GAC browser rebuilt as a five-column sortable grid

WPF's Open-from-GAC dialog uses a ListView with five SortableGridViewColumns
(Reference Name / Version / Culture / Public Key Token / Location), each
click-to-sort, with the initial sort by name ascending. The Avalonia port
had reduced this to a one-column ListBox showing the raw ToString() —
all field-level information mashed into a single TextBlock, no per-field
sort, no Location column, no localised strings.

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

ILSpy.Tests/Views/OpenFromGacDialogStructureTests.cs

@@ -0,0 +1,82 @@
+// Copyright (c) 2026 AlphaSierraPapa for the SharpDevelop Team
+//
+// 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.Linq;
+
+using Avalonia.Controls;
+using Avalonia.Headless.NUnit;
+using Avalonia.VisualTree;
+
+using AwesomeAssertions;
+
+using ICSharpCode.ILSpy.Properties;
+
+using ILSpy.Views;
+
+using NUnit.Framework;
+
+namespace ICSharpCode.ILSpy.Tests.Views;
+
+/// <summary>
+/// Pins the GAC browser's grid shape against the WPF dialog. WPF uses a ListView with a
+/// GridView of five SortableGridViewColumns — Reference Name, Version, Culture,
+/// Public Key Token, Location — each click-to-sort. The Avalonia port started with a
+/// single-column ListBox that mashed every field into one TextBlock via
+/// <see cref="object.ToString"/>; this fixture asserts the rebuilt dialog matches the
+/// WPF column set so a future "let's go back to a simple list" doesn't quietly remove
+/// the per-field sort and column widths users came to rely on.
+/// </summary>
+[TestFixture]
+public class OpenFromGacDialogStructureTests
+{
+	[AvaloniaTest]
+	public void Dialog_Window_Title_Comes_From_Localised_Resources()
+	{
+		var dialog = new OpenFromGacDialog();
+		dialog.Title.Should().Be(Resources.OpenFrom,
+			"the dialog title must match WPF's localised Resources.OpenFrom (currently 'Open From GAC')");
+	}
+
+	[AvaloniaTest]
+	public void Dialog_Uses_A_DataGrid_With_Five_Sortable_Columns_Matching_WPF()
+	{
+		var dialog = new OpenFromGacDialog();
+		// Force layout so the DataGrid's internal column templates are realised.
+		dialog.Measure(global::Avalonia.Size.Infinity);
+		dialog.Arrange(new global::Avalonia.Rect(dialog.DesiredSize));
+
+		var grid = dialog.GetVisualDescendants().OfType<DataGrid>().FirstOrDefault();
+		grid.Should().NotBeNull(
+			"the GAC browser must use a DataGrid (not a ListBox) so each field gets its own "
+			+ "sortable column — that's the whole reason WPF picked ListView+GridView");
+
+		var headers = grid!.Columns.Select(c => c.Header as string).ToList();
+		headers.Should().Contain(new[] {
+			Resources.ReferenceName,
+			Resources.Version,
+			Resources.CultureLabel,
+			Resources.PublicToken,
+			Resources.Location,
+		}, "the five WPF column headers must all be present and localised");
+
+		grid.Columns.Should().HaveCount(5,
+			"exactly five columns — no extras, no missing fields");
+		grid.Columns.Should().AllSatisfy(c => c.CanUserSort.Should().BeTrue(
+			"every column must be sortable to match WPF's SortableGridViewColumn.SortMode=Automatic"));
+	}
+}

ILSpy/Views/GacEntry.cs

@@ -0,0 +1,71 @@
+// Copyright (c) 2026 AlphaSierraPapa for the SharpDevelop Team
+//
+// 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.Text;
+
+using ICSharpCode.Decompiler.Metadata;
+
+namespace ILSpy.Views
+{
+	/// <summary>
+	/// One row in the GAC browser. Wraps an <see cref="AssemblyNameReference"/> + the
+	/// resolved on-disk path, exposing each WPF column's bound property (ShortName,
+	/// Version, Culture, PublicKeyToken, FileName) so the DataGrid can sort by any of
+	/// them independently. <see cref="FullName"/> + <see cref="FormattedVersion"/> back
+	/// the filter, mirroring the WPF dialog.
+	/// </summary>
+	public sealed class GacEntry
+	{
+		readonly AssemblyNameReference reference;
+		string? formattedVersion;
+		string? publicKeyToken;
+
+		public GacEntry(AssemblyNameReference reference, string fileName)
+		{
+			this.reference = reference;
+			FileName = fileName;
+		}
+
+		public string FileName { get; }
+
+		public string FullName => reference.FullName;
+
+		public string ShortName => reference.Name;
+
+		public System.Version? Version => reference.Version;
+
+		public string FormattedVersion => formattedVersion ??= (Version?.ToString() ?? string.Empty);
+
+		public string Culture
+			=> string.IsNullOrEmpty(reference.Culture) ? "neutral" : reference.Culture!;
+
+		public string PublicKeyToken => publicKeyToken ??= FormatPublicKeyToken(reference.PublicKeyToken);
+
+		static string FormatPublicKeyToken(byte[]? token)
+		{
+			if (token == null || token.Length == 0)
+				return "null";
+			var sb = new StringBuilder(token.Length * 2);
+			foreach (var b in token)
+				sb.AppendFormat("{0:x2}", b);
+			return sb.ToString();
+		}
+
+		public override string ToString() => FullName;
+	}
+}

