Consolidate OS shell launches into ShellHelper

The explorer.exe / open / xdg-open switch for opening a folder, revealing
a file, or opening a file with its default app was copied across eight
commands (export, save, PDB, diagram, package extraction, CFG diagram).
Replace those copies with one ShellHelper exposing OpenFolder, RevealFile
and OpenWithDefaultApplication, and route every site through it.

Assisted-by: Claude:claude-opus-4-8:Claude Code

ILSpy/Commands/CreateDiagramContextMenuEntry.cs

@@ -30,6 +30,7 @@ using ICSharpCode.ILSpyX.TreeView;
 using ILSpy.Docking;
 using ILSpy.TextView;
 using ILSpy.TreeNodes;
+using ILSpy.Util;
 
 namespace ILSpy.Commands
 {
@@ -98,35 +99,10 @@ namespace ILSpy.Commands
 			output.WriteLine();
 			output.WriteLine();
 			var diagramHtml = Path.Combine(outputFolder, "index.html");
-			output.AddButton(null, Resources.OpenExplorer, (_, _) => OpenInShell(diagramHtml));
+			output.AddButton(null, Resources.OpenExplorer, (_, _) => ShellHelper.RevealFile(diagramHtml));
 			output.WriteLine();
 			return output;
 		}
 
-		static void OpenInShell(string path)
-		{
-			try
-			{
-				if (OperatingSystem.IsWindows())
-				{
-					Process.Start(new ProcessStartInfo("explorer.exe", $"/select,\"{path}\"") { UseShellExecute = false });
-				}
-				else if (OperatingSystem.IsMacOS())
-				{
-					Process.Start(new ProcessStartInfo("open", $"-R \"{path}\"") { UseShellExecute = false });
-				}
-				else
-				{
-					// Linux: no universal "select item" command; open the parent directory instead.
-					var parent = Path.GetDirectoryName(path);
-					if (!string.IsNullOrEmpty(parent))
-						Process.Start(new ProcessStartInfo("xdg-open", parent) { UseShellExecute = false });
-				}
-			}
-			catch
-			{
-				// Best-effort: the user can navigate to the folder manually if the shell call fails.
-			}
-		}
 	}
 }

ILSpy/Commands/ExtractPackageEntryContextMenuEntry.cs

@@ -34,6 +34,7 @@ using ICSharpCode.ILSpyX.TreeView;
 using ILSpy.Docking;
 using ILSpy.TextView;
 using ILSpy.TreeNodes;
+using ILSpy.Util;
 
 using static ICSharpCode.ILSpyX.LoadedPackage;
 
@@ -133,7 +134,7 @@ namespace ILSpy.Commands
 				output.WriteLine();
 				output.WriteLine();
 				var openTarget = isFile ? path : path;
-				output.AddButton(null, Resources.OpenExplorer, (_, _) => OpenInShell(openTarget, isFile));
+				output.AddButton(null, Resources.OpenExplorer, (_, _) => { if (isFile) ShellHelper.RevealFile(openTarget); else ShellHelper.OpenFolder(openTarget); });
 				output.WriteLine();
 				return output;
 			}, token)).ConfigureAwait(true);
@@ -196,31 +197,6 @@ namespace ILSpy.Commands
 			output.WriteLine();
 		}
 
-		static void OpenInShell(string path, bool selectItem)
-		{
-			try
-			{
-				if (OperatingSystem.IsWindows())
-				{
-					var args = selectItem ? $"/select,\"{path}\"" : $"\"{path}\"";
-					Process.Start(new ProcessStartInfo("explorer.exe", args) { UseShellExecute = false });
-				}
-				else if (OperatingSystem.IsMacOS())
-				{
-					var args = selectItem ? $"-R \"{path}\"" : $"\"{path}\"";
-					Process.Start(new ProcessStartInfo("open", args) { UseShellExecute = false });
-				}
-				else
-				{
-					var target = selectItem ? Path.GetDirectoryName(path)! : path;
-					Process.Start(new ProcessStartInfo("xdg-open", target) { UseShellExecute = false });
-				}
-			}
-			catch
-			{
-				// Best-effort: user can navigate manually if the shell call fails.
-			}
-		}
 
 		static bool IsBundleItem(SharpTreeNode node)
 		{

ILSpy/Commands/OpenContainingFolderContextMenuEntry.cs

@@ -27,6 +27,7 @@ using ICSharpCode.ILSpy.Properties;
 using ICSharpCode.ILSpyX.TreeView;
 
 using ILSpy.TreeNodes;
+using ILSpy.Util;
 
 namespace ILSpy.Commands
 {
@@ -46,7 +47,7 @@ namespace ILSpy.Commands
 		public void Execute(TextViewContext context)
 		{
 			foreach (var path in GetPathsToReveal(context))
-				RevealInFileManager(path);
+				ShellHelper.RevealFile(path);
 		}
 
 		/// <summary>Public for tests: returns the on-disk file paths the reveal would target,
@@ -81,39 +82,5 @@ namespace ILSpy.Commands
 			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.
-			}
-		}
 	}
 }

