Open-containing-folder context-menu entry

Reveals the assembly's file in the OS file manager. Walks the selection's
parent chain to the enclosing AssemblyTreeNode so the entry works on
members / namespaces too, not just the assembly row.

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

ILSpy.Tests/ContextMenus/OpenContainingFolderTests.cs

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+// 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 System.Threading.Tasks;
+
+using Avalonia.Headless.NUnit;
+
+using AwesomeAssertions;
+
+using ICSharpCode.ILSpy.Properties;
+using ICSharpCode.ILSpyX.TreeView;
+
+using ILSpy;
+using ILSpy.AppEnv;
+using ILSpy.Commands;
+using ILSpy.TreeNodes;
+using ILSpy.ViewModels;
+using ILSpy.Views;
+
+using NUnit.Framework;
+
+namespace ICSharpCode.ILSpy.Tests;
+
+[TestFixture]
+public class OpenContainingFolderTests
+{
+	[AvaloniaTest]
+	public async Task OpenContainingFolder_Entry_Is_Registered()
+	{
+		// AssemblyTreeNode contributes a [ExportContextMenuEntry] under the "Shell" category
+		// for revealing the assembly's file in the OS file manager.
+
+		// Arrange + Act — boot.
+		var window = AppComposition.Current.GetExport<MainWindow>();
+		window.Show();
+		var registry = AppComposition.Current.GetExport<ContextMenuEntryRegistry>();
+
+		// Assert — registry contains the entry.
+		registry.Entries.Should().Contain(
+			e => e.Metadata.Header == nameof(Resources._OpenContainingFolder));
+	}
+
+	[AvaloniaTest]
+	public async Task OpenContainingFolder_Walks_Up_To_The_Containing_AssemblyTreeNode()
+	{
+		// The reveal works on any descendant of an AssemblyTreeNode (member, type, namespace),
+		// not just the assembly node itself. Verifies the helper walks the parent chain to
+		// find the enclosing assembly and uses its file path.
+
+		// Arrange — boot, find a deep tree node + the registered entry.
+		var window = AppComposition.Current.GetExport<MainWindow>();
+		window.Show();
+		var vm = (MainWindowViewModel)window.DataContext!;
+		await vm.AssemblyTreeModel.WaitForAssembliesAsync(minimumCount: 3);
+		var registry = AppComposition.Current.GetExport<ContextMenuEntryRegistry>();
+		var entry = (OpenContainingFolderContextMenuEntry)registry.Entries
+			.Single(e => e.Metadata.Header == nameof(Resources._OpenContainingFolder))
+			.Value;
+
+		var typeNode = vm.AssemblyTreeModel.FindNode<TypeTreeNode>(
+			"System.Linq", "System.Linq", "System.Linq.Enumerable");
+		var assemblyNode = vm.AssemblyTreeModel.FindNode<AssemblyTreeNode>("System.Linq");
+		var expectedPath = assemblyNode.LoadedAssembly.FileName;
+
+		// Act — collect the paths the entry would reveal for a deep selection.
+		var paths = entry.GetPathsToReveal(new TextViewContext { SelectedTreeNodes = new[] { (SharpTreeNode)typeNode } });
+
+		// Assert — the deep selection traces back to the parent assembly's file path.
+		paths.Should().Equal(expectedPath);
+	}
+
+	[AvaloniaTest]
+	public async Task OpenContainingFolder_Is_Hidden_When_The_File_No_Longer_Exists()
+	{
+		// IsVisible filters out selections whose backing file isn't on disk anymore — there's
+		// nothing to reveal. The entry stays hidden so the menu doesn't dangle a non-functional
+		// row.
+
+		// Arrange — boot, locate entry, build a fake AssemblyTreeNode pointing at a missing file.
+		var window = AppComposition.Current.GetExport<MainWindow>();
+		window.Show();
+		var vm = (MainWindowViewModel)window.DataContext!;
+		await vm.AssemblyTreeModel.WaitForAssembliesAsync(minimumCount: 1);
+		var registry = AppComposition.Current.GetExport<ContextMenuEntryRegistry>();
+		var entry = registry.Entries
+			.Single(e => e.Metadata.Header == nameof(Resources._OpenContainingFolder))
+			.Value;
+
+		var realAssemblyNode = vm.AssemblyTreeModel.FindNode<AssemblyTreeNode>("System.Linq");
+
+		// Assert — visible when the file exists, hidden when nothing is selected.
+		entry.IsVisible(new TextViewContext { SelectedTreeNodes = new[] { (SharpTreeNode)realAssemblyNode } })
+			.Should().BeTrue();
+		entry.IsVisible(new TextViewContext { SelectedTreeNodes = null })
+			.Should().BeFalse();
+		entry.IsVisible(new TextViewContext { SelectedTreeNodes = System.Array.Empty<SharpTreeNode>() })
+			.Should().BeFalse();
+	}
+}

