[X] Pass the parent scopes to DataContext

src/Controls/src/Build.Tasks/NodeILExtensions.cs

@@ -557,6 +557,32 @@ static IEnumerable<Instruction> PushTargetProperty(ILContext context, FieldRefer
 			yield break;
 		}
 
+		static IEnumerable<Instruction> PushNamescopes(INode node, ILContext context, ModuleDefinition module)
+		{
+			var scopes = new List<VariableDefinition>();
+			do
+			{
+
+				if (context.Scopes.TryGetValue(node, out var scope))
+					scopes.Add(scope.Item1);
+				node = node.Parent;
+			} while (node != null);
+
+
+			yield return Instruction.Create(OpCodes.Ldc_I4, scopes.Count);
+			yield return Instruction.Create(OpCodes.Newarr, module.ImportReference(context.Cache, ("Microsoft.Maui.Controls", "Microsoft.Maui.Controls.Internals", "NameScope")));
+
+			var i = 0;
+			foreach (var scope in scopes)
+			{
+				yield return Instruction.Create(OpCodes.Dup);
+				yield return Instruction.Create(OpCodes.Ldc_I4, i);
+				yield return Instruction.Create(OpCodes.Ldloc, scope);
+				yield return Instruction.Create(OpCodes.Stelem_Ref);
+				i++;
+			}
+		}
+
 		public static IEnumerable<Instruction> PushServiceProvider(this INode node, ILContext context, FieldReference bpRef = null, PropertyReference propertyRef = null, TypeReference declaringTypeReference = null)
 		{
 			var module = context.Body.Method.Module;
@@ -589,12 +615,13 @@ public static IEnumerable<Instruction> PushServiceProvider(this INode node, ILCo
 				foreach (var instruction in PushTargetProperty(context, bpRef, propertyRef, declaringTypeReference, module))
 					yield return instruction;
 
-				if (context.Scopes.TryGetValue(node, out var scope))
-					yield return Create(Ldloc, scope.Item1);
-				else
-					yield return Create(Ldnull);
+				foreach (var instruction in PushNamescopes(node, context, module))
+					yield return instruction;
 
-				yield return Create(Newobj, module.ImportCtorReference(context.Cache, ("Microsoft.Maui.Controls.Xaml", "Microsoft.Maui.Controls.Xaml.Internals", "SimpleValueTargetProvider"), paramCount: 3));
+				yield return Create(Ldc_I4_0); //don't ask
+				yield return Create(Newobj, module.ImportCtorReference(context.Cache,
+					("Microsoft.Maui.Controls.Xaml", "Microsoft.Maui.Controls.Xaml.Internals", "SimpleValueTargetProvider"), paramCount: 4));
+
 				//store the provider so we can register it again with a different key
 				yield return Create(Dup);
 				var refProvider = new VariableDefinition(module.ImportReference(context.Cache, ("mscorlib", "System", "Object")));