ILSpy/Commands/PdbGenerator.cs

@@ -35,6 +35,7 @@ using ICSharpCode.ILSpyX.TreeView;
 using ILSpy.Docking;
 using ILSpy.TextView;
 using ILSpy.TreeNodes;
+using ILSpy.Util;
 
 namespace ILSpy.Commands
 {
@@ -135,27 +136,11 @@ namespace ILSpy.Commands
 				output.Write(string.Format(Resources.GenerationCompleteInSeconds, totalWatch.Elapsed.TotalSeconds.ToString("F1")));
 				output.WriteLine();
 				output.WriteLine();
-				output.AddButton(null, Resources.OpenExplorer, (_, _) => OpenFolder(folder));
+				output.AddButton(null, Resources.OpenExplorer, (_, _) => ShellHelper.OpenFolder(folder));
 				output.WriteLine();
 				return output;
 			}, token)).ConfigureAwait(true);
 		}
 
-		static void OpenFolder(string path)
-		{
-			try
-			{
-				if (OperatingSystem.IsWindows())
-					Process.Start(new ProcessStartInfo("explorer.exe", $"\"{path}\"") { UseShellExecute = false });
-				else if (OperatingSystem.IsMacOS())
-					Process.Start(new ProcessStartInfo("open", $"\"{path}\"") { UseShellExecute = false });
-				else
-					Process.Start(new ProcessStartInfo("xdg-open", path) { UseShellExecute = false });
-			}
-			catch
-			{
-				// Best-effort.
-			}
-		}
 	}
 }

ILSpy/Commands/ProjectExport.cs

@@ -32,6 +32,7 @@ using ILSpy.Docking;
 using ILSpy.Languages;
 using ILSpy.TextView;
 using ILSpy.TreeNodes;
+using ILSpy.Util;
 using ILSpy.Views;
 
 namespace ILSpy.Commands
@@ -86,28 +87,12 @@ namespace ILSpy.Commands
 				if (result.Success && Directory.Exists(options.OutputDirectory))
 				{
 					o.AddButton(null, ICSharpCode.ILSpy.Properties.Resources.OpenExplorer,
-						(_, _) => OpenFolder(options.OutputDirectory));
+						(_, _) => ShellHelper.OpenFolder(options.OutputDirectory));
 					o.WriteLine();
 				}
 				return o;
 			});
 		}
 
-		static void OpenFolder(string path)
-		{
-			try
-			{
-				if (OperatingSystem.IsWindows())
-					Process.Start(new ProcessStartInfo("explorer.exe", $"\"{path}\"") { UseShellExecute = false });
-				else if (OperatingSystem.IsMacOS())
-					Process.Start(new ProcessStartInfo("open", $"\"{path}\"") { UseShellExecute = false });
-				else
-					Process.Start(new ProcessStartInfo("xdg-open", path) { UseShellExecute = false });
-			}
-			catch
-			{
-				// Best-effort.
-			}
-		}
 	}
 }

ILSpy/Commands/SaveCodeHelper.cs

@@ -29,6 +29,7 @@ using ILSpy.Docking;
 using ILSpy.Languages;
 using ILSpy.TextView;
 using ILSpy.TreeNodes;
+using ILSpy.Util;
 
 namespace ILSpy.Commands
 {
@@ -80,7 +81,7 @@ namespace ILSpy.Commands
 					o.WriteLine();
 					if (Path.GetDirectoryName(path) is { Length: > 0 } directory)
 					{
-						o.AddButton(null, Resources.OpenExplorer, (_, _) => OpenFolder(directory));
+						o.AddButton(null, Resources.OpenExplorer, (_, _) => ShellHelper.OpenFolder(directory));
 						o.WriteLine();
 					}
 					return o;
@@ -139,21 +140,5 @@ namespace ILSpy.Commands
 			return string.IsNullOrEmpty(clean) ? "output" : clean;
 		}
 
-		static void OpenFolder(string path)
-		{
-			try
-			{
-				if (OperatingSystem.IsWindows())
-					Process.Start(new ProcessStartInfo("explorer.exe", $"\"{path}\"") { UseShellExecute = false });
-				else if (OperatingSystem.IsMacOS())
-					Process.Start(new ProcessStartInfo("open", $"\"{path}\"") { UseShellExecute = false });
-				else
-					Process.Start(new ProcessStartInfo("xdg-open", path) { UseShellExecute = false });
-			}
-			catch
-			{
-				// Best-effort.
-			}
-		}
 	}
 }

ILSpy/Commands/SolutionExport.cs

@@ -31,6 +31,7 @@ using ILSpy.Docking;
 using ILSpy.Languages;
 using ILSpy.TextView;
 using ILSpy.TreeNodes;
+using ILSpy.Util;
 
 namespace ILSpy.Commands
 {
@@ -81,28 +82,12 @@ namespace ILSpy.Commands
 				o.WriteLine();
 				if (result.Success && Path.GetDirectoryName