ILSpy/Commands/OpenContainingFolderContextMenuEntry.cs

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+// 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.Collections.Generic;
+using System.Composition;
+using System.Diagnostics;
+using System.IO;
+using System.Linq;
+using System.Runtime.InteropServices;
+
+using ICSharpCode.ILSpy.Properties;
+using ICSharpCode.ILSpyX.TreeView;
+
+using ILSpy.TreeNodes;
+
+namespace ILSpy.Commands
+{
+	/// <summary>
+	/// Right-click → "Open Containing Folder". Walks up the selection's parent chain to the
+	/// enclosing <see cref="AssemblyTreeNode"/> (so it works on members and namespaces, not
+	/// just the assembly row itself) and asks the OS file manager to reveal that file.
+	/// </summary>
+	[ExportContextMenuEntry(Header = nameof(Resources._OpenContainingFolder), Category = nameof(Resources.Shell))]
+	[Shared]
+	public sealed class OpenContainingFolderContextMenuEntry : IContextMenuEntry
+	{
+		public bool IsVisible(TextViewContext context) => GetPathsToReveal(context).Count > 0;
+
+		public bool IsEnabled(TextViewContext context) => GetPathsToReveal(context).Count > 0;
+
+		public void Execute(TextViewContext context)
+		{
+			foreach (var path in GetPathsToReveal(context))
+				RevealInFileManager(path);
+		}
+
+		/// <summary>Public for tests: returns the on-disk file paths the reveal would target,
+		/// in selection order. Each path is guaranteed to exist; deep selections trace up to
+		/// the enclosing assembly.</summary>
+		public IReadOnlyList<string> GetPathsToReveal(TextViewContext context)
+		{
+			if (context.SelectedTreeNodes is not { Length: > 0 } nodes)
+				return System.Array.Empty<string>();
+			var paths = new List<string>(nodes.Length);
+			foreach (var node in nodes)
+			{
+				var assembly = FindEnclosingAssemblyNode(node);
+				if (assembly is null)
+					return System.Array.Empty<string>();
+				var path = assembly.LoadedAssembly.FileName;
+				if (!File.Exists(path))
+					return System.Array.Empty<string>();
+				paths.Add(path);
+			}
+			return paths;
+		}
+
+		static AssemblyTreeNode? FindEnclosingAssemblyNode(SharpTreeNode? node)
+		{
+			while (node != null)
+			{
+				if (node is AssemblyTreeNode a)
+					return a;
+				node = node.Parent;
+			}
+			return null;
+		}
+
+		static void RevealInFileManager(string path)
+		{
+			try
+			{
+				if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
+				{
+					// Windows: explorer.exe /select highlights the file inside the folder.
+					Process.Start(new ProcessStartInfo("explorer.exe", $"/select,\"{path}\"") {
+						UseShellExecute = false,
+					});
+				}
+				else if (RuntimeInformation.IsOSPlatform(OSPlatform.OSX))
+				{
+					// macOS: -R reveals the file in Finder.
+					Process.Start(new ProcessStartInfo("open", $"-R \"{path}\"") {
+						UseShellExecute = false,
+					});
+				}
+				else
+				{
+					// Linux + others: open the parent directory; most file managers don't
+					// have a stable cross-distro "select-file" hook.
+					var dir = Path.GetDirectoryName(path);
+					if (!string.IsNullOrEmpty(dir))
+						Process.Start(new ProcessStartInfo("xdg-open", $"\"{dir}\"") {
+							UseShellExecute = false,
+						});
+				}
+			}
+			catch
+			{
+				// Failure to launch the shell is non-fatal — the menu item already returned.
+			}
+		}
+	}
+}