Fix startup binding errors and background load sweep failure

ILSpy.Tests/AssemblyTree/BackgroundLoadSweepTests.cs

@@ -0,0 +1,102 @@
+// Copyright (c) 2026 Christoph Wille
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy of this
+// software and associated documentation files (the "Software"), to deal in the Software
+// without restriction, including without limitation the rights to use, copy, modify, merge,
+// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
+// to whom the Software is furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all copies or
+// substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
+// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
+// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+
+using System;
+using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
+
+using Avalonia.Headless.NUnit;
+using Avalonia.Threading;
+
+using ICSharpCode.ILSpy.AppEnv;
+
+using NUnit.Framework;
+
+namespace ICSharpCode.ILSpy.Tests.AssemblyTree;
+
+/// <summary>
+/// The background sweep that loads every assembly of the shown list ends by asking the commands
+/// to re-evaluate, which is what enables "Remove assemblies with load errors". That has to happen
+/// when one of the assemblies fails to load, since that is the only case the command is for.
+/// </summary>
+[TestFixture]
+public class BackgroundLoadSweepTests
+{
+	/// <summary>
+	/// Holds a load open until the test lets go of it, then ends without a single byte, which
+	/// no loader accepts. The test thereby chooses the moment the assembly fails to load.
+	/// </summary>
+	sealed class GatedEmptyStream : Stream
+	{
+		public ManualResetEventSlim Gate { get; } = new();
+
+		public override bool CanRead => true;
+		public override bool CanSeek => false;
+		public override bool CanWrite => false;
+		public override long Length => throw new NotSupportedException();
+		public override long Position { get => throw new NotSupportedException(); set => throw new NotSupportedException(); }
+
+		public override int Read(byte[] buffer, int offset, int count)
+		{
+			Gate.Wait();
+			return 0;
+		}
+
+		public override void Flush() { }
+		public override long Seek(long offset, SeekOrigin origin) => throw new NotSupportedException();
+		public override void SetLength(long value) => throw new NotSupportedException();
+		public override void Write(byte[] buffer, int offset, int count) => throw new NotSupportedException();
+	}
+
+	[AvaloniaTest]
+	public async Task Sweep_Requeries_Commands_When_An_Assembly_Fails_To_Load()
+	{
+		var (_, vm) = await TestHarness.BootAsync();
+		await Waiters.WaitForIdleAsync();
+
+		// Show a list whose only assembly cannot finish loading before the gate opens, and let
+		// everything the switch itself queues run first, so that a requery seen afterwards can
+		// only be the one that ends the sweep.
+		var stream = new GatedEmptyStream();
+		var listManager = AppComposition.Current.GetExport<SettingsService>().AssemblyListManager;
+		var list = listManager.CreateList("gated-list");
+		var assembly = list.OpenAssembly(Path.Combine(Path.GetTempPath(), "ILSpyGated.dll"), stream);
+		vm.AssemblyTreeModel.ShowAssemblyList(list);
+		await Waiters.WaitForAsync(
+			() => !Dispatcher.UIThread.HasJobsWithPriority(DispatcherPriority.Background),
+			description: "the list switch to settle");
+
+		bool requeried = false;
+		EventHandler onRequery = (_, _) => requeried = true;
+		ICSharpCode.ILSpy.Commands.CommandManager.AddRequerySuggested(onRequery);
+		try
+		{
+			stream.Gate.Set();
+			await Waiters.WaitForAsync(() => assembly.HasLoadError, description: "the gated assembly to fail loading");
+			await Waiters.WaitForAsync(() => requeried,
+				description: "a command requery after the assembly failed to load");
+		}
+		finally
+		{
+			stream.Gate.Set();
+			ICSharpCode.ILSpy.Commands.CommandManager.RemoveRequerySuggested(onRequery);
+		}
+	}
+}

ILSpy.Tests/Controls/SharpTreeViewTests.cs

@@ -32,6 +32,7 @@
 
 using ICSharpCode.ILSpyX.TreeView;
 
+using ICSharpCode.ILSpy.Controls;
 using ICSharpCode.ILSpy.Controls.TreeView;
 
 using NUnit.Framework;
@@ -65,6 +66,20 @@ public TestNode(string text, params TestNode[] children)
 		return (window, tree, root);
 	}
 
