
+        {
+            var sizers = new List<Control>();
+            var grid = CreateGrid(
+                ("A", new GridLength(20)),
+                ("A", new GridLength(20, GridUnitType.Auto)),
+                ("A", new GridLength(1, GridUnitType.Star)),
+                ("A", new GridLength(1, GridUnitType.Star)),
+                (null, new GridLength()));
+            for (int i = 0; i < 3; i++)
+                sizers.Add(AddSizer(grid, i, 6 + i * 6));
+            var scope = new Panel();
+            scope.Children.Add(grid);
+
+            var root = new TestRoot();
+            root.SetValue(Grid.IsSharedSizeScopeProperty, true);
+            root.Child = scope;
+
+            grid.Measure(new Size(100, 100));
+            grid.Arrange(new Rect(new Point(), new Point(100, 100)));
+            // all in group are equal to the first fixed column
+            Assert.All(grid.ColumnDefinitions.Where(cd => cd.SharedSizeGroup == "A"), cd => Assert.Equal(20, cd.ActualWidth));
+
+            grid.ColumnDefinitions[0].SharedSizeGroup = null;
+
+            grid.Measure(new Size(100, 100));
+            grid.Arrange(new Rect(new Point(), new Point(100, 100)));
+            // all in group are equal to width (MinWidth) of the sizer in the second column
+            Assert.All(grid.ColumnDefinitions.Where(cd => cd.SharedSizeGroup == "A"), cd => Assert.Equal(6 + 1 * 6, cd.ActualWidth));
+
+            grid.ColumnDefinitions[1].SharedSizeGroup = null;
+
+            grid.Measure(new Size(double.PositiveInfinity, 100));
+            grid.Arrange(new Rect(new Point(), new Point(100, 100)));
+            // with no constraint star columns default to the MinWidth of the sizer in the column
+            Assert.All(grid.ColumnDefinitions.Where(cd => cd.SharedSizeGroup == "A"), cd => Assert.Equal(6 + 2 * 6, cd.ActualWidth));
+        }
+
+        // grid creators
+        private Grid CreateGrid(params string[] columnGroups)
+        {
+            return CreateGrid(columnGroups.Select(s => (s, ColumnDefinition.WidthProperty.GetDefaultValue(typeof(ColumnDefinition)))).ToArray());
+        }
+
+        private Grid CreateGrid(params (string name, GridLength width)[] columns)
+        {
+            return CreateGrid(columns.Select(c =>
+                (c.name, c.width, ColumnDefinition.MinWidthProperty.GetDefaultValue(typeof(ColumnDefinition)))).ToArray());
+        }
+
+        private Grid CreateGrid(params (string name, GridLength width, double minWidth)[] columns)
+        {
+            return CreateGrid(columns.Select(c =>
+                (c.name, c.width, c.minWidth, ColumnDefinition.MaxWidthProperty.GetDefaultValue(typeof(ColumnDefinition)))).ToArray());
+        }
+
+        private Grid CreateGrid(params (string name, GridLength width, double minWidth, double maxWidth)[] columns)
+        {
+            var columnDefinitions = new ColumnDefinitions();
+
+            columnDefinitions.AddRange(
+                    columns.Select(c => new ColumnDefinition
+                    {
+                        SharedSizeGroup = c.name,
+                        Width = c.width,
+                        MinWidth = c.minWidth,
+                        MaxWidth = c.maxWidth
+                    })
+                );
+            var grid = new Grid
+            {
+                ColumnDefinitions = columnDefinitions
+            };
+
+            return grid;
+        }
+
+        private Control AddSizer(Grid grid, int column, double size = 30)
+        {
+            var ctrl = new Control { MinWidth = size, MinHeight = size };
+            ctrl.SetValue(Grid.ColumnProperty, column);
+            grid.Children.Add(ctrl);
+            return ctrl;
+        }
     }
-}
+}