From 0cb6968ce4d8d00fcc10132039adf2a067335195 Mon Sep 17 00:00:00 2001
From: Siegfried Pammer <siegfriedpammer@gmail.com>
Date: Fri, 1 May 2026 18:14:23 +0200
Subject: [PATCH] Keep decompiler tab title in sync with selected tree node
 text

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

Assisted-by: Claude:claude-opus-4-7:Claude Code
---
 ILSpy.Tests/Editor/DecompilerViewTests.cs | 35 +++++++++++++++++++++++
 ILSpy/TextView/DecompilerTabPageModel.cs  | 20 +++++++++++--
 2 files changed, 53 insertions(+), 2 deletions(-)

diff --git a/ILSpy.Tests/Editor/DecompilerViewTests.cs b/ILSpy.Tests/Editor/DecompilerViewTests.cs
index a41254c11..9fbef51f8 100644
--- a/ILSpy.Tests/Editor/DecompilerViewTests.cs
+++ b/ILSpy.Tests/Editor/DecompilerViewTests.cs
@@ -23,7 +23,10 @@ using Avalonia.Headless.NUnit;
 
 using AwesomeAssertions;
 
+using ICSharpCode.ILSpy.Properties;
+
 using ILSpy.AppEnv;
+using ILSpy.Commands;
 using ILSpy.TreeNodes;
 using ILSpy.ViewModels;
 using ILSpy.Views;
@@ -185,6 +188,38 @@ public class DecompilerViewTests
 		tab.Text.Should().Contain("SupportedOSPlatformAttribute");
 	}
 
+	[AvaloniaTest]
+	public async Task Decompiler_Tab_Title_Tracks_Tree_Node_Text_When_Node_Loads_Late()
+	{
+		var window = AppComposition.Current.GetExport<MainWindow>();
+		window.Show();
+		var vm = (MainWindowViewModel)window.DataContext!;
+		await vm.AssemblyTreeModel.WaitForAssembliesAsync(minimumCount: 3);
+
+		// Open a fresh assembly via the command and immediately let the OpenCommand select it,
+		// before LoadedAssembly.Text has the rich "(version, tfm)" suffix wired up. This is the
+		// timing window where the tab title used to lock in the bare ShortName.
+		var newAsmPath = typeof(System.Net.Http.HttpClient).Assembly.Location;
+		var registry = AppComposition.Current.GetExport<MainMenuCommandRegistry>();
+		var openCommand = registry.Commands
+			.Single(c => c.Metadata.Header == nameof(Resources._Open))
+			.CreateExport().Value;
+		openCommand.Execute(newAsmPath);
+
+		await Waiters.WaitForAsync(() =>
+			vm.AssemblyTreeModel.SelectedItem is AssemblyTreeNode n
+				&& string.Equals(n.LoadedAssembly.FileName, newAsmPath, System.StringComparison.OrdinalIgnoreCase));
+
+		var node = (AssemblyTreeNode)vm.AssemblyTreeModel.SelectedItem!;
+		await node.LoadedAssembly.GetLoadResultAsync();
+		var tab = await vm.DockWorkspace.WaitForDecompiledTextAsync();
+
+		await Waiters.WaitForAsync(() => string.Equals(tab.Title, node.Text?.ToString(), System.StringComparison.Ordinal));
+		node.Text!.ToString().Should().NotBe(node.LoadedAssembly.ShortName,
+			"the rich form (with version + tfm) must be available, otherwise the test isn't exercising the late-update path");
+		tab.Title.Should().Be(node.Text!.ToString());
+	}
+
 	[AvaloniaTest]
 	public async Task Selecting_Assembly_Node_Emits_Header_And_Assembly_Attributes()
 	{
diff --git a/ILSpy/TextView/DecompilerTabPageModel.cs b/ILSpy/TextView/DecompilerTabPageModel.cs
index 44388ffca..1747652b0 100644
--- a/ILSpy/TextView/DecompilerTabPageModel.cs
+++ b/ILSpy/TextView/DecompilerTabPageModel.cs
@@ -18,6 +18,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.ComponentModel;
 using System.Threading;
 using System.Threading.Tasks;
 
@@ -120,11 +121,24 @@ namespace ILSpy.TextView
 			set {
 				if (currentNode == value)
 					return;
+				if (currentNode != null)
+					currentNode.PropertyChanged -= OnCurrentNodePropertyChanged;
 				currentNode = value;
+				if (currentNode != null)
+					currentNode.PropertyChanged += OnCurrentNodePropertyChanged;
 				_ = DecompileAsync();
 			}
 		}
 
+		void OnCurrentNodePropertyChanged(object? sender, PropertyChangedEventArgs e)
+		{
+			// Tree-node Text can change after we capture the title (e.g. AssemblyTreeNode swaps
+			// from ShortName to "ShortName (version, tfm)" once the assembly finishes loading).
+			// Re-read it whenever the node fires Text so the tab header stays in sync.
+			if (e.PropertyName == nameof(ILSpyTreeNode.Text) && sender is ILSpyTreeNode node)
+				Title = node.Text?.ToString() ?? "(unnamed)";
+		}
+
 		public DecompilerTabPageModel()
 		{
 			Title = "Empty";
@@ -145,7 +159,6 @@ namespace ILSpy.TextView
 				return;
 			}
 
-			var nodeTitle = node.Text?.ToString() ?? "(unnamed)";
 			var newSyntaxExtension = language.FileExtension;
 			IsDecompiling = true;
 
@@ -182,7 +195,10 @@ namespace ILSpy.TextView
 				var collectedLookup = output.DefinitionLookup;
 				var collectedUIElements = output.UIElements;
 				await Dispatcher.UIThread.InvokeAsync(() => {
-					Title = nodeTitle;
+					// Re-read Text now (instead of capturing it before decompile started) — for
+					// freshly-opened assemblies, Text only has the rich "(version, tfm)" form
+					// after the load completes during decompile.
+					Title = currentNode?.Text?.ToString() ?? "(unnamed)";
 					SyntaxExtension = newSyntaxExtension;
 					HighlightingModel = model;
 					Foldings = collectedFoldings;