+	[AvaloniaTest]
+	public void ShowLines_Reaches_The_Connector_Lines_Of_Every_Row()
+	{
+		var (_, tree, _) = Host();
+		var lines = tree.GetVisualDescendants().OfType<TreeLines>().ToList();
+		lines.Should().NotBeEmpty("every realized row carries a TreeLines");
+		lines.Should().OnlyContain(l => l.GetValue(TreeLines.ShowLinesProperty), "lines are shown by default");
+
+		tree.ShowLines = false;
+
+		lines.Should().OnlyContain(l => !l.GetValue(TreeLines.ShowLinesProperty),
+			"the rows take the setting from the tree view they are in");
+	}
+
 	[AvaloniaTest]
 	public void Flattens_Visible_Nodes_And_Expand_Collapse_Updates_Row_Count()
 	{

ILSpy.Tests/MainWindow/StartupBindingErrorTests.cs

@@ -0,0 +1,75 @@
+// Copyright (c) 2026 Christoph Wille
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy of this
+// software and associated documentation files (the "Software"), to deal in the Software
+// without restriction, including without limitation the rights to use, copy, modify, merge,
+// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
+// to whom the Software is furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all copies or
+// substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
+// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
+// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+using Avalonia.Headless.NUnit;
+using Avalonia.Logging;
+
+using AwesomeAssertions;
+
+using NUnit.Framework;
+
+namespace ICSharpCode.ILSpy.Tests;
+
+/// <summary>
+/// A binding that fails while the main window comes up is logged by Avalonia and otherwise
+/// goes unnoticed: the bound property silently keeps its default. Booting the window with a
+/// capturing log sink pins that startup produces no such errors.
+/// </summary>
+[TestFixture]
+public class StartupBindingErrorTests
+{
+	sealed class BindingErrorSink(ILogSink? inner) : ILogSink
+	{
+		public List<string> Errors { get; } = new();
+
+		public bool IsEnabled(LogEventLevel level, string area)
+			=> area == LogArea.Binding || (inner?.IsEnabled(level, area) ?? false);
+
+		public void Log(LogEventLevel level, string area, object? source, string messageTemplate)
+			=> Log(level, area, source, messageTemplate, []);
+
+		public void Log(LogEventLevel level, string area, object? source, string messageTemplate, params object?[] propertyValues)
+		{
+			if (area == LogArea.Binding && level >= LogEventLevel.Warning)
+				Errors.Add($"{messageTemplate} [{string.Join(", ", propertyValues)}] ({source})");
+		}
+	}
+
+	[AvaloniaTest]
+	public async Task Booting_The_Main_Window_Logs_No_Binding_Errors()
+	{
+		var previous = Logger.Sink;
+		var sink = new BindingErrorSink(previous);
+		Logger.Sink = sink;
+		try
+		{
+			await TestHarness.BootAsync();
+			await Waiters.WaitForIdleAsync();
+		}
+		finally
+		{
+			Logger.Sink = previous;
+		}
+
+		sink.Errors.Should().BeEmpty("every binding in the startup UI must resolve against its data context");
+	}
+}

ILSpy/AssemblyTree/AssemblyTreeModel.cs

@@ -557,7 +557,7 @@ void ShowAssemblyList(string name)
 				ShowAssemblyList(list);
 		}
 
-		void ShowAssemblyList(AssemblyList list)
+		internal void ShowAssemblyList(AssemblyList list)
 		{
 			using var _ = AppEnv.AppLog.Phase("ShowAssemblyList(list)");
 			// Detach the previous list's collection-changed wiring so the MessageBus
@@ -631,6 +631,11 @@ void ScheduleBackgroundLoadSweep(AssemblyList list)
 						loadTasks.Add(Task.Run(async () => {
 							try
 							{ await assembly.GetLoadResultAsync().ConfigureAwait(false); }
+							catch (Exception)
+							{
+								// A file that cannot be loaded is an expected outcome, recorded on the
+								// LoadedAssembly itself (HasLoadError). It must not fault the sweep.
+							}
 							finally
 							{ throttle.Release(); }
 						}));

ILSpy/Controls/TreeLines.cs

@@ -22,6 +22,7 @@
 using Avalonia.Controls;
 using Avalonia.Media;
 
+using ICSharpCode.ILSpy.Controls.TreeView;
 using ICSharpCode.ILSpyX.TreeView;
 
 namespace ICSharpCode.ILSpy.Controls
@@ -48,12 +49,19 @@ public class TreeLines : Control
 		public static readonly StyledProperty<int> LevelProperty =
 			AvaloniaProperty.Register<TreeLines, int>(nameof(Level));
 