ILSpy/Views/OpenFromGacDialog.axaml

@@ -1,25 +1,46 @@
 <Window xmlns="https://github.com/avaloniaui"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         x:Class="ILSpy.Views.OpenFromGacDialog"
-        Width="600" Height="450" MinWidth="500" MinHeight="300"
+        Width="750" Height="350" MinWidth="200" MinHeight="150"
         WindowStartupLocation="CenterOwner"
-        Title="Open from GAC">
-	<Grid Margin="12,8" RowDefinitions="Auto,*,Auto,Auto" RowSpacing="6">
+        CanResize="True">
+	<Grid Margin="12,8" RowDefinitions="Auto,*,Auto" RowSpacing="6">
 		<Grid Grid.Row="0" ColumnDefinitions="Auto,*">
-			<TextBlock Grid.Column="0" Text="Filter:" VerticalAlignment="Center" Margin="0,0,8,0" />
+			<Label Grid.Column="0" Name="FilterLabel" Target="{Binding #FilterBox}"
+			       VerticalAlignment="Center" Margin="0,0,8,0" />
 			<TextBox Grid.Column="1" Name="FilterBox" />
 		</Grid>
-		<ListBox Grid.Row="1" Name="EntriesList" SelectionMode="Multiple">
-			<ListBox.ItemTemplate>
-				<DataTemplate>
-					<TextBlock Text="{Binding}" />
-				</DataTemplate>
-			</ListBox.ItemTemplate>
-		</ListBox>
-		<ProgressBar Grid.Row="2" Name="LoadingBar" Height="6" IsIndeterminate="True" />
-		<StackPanel Grid.Row="3" Orientation="Horizontal" HorizontalAlignment="Right" Spacing="6">
-			<Button Name="OkButton" Content="Open" IsDefault="True" IsEnabled="False" MinWidth="72" />
-			<Button Name="CancelButton" Content="Cancel" IsCancel="True" MinWidth="72" />
+		<DataGrid Grid.Row="1" Name="EntriesGrid"
+		          AutoGenerateColumns="False"
+		          CanUserResizeColumns="True"
+		          CanUserSortColumns="True"
+		          GridLinesVisibility="None"
+		          HeadersVisibility="Column"
+		          IsReadOnly="True"
+		          SelectionMode="Extended">
+			<DataGrid.Columns>
+				<DataGridTextColumn Width="300" CanUserSort="True"
+				                    x:CompileBindings="False"
+				                    Binding="{Binding ShortName}" />
+				<DataGridTextColumn Width="75" CanUserSort="True"
+				                    x:CompileBindings="False"
+				                    Binding="{Binding FormattedVersion}" />
+				<DataGridTextColumn Width="65" CanUserSort="True"
+				                    x:CompileBindings="False"
+				                    Binding="{Binding Culture}" />
+				<DataGridTextColumn Width="115" CanUserSort="True"
+				                    x:CompileBindings="False"
+				                    Binding="{Binding PublicKeyToken}" />
+				<DataGridTextColumn Width="*" CanUserSort="True"
+				                    x:CompileBindings="False"
+				                    Binding="{Binding FileName}" />
+			</DataGrid.Columns>
+		</DataGrid>
+		<ProgressBar Grid.Row="1" Name="LoadingBar" Height="6"
+		             VerticalAlignment="Bottom" Margin="0,0,0,0" />
+		<StackPanel Grid.Row="2" Orientation="Horizontal" HorizontalAlignment="Right" Spacing="6">
+			<Button Name="OkButton" IsDefault="True" IsEnabled="False" MinWidth="72" />
+			<Button Name="CancelButton" IsCancel="True" MinWidth="72" />
 		</StackPanel>
 	</Grid>
 </Window>

ILSpy/Views/OpenFromGacDialog.axaml.cs

@@ -20,6 +20,7 @@ using System;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.Linq;
+using System.Threading;
 using System.Threading.Tasks;
 
 using Avalonia.Controls;
@@ -28,55 +29,124 @@ using Avalonia.Threading;
 
 using ICSharpCode.Decompiler.Metadata;
 