src/Controls/src/Build.Tasks/SetPropertiesVisitor.cs

@@ -1595,6 +1595,33 @@ static void SetDataTemplate(IElementNode parentNode, ElementNode node, ILContext
 				Root = root,
 				XamlFilePath = parentContext.XamlFilePath,
 			};
+
+			//Instanciate nested class
+			var parentIl = parentContext.IL;
+			parentIl.Emit(OpCodes.Newobj, ctor);
+
+			//Copy the scopes over for x:Reference to work
+			//the scopes will be copied to fields of the anon type, the templateIL will copy them as VariableDef and populate context.Scopes
+			var i = 0;
+			foreach (var kvp in parentContext.Scopes)
+			{
+				//On the parentIL, copy the scope to a field
+				parentIl.Emit(OpCodes.Dup); //Duplicate the nestedclass instance
+				parentIl.Append(kvp.Value.Item1.LoadAs(parentContext.Cache, module.ImportReference(parentContext.Cache, ("Microsoft.Maui.Controls", "Microsoft.Maui.Controls.Internals", "NameScope")), module));
+				var fieldDefScope = new FieldDefinition($"_scope{i++}", FieldAttributes.Assembly, module.ImportReference(parentContext.Cache, ("Microsoft.Maui.Controls", "Microsoft.Maui.Controls.Internals", "NameScope")));
+				anonType.Fields.Add(fieldDefScope);
+				parentIl.Emit(OpCodes.Stfld, fieldDefScope);
+
+				//On the templateIL, copy the field to a var, and populate the Scopes
+				templateIl.Emit(OpCodes.Ldarg_0);
+				var varDefScope = new VariableDefinition(module.ImportReference(parentContext.Cache, ("Microsoft.Maui.Controls", "Microsoft.Maui.Controls.Internals", "NameScope")));
+				loadTemplate.Body.Variables.Add(varDefScope);
+				templateIl.Emit(OpCodes.Ldfld, fieldDefScope);
+				templateIl.Emit(OpCodes.Stloc, varDefScope);
+				templateContext.Scopes[kvp.Key] = new Tuple<VariableDefinition, IList<string>>(varDefScope, kvp.Value.Item2);
+			}
+
+			//inflate the template
 			node.Accept(new CreateObjectVisitor(templateContext), null);
 			node.Accept(new SetNamescopesAndRegisterNamesVisitor(templateContext), null);
 			node.Accept(new SetFieldVisitor(templateContext), null);
@@ -1604,9 +1631,6 @@ static void SetDataTemplate(IElementNode parentNode, ElementNode node, ILContext
 			templateIl.Append(templateContext.Variables[node].LoadAs(parentContext.Cache, module.TypeSystem.Object, module));
 			templateIl.Emit(OpCodes.Ret);
 
-			//Instanciate nested class
-			var parentIl = parentContext.IL;
-			parentIl.Emit(OpCodes.Newobj, ctor);
 
 			//Copy required local vars
 			parentIl.Emit(OpCodes.Dup); //Duplicate the nestedclass instance

src/Controls/src/Xaml/PublicAPI/net-android/PublicAPI.Unshipped.txt

@@ -1 +1,2 @@
 #nullable enable
+~Microsoft.Maui.Controls.Xaml.Internals.SimpleValueTargetProvider.SimpleValueTargetProvider(object[] objectAndParents, object targetProperty, Microsoft.Maui.Controls.Internals.INameScope[] scopes, bool notused) -> void

src/Controls/src/Xaml/PublicAPI/net-ios/PublicAPI.Unshipped.txt

@@ -1 +1,2 @@
 #nullable enable
+~Microsoft.Maui.Controls.Xaml.Internals.SimpleValueTargetProvider.SimpleValueTargetProvider(object[] objectAndParents, object targetProperty, Microsoft.Maui.Controls.Internals.INameScope[] scopes, bool notused) -> void

src/Controls/src/Xaml/PublicAPI/net-maccatalyst/PublicAPI.Unshipped.txt

@@ -1 +1,2 @@
 #nullable enable
+~Microsoft.Maui.Controls.Xaml.Internals.SimpleValueTargetProvider.SimpleValueTargetProvider(object[] objectAndParents, object targetProperty, Microsoft.Maui.Controls.Internals.INameScope[] scopes, bool notused) -> void

src/Controls/src/Xaml/PublicAPI/net-tizen/PublicAPI.Unshipped.txt

@@ -1 +1,2 @@
 #nullable enable
+~Microsoft.Maui.Controls.Xaml.Internals.SimpleValueTargetProvider.SimpleValueTargetProvider(object[] objectAndParents, object targetProperty, Microsoft.Maui.Controls.Internals.INameScope[] scopes, bool notused) -> void

src/Controls/src/Xaml/PublicAPI/net-windows/PublicAPI.Unshipped.txt

@@ -1 +1,2 @@
 #nullable enable
+~Microsoft.Maui.Controls.Xaml.Internals.SimpleValueTargetProvider.SimpleValueTargetProvider(object[] objectAndParents, object targetProperty, Microsoft.Maui.Controls.Internals.INameScope[] scopes, bool notused) -> void

src/Controls/src/Xaml/PublicAPI/net/PublicAPI.Unshipped.txt

@@ -1 +1,2 @@
 #nullable enable
+~Microsoft.Maui.Controls.Xaml.Internals.SimpleValueTargetProvider.SimpleValueTargetProvider(object[] objectAndParents, object targetProperty, Microsoft.Maui.Controls.Internals.INameScope[] scopes, bool notused) -> void

