AssemblyReferenceTreeNode.ActivateItem selects the assembly

Assisted-by: Claude:claude-opus-4-7:Claude Code

Assisted-by: Claude:claude-opus-4-7:Claude Code

ILSpy.Tests/MainWindow/MainWindowTests.cs

@@ -137,6 +137,36 @@ public class MainWindowTests
 		refFolder.Children.Should().AllBeAssignableTo<AssemblyReferenceTreeNode>();
 	}
 
+	[AvaloniaTest]
+	public async Task Activating_Assembly_Reference_Selects_Resolved_Assembly_Node()
+	{
+		var window = AppComposition.Current.GetExport<MainWindow>();
+		window.Show();
+		var vm = (MainWindowViewModel)window.DataContext!;
+		await vm.AssemblyTreeModel.WaitForAssembliesAsync(minimumCount: 3);
+
+		var assemblyNode = vm.AssemblyTreeModel.FindNode<AssemblyTreeNode>("System.Linq");
+		assemblyNode.EnsureLazyChildren();
+		var refFolder = assemblyNode.Children.OfType<ReferenceFolderTreeNode>().Single();
+		refFolder.EnsureLazyChildren();
+
+		var refNode = refFolder.Children.OfType<AssemblyReferenceTreeNode>()
+			.Single(n => n.AssemblyReference.Name == "System.Runtime");
+
+		var args = new StubRoutedEventArgs();
+		refNode.ActivateItem(args);
+
+		args.Handled.Should().BeTrue();
+		await Waiters.WaitForAsync(() =>
+			vm.AssemblyTreeModel.SelectedItem is AssemblyTreeNode selected
+				&& selected.LoadedAssembly.ShortName == "System.Runtime");
+	}
+
+	sealed class StubRoutedEventArgs : ICSharpCode.ILSpyX.TreeView.PlatformAbstractions.IPlatformRoutedEventArgs
+	{
+		public bool Handled { get; set; }
+	}
+
 	[AvaloniaTest]
 	public async Task Selecting_References_Folder_Decompiles_References_Listing()
 	{

ILSpy/TreeNodes/AssemblyListTreeNode.cs

@@ -20,6 +20,7 @@ using System;
 using System.Collections.Specialized;
 using System.Linq;
 
+using ICSharpCode.Decompiler.Metadata;
 using ICSharpCode.ILSpyX;
 
 namespace ILSpy.TreeNodes
@@ -58,5 +59,8 @@ namespace ILSpy.TreeNodes
 
 		public AssemblyTreeNode? FindAssemblyNode(LoadedAssembly asm)
 			=> Children.OfType<AssemblyTreeNode>().FirstOrDefault(n => n.LoadedAssembly == asm);
+
+		public AssemblyTreeNode? FindAssemblyNode(MetadataFile? module)
+			=> module == null ? null : FindAssemblyNode(module.GetLoadedAssembly());
 	}
 }

ILSpy/TreeNodes/AssemblyReferenceTreeNode.cs

@@ -23,7 +23,10 @@ using AvaloniaEdit.Highlighting;
 using ICSharpCode.Decompiler;
 using ICSharpCode.Decompiler.IL;
 using ICSharpCode.Decompiler.Metadata;
+using ICSharpCode.ILSpyX.TreeView.PlatformAbstractions;
 
+using ILSpy.AppEnv;
+using ILSpy.AssemblyTree;
 using ILSpy.Languages;
 using ILSpy.TextView;
 
@@ -51,6 +54,21 @@ namespace ILSpy.TreeNodes
 
 		public override object Icon => Images.Images.Assembly;
 
+		public override void ActivateItem(IPlatformRoutedEventArgs e)
+		{
+			if (parentAssembly.Parent is not AssemblyListTreeNode listNode)
+				return;
+			var resolver = parentAssembly.LoadedAssembly.GetAssemblyResolver();
+			var resolved = resolver.Resolve(reference);
+			if (resolved == null)
+				return;
+			var loaded = listNode.FindAssemblyNode(resolved);
+			if (loaded == null)
+				return;
+			AppComposition.Current.GetExport<AssemblyTreeModel>().SelectedItem = loaded;
+			e.Handled = true;
+		}
+
 		public override void Decompile(Language language, ITextOutput output, DecompilationOptions options)
 		{
 			var loaded = parentAssembly.LoadedAssembly.LoadedAssemblyReferencesInfo.TryGetInfo(reference.FullName, out var info);