+// Alias the WPF-shared Resources class — Window inherits an IResourceDictionary Resources
+// property that would otherwise shadow ICSharpCode.ILSpy.Properties.Resources, turning every
+// `Resources.X` into an IResourceDictionary indexer lookup that doesn't compile.
+using Loc = ICSharpCode.ILSpy.Properties.Resources;
+
 namespace ILSpy.Views
 {
 	/// <summary>
 	/// "Open from GAC" dialog: enumerates the Global Assembly Cache via the shared
 	/// <see cref="UniversalAssemblyResolver.EnumerateGac"/> + <see cref="UniversalAssemblyResolver.GetAssemblyInGac"/>
-	/// pair, surfaces the assemblies in a filterable list, returns the selected
-	/// absolute file paths. Windows-only — the GAC doesn't exist on Linux/macOS, and
-	/// the command's CanExecute gates on <c>OperatingSystem.IsWindows()</c>.
+	/// pair and surfaces each entry in a five-column DataGrid (Reference Name / Version /
+	/// Culture / Public Key Token / Location) — each header click-to-sort, initial sort
+	/// by name ascending. Multi-select; returns the selected absolute file paths via
+	/// <see cref="SelectedFileNames"/>. Windows-only — the GAC doesn't exist on Linux/macOS,
+	/// and the command's <c>CanExecute</c> gates on <see cref="OperatingSystem.IsWindows"/>.
 	/// </summary>
 	public partial class OpenFromGacDialog : Window
 	{
 		readonly ObservableCollection<GacEntry> allEntries = new();
 		readonly ObservableCollection<GacEntry> filteredEntries = new();
-		readonly System.Threading.CancellationTokenSource fetchCts = new();
+		readonly CancellationTokenSource fetchCts = new();
 
-		ListBox entriesList = null!;
+		DataGrid entriesGrid = null!;
 		TextBox filterBox = null!;
+		Label filterLabel = null!;
 		ProgressBar loadingBar = null!;
 		Button okButton = null!;
+		Button cancelButton = null!;
+		DataGridColumn nameColumn = null!;
 
 		public OpenFromGacDialog()
 		{
 			InitializeComponent();
-			entriesList = this.FindControl<ListBox>("EntriesList")!;
+			entriesGrid = this.FindControl<DataGrid>("EntriesGrid")!;
 			filterBox = this.FindControl<TextBox>("FilterBox")!;
+			filterLabel = this.FindControl<Label>("FilterLabel")!;
 			loadingBar = this.FindControl<ProgressBar>("LoadingBar")!;
 			okButton = this.FindControl<Button>("OkButton")!;
-			entriesList.ItemsSource = filteredEntries;
-			entriesList.SelectionChanged += (_, _) => okButton.IsEnabled = entriesList.SelectedItems!.Count > 0;
+			cancelButton = this.FindControl<Button>("CancelButton")!;
+			nameColumn = this.FindControl<DataGrid>("EntriesGrid")!.Columns[0];
+
+			Title = Loc.OpenFrom;
+			// OpenListDialog__Open and _Search carry leading "_" Win32-mnemonic markers
+			// (e.g. "_Open"). Avalonia's Label/Button use "_" for the same access-key purpose,
+			// so the strings drop in unchanged; the Label.Target binding wires Alt+S to the
+			// filter box exactly as WPF's <Label Target=...> did.
+			filterLabel.Content = Loc._Search;
+			okButton.Content = Loc.OpenListDialog__Open;
+			cancelButton.Content = Loc.Cancel;
+
+			// Column headers — set in code-behind rather than AXAML because the localised
+			// strings live in the linked WPF Resources.resx; binding `{x:Static ...}` from
+			// AXAML would need a namespace mapping per Window and is more boilerplate than
+			// just five assignments here.
+			entriesGrid.Columns[0].Header = Loc.ReferenceName;
+			entriesGrid.Columns[1].Header = Loc.Version;
+			entriesGrid.Columns[2].Header = Loc.CultureLabel;
+			entriesGrid.Columns[3].Header = Loc.PublicToken;
+			entriesGrid.Columns[4].Header = Loc.Location;
+
+			entriesGrid.ItemsSource = filteredEntries;
+			entriesGrid.SelectionChanged += (_, _) => okButton.IsEnabled = entriesGrid.SelectedItems!.Count > 0;
 			filterBox.TextChanged += (_, _) => Refilter();
 			okButton.Click += (_, _) => Close(SelectedFileNames);
-			this.FindControl<Button>("CancelButton")!.Click += (_, _) => Close(System.Array.Empty<string>());
+			cancelButton.Click += (_, _) => Close(System.Array.Empty<string>());
 			Closed += (_, _) => fetchCts.Cancel();
+
+			// Initial sort: name ascending — matches WPF's
+			// SortableGridViewColumn.SetCurrentSortColumn(listView, nameColumn) +
+			// SetSortDirection(Ascending). Avalonia's DataGridColumn.Sort(direction) takes
+			// System.ComponentModel.ListSortDirection; the call mutates the underlying view
+			// and updates the header glyph.
+			Opened += (_, _) => nameColumn.Sort(System.ComponentModel.ListSortDirection.Ascending);
+
+			// Auto-focus the filter so typing starts narrowing immediately — WPF achieves the
+			// same via FocusManager.FocusedElement on the Window.
+			Opened += (_, _) => filterBox.Focus();
+
 			_ = FetchAsync();
 		}
 