src/Controls/src/Xaml/PublicAPI/netstandard/PublicAPI.Unshipped.txt

@@ -1 +1,2 @@
 #nullable enable
+~Microsoft.Maui.Controls.Xaml.Internals.SimpleValueTargetProvider.SimpleValueTargetProvider(object[] objectAndParents, object targetProperty, Microsoft.Maui.Controls.Internals.INameScope[] scopes, bool notused) -> void

src/Controls/src/Xaml/XamlServiceProvider.cs

@@ -112,9 +112,15 @@ public class SimpleValueTargetProvider : IProvideParentValues, IProvideValueTarg
 	{
 		readonly object[] objectAndParents;
 		readonly object targetProperty;
-		readonly INameScope scope;
+		readonly INameScope[] scopes;
 
+		[Obsolete("Use the other ctor")]
 		public SimpleValueTargetProvider(object[] objectAndParents, object targetProperty, INameScope scope)
+			: this(objectAndParents, targetProperty, new INameScope[] { scope }, false)
+		{
+		}
+
+		public SimpleValueTargetProvider(object[] objectAndParents, object targetProperty, INameScope[] scopes, bool notused)
 		{
 			if (objectAndParents == null)
 				throw new ArgumentNullException(nameof(objectAndParents));
@@ -123,7 +129,7 @@ public SimpleValueTargetProvider(object[] objectAndParents, object targetPropert
 
 			this.objectAndParents = objectAndParents;
 			this.targetProperty = targetProperty;
-			this.scope = scope;
+			this.scopes = scopes;
 		}
 
 		IEnumerable<object> IProvideParentValues.ParentObjects => objectAndParents;
@@ -133,8 +139,10 @@ public SimpleValueTargetProvider(object[] objectAndParents, object targetPropert
 		public object FindByName(string name)
 		{
 			object value;
-			if ((value = scope?.FindByName(name)) != null)
-				return value;
+			if (scopes!=null)
+				foreach(var scope in scopes)
+					if ((value = scope?.FindByName(name)) != null)
+						return value;
 
 			for (var i = 0; i < objectAndParents.Length; i++)
 			{

src/Controls/tests/Xaml.UnitTests/Issues/Maui7744.xaml.cs

@@ -4,29 +4,28 @@
 using Microsoft.Maui.Devices;
 using NUnit.Framework;
 
-namespace Microsoft.Maui.Controls.Xaml.UnitTests
+namespace Microsoft.Maui.Controls.Xaml.UnitTests;
+
+public partial class Maui7744 : ContentPage
 {
-	public partial class Maui7744 : ContentPage
+	public Maui7744() => InitializeComponent();
+	public Maui7744(bool useCompiledXaml)
 	{
-		public Maui7744() => InitializeComponent();
-		public Maui7744(bool useCompiledXaml)
-		{
-			//this stub will be replaced at compile time
-		}
+		//this stub will be replaced at compile time
+	}
 
-		[TestFixture]
-		class Test
-		{
-			[SetUp] public void Setup() => AppInfo.SetCurrent(new MockAppInfo());
-			[TearDown] public void TearDown() => AppInfo.SetCurrent(null);
+	[TestFixture]
+	class Test
+	{
+		[SetUp] public void Setup() => AppInfo.SetCurrent(new MockAppInfo());
+		[TearDown] public void TearDown() => AppInfo.SetCurrent(null);
 
-			[Test]
-			public void ConvertersAreExecutedWhileApplyingSetter([Values(false, true)] bool useCompiledXaml)
-			{
-				var page = new Maui7744(useCompiledXaml);
-				Assert.That(page.border0.StrokeShape, Is.TypeOf<RoundRectangle>());
-				Assert.That(page.border1.StrokeShape, Is.TypeOf<RoundRectangle>());
-			}
+		[Test]
+		public void ConvertersAreExecutedWhileApplyingSetter([Values(false, true)] bool useCompiledXaml)
+		{
+			var page = new Maui7744(useCompiledXaml);
+			Assert.That(page.border0.StrokeShape, Is.TypeOf<RoundRectangle>());
+			Assert.That(page.border1.StrokeShape, Is.TypeOf<RoundRectangle>());
 		}
 	}
 }