+		/// <summary>
+		/// Inherited from the hosting <see cref="SharpTreeView"/>; stays at its default (lines
+		/// shown) where there is none.
+		/// </summary>
+		public static readonly StyledProperty<bool> ShowLinesProperty =
+			SharpTreeView.ShowLinesProperty.AddOwner<TreeLines>();
+
 		static TreeLines()
 		{
 			// Classic Windows-Explorer dotted connector lines.
 			var pen = new Pen(Brushes.Gray, 1) { DashStyle = new DashStyle(new double[] { 1, 1 }, 0) };
 			Pen = pen.ToImmutable();
-			AffectsRender<TreeLines>(NodeProperty, LevelProperty);
+			AffectsRender<TreeLines>(NodeProperty, LevelProperty, ShowLinesProperty);
 			IsHitTestVisibleProperty.OverrideDefaultValue<TreeLines>(false);
 		}
 
@@ -73,7 +81,7 @@ public int Level {
 		public override void Render(DrawingContext context)
 		{
 			var node = Node;
-			if (node == null || node.IsRoot)
+			if (node == null || node.IsRoot || !GetValue(ShowLinesProperty))
 				return;
 
 			double height = Bounds.Height;

ILSpy/Controls/TreeView/SharpTreeView.axaml

@@ -94,8 +94,7 @@
 			<DataTemplate x:CompileBindings="False">
 				<Panel Background="Transparent" ToolTip.Tip="{Binding ToolTip}">
 					<!-- Classic tree connector lines, behind the content. -->
-					<ctrl:TreeLines Node="{Binding}" Level="{Binding Level}"
-					                IsVisible="{Binding ShowLines, RelativeSource={RelativeSource AncestorType=tv:SharpTreeView}}" />
+					<ctrl:TreeLines Node="{Binding}" Level="{Binding Level}" />
 					<StackPanel Orientation="Horizontal" Height="20">
 						<!-- Indent spacer = (Level - 1) * step (top level sits flush left). -->
 						<Border Width="{Binding Level, Converter={x:Static tv:TreeIndentConverter.Instance}}" />

ILSpy/Controls/TreeView/SharpTreeView.cs

@@ -56,7 +56,7 @@ public class SharpTreeView : ListBox
 			AvaloniaProperty.Register<SharpTreeView, bool>(nameof(ShowRootExpander), defaultValue: false);
 
 		public static readonly StyledProperty<bool> ShowLinesProperty =
-			AvaloniaProperty.Register<SharpTreeView, bool>(nameof(ShowLines), defaultValue: true);
+			AvaloniaProperty.Register<SharpTreeView, bool>(nameof(ShowLines), defaultValue: true, inherits: true);
 
 		TreeFlattener? flattener;
 		string searchBuffer = string.Empty;

ILSpy/Docking/ILSpyDockFactory.cs

@@ -199,6 +199,12 @@ public override void InitLayout(IDockable layout)
 			if (layout is IRootDock { Id: { Length: > 0 } rootId } root)
 				DockableLocator[rootId] = () => root;
 
+			// Dock's theme template binds against DockCapabilityOverrides.{CanDrag, CanDrop} on
+			// every dockable, the docks included. A layout restored from disk carries none, so
+			// fill them in here, where both fresh and restored layouts pass through.
+			foreach (var dockable in Flatten(layout))
+				dockable.DockCapabilityOverrides ??= new DockCapabilityOverrides();
+
 			base.InitLayout(layout);
 		}
 
@@ -527,6 +533,7 @@ public void ActivateAndFocus(IDock owner, IDockable dockable)
 				Alignment = dockAlignment,
 				VisibleDockables = CreateList(System.Array.Empty<IDockable>()),
 				DockCapabilityPolicy = new DockCapabilityPolicy(),
+				DockCapabilityOverrides = new DockCapabilityOverrides(),
 			};
 
 			switch (alignment)

ILSpy/Views/MainWindow.axaml

@@ -42,7 +42,16 @@
 		<local:MainToolBar DockPanel.Dock="Top" />
 
 		<!-- Update banner: docks under the toolbar, IsVisible-bound to the panel viewmodel. -->
-		<views:UpdatePanel DockPanel.Dock="Top" DataContext="{Binding UpdatePanel}" />
+		<!-- Hosted through a content template rather than given a DataContext binding of its own:
+		     the panel then never inherits the window's view model, against which its compiled
+		     bindings cannot resolve. -->
+		<ContentControl DockPanel.Dock="Top" Content="{Binding UpdatePanel}">
+			<ContentControl.ContentTemplate>
+				<DataTemplate x:DataType="vm:UpdatePanelViewModel">
+					<views:UpdatePanel />
+				</DataTemplate>
+			</ContentControl.ContentTemplate>
+		</ContentControl>
 
 		<!-- Status bar (hidden by default, like WPF) -->
 		<Border DockPanel.Dock="Bottom" Height="26" IsVisible="False" Name="statusBar">