 		void InitializeComponent() => AvaloniaXamlLoader.Load(this);
 
 		public string[] SelectedFileNames
-			=> entriesList.SelectedItems!.OfType<GacEntry>().Select(e => e.FileName).ToArray();
+			=> entriesGrid.SelectedItems!.OfType<GacEntry>().Select(e => e.FileName).ToArray();
 
 		async Task FetchAsync()
 		{
 			var token = fetchCts.Token;
 			var seen = new HashSet<string>();
+			loadingBar.IsIndeterminate = true;
 			try
 			{
-				await Task.Run(() => {
+				// Two-phase progress, like WPF: indeterminate during EnumerateGac (we don't know
+				// the count yet), then determinate while resolving each reference's on-disk path.
+				// EnumerateGac is materialised to a list off-thread so the count is known before
+				// the resolve pass starts.
+				var references = await Task.Run(() => {
+					var list = new List<AssemblyNameReference>();
 					foreach (var reference in UniversalAssemblyResolver.EnumerateGac())
+					{
+						if (token.IsCancellationRequested)
+							break;
+						list.Add(reference);
+					}
+					return list;
+				}, token);
+
+				if (token.IsCancellationRequested)
+					return;
+
+				loadingBar.IsIndeterminate = false;
+				loadingBar.Minimum = 0;
+				loadingBar.Maximum = references.Count;
+				loadingBar.Value = 0;
+
+				await Task.Run(() => {
+					foreach (var reference in references)
 					{
 						if (token.IsCancellationRequested)
 							return;
@@ -86,7 +156,10 @@ namespace ILSpy.Views
 						if (path == null)
 							continue;
 						var entry = new GacEntry(reference, path);
-						Dispatcher.UIThread.Post(() => AddEntry(entry));
+						Dispatcher.UIThread.Post(() => {
+							AddEntry(entry);
+							loadingBar.Value++;
+						});
 					}
 				}, token);
 			}
@@ -119,31 +192,18 @@ namespace ILSpy.Views
 			var text = filterBox.Text?.Trim();
 			if (string.IsNullOrEmpty(text))
 				return true;
-			var label = entry.ToString();
-			foreach (var token in text.Split(' ', System.StringSplitOptions.RemoveEmptyEntries))
+			// Match every space-separated token against the full assembly name OR the version
+			// string — mirrors WPF's filter (FullName || FormattedVersion). All tokens must
+			// match: "system 4.0" finds entries whose FullName contains "system" AND
+			// FormattedVersion contains "4.0".
+			foreach (var token in text.Split(' ', StringSplitOptions.RemoveEmptyEntries))
 			{
-				if (label.IndexOf(token, System.StringComparison.OrdinalIgnoreCase) < 0)
+				bool inFullName = entry.FullName.IndexOf(token, StringComparison.OrdinalIgnoreCase) >= 0;
+				bool inVersion = entry.FormattedVersion.IndexOf(token, StringComparison.OrdinalIgnoreCase) >= 0;
+				if (!inFullName && !inVersion)
 					return false;
 			}
 			return true;
 		}
-
-		sealed class GacEntry(AssemblyNameReference reference, string fileName)
-		{
-			public string FileName { get; } = fileName;
-			public override string ToString()
-				=> $"{reference.Name}, Version={reference.Version}, Culture={(reference.Culture is { Length: > 0 } c ? c : "neutral")}, PublicKeyToken={FormatPublicKey(reference)}";
-
-			static string FormatPublicKey(AssemblyNameReference reference)
-			{
-				var token = reference.PublicKeyToken;
-				if (token == null || token.Length == 0)
-					return "null";
-				var sb = new System.Text.StringBuilder(token.Length * 2);
-				foreach (var b in token)
-					sb.AppendFormat("{0:x2}", b);
-				return sb.ToString();
-			}
-		}
 	}
 }