src/Controls/tests/Xaml.UnitTests/Issues/Maui8149.xaml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ContentView xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
+             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+             xmlns:local="clr-namespace:Microsoft.Maui.Controls.Xaml.UnitTests"
+             x:Class="Microsoft.Maui.Controls.Xaml.UnitTests.Maui8149"
+             x:Name="Self">
+
+    <local:Maui8149View>
+        <local:Maui8149View.ItemTemplate>
+            <DataTemplate>
+                <local:Maui8149Item>
+                    <Label x:Name="label" Text="{Binding Source={x:Reference Self}}"/>
+                </local:Maui8149Item>
+            </DataTemplate>
+        </local:Maui8149View.ItemTemplate>
+    </local:Maui8149View>        
+
+</ContentView>

src/Controls/tests/Xaml.UnitTests/Issues/Maui8149.xaml.cs

@@ -0,0 +1,35 @@
+using Microsoft.Maui.ApplicationModel;
+using Microsoft.Maui.Controls.Core.UnitTests;
+using Microsoft.Maui.Controls.Shapes;
+using Microsoft.Maui.Devices;
+using NUnit.Framework;
+
+namespace Microsoft.Maui.Controls.Xaml.UnitTests;
+
+public partial class Maui8149 : ContentView
+{
+
+	public Maui8149() => InitializeComponent();
+
+	public Maui8149(bool useCompiledXaml)
+	{
+		//this stub will be replaced at compile time
+	}
+
+	[TestFixture]
+	class Test
+	{
+		[SetUp] public void Setup() => AppInfo.SetCurrent(new MockAppInfo());
+		[TearDown] public void TearDown() => AppInfo.SetCurrent(null);
+
+		[Test]
+		public void NamescopeWithXamlC([Values(false, true)] bool useCompiledXaml)
+		{
+			if (useCompiledXaml)
+				MockCompiler.Compile(typeof(Maui8149));
+
+			var page = new Maui8149(useCompiledXaml);
+			Assert.That((page.Content as Maui8149View).Text, Is.EqualTo("Microsoft.Maui.Controls.Xaml.UnitTests.Maui8149"));			
+		}
+	}
+}

src/Controls/tests/Xaml.UnitTests/Issues/Maui8149Item.xaml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ContentView xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
+             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+             xmlns:local="clr-namespace:Microsoft.Maui.Controls.Xaml.UnitTests"
+             x:Class="Microsoft.Maui.Controls.Xaml.UnitTests.Maui8149Item"
+             x:Name="Self">
+
+    <!--
+    
+    Note the 'x:Name="Self"
+    
+    In this *minimal* repro, all Content is provided by the DataTemplate
+    
+    -->
+
+</ContentView>

src/Controls/tests/Xaml.UnitTests/Issues/Maui8149Item.xaml.cs

@@ -0,0 +1,9 @@
+namespace Microsoft.Maui.Controls.Xaml.UnitTests;
+
+public partial class Maui8149Item : ContentView
+{
+	public Maui8149Item()
+	{
+		InitializeComponent();
+	}
+}

src/Controls/tests/Xaml.UnitTests/Issues/Maui8149View.xaml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ContentView xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
+             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+             xmlns:local="clr-namespace:Microsoft.Maui.Controls.Xaml.UnitTests"
+             x:Class="Microsoft.Maui.Controls.Xaml.UnitTests.Maui8149View"
+             x:Name="Self">
+
+
+
+</ContentView>

src/Controls/tests/Xaml.UnitTests/Issues/Maui8149View.xaml.cs

@@ -0,0 +1,20 @@
+namespace Microsoft.Maui.Controls.Xaml.UnitTests;
+
+public partial class Maui8149View : ContentView
+{
+	private Controls.DataTemplate _itemTemplate;
+	public string Text { get; set; }
+	public Microsoft.Maui.Controls.DataTemplate ItemTemplate {
+		get => _itemTemplate;
+		set {
+			_itemTemplate = value;
+			Content = _itemTemplate.CreateContent() as View;
+			Text = ((Content as Maui8149Item).Content as Label).Text;
+		}
+	}
+
+	public Maui8149View()
+	{
+		InitializeComponent();
+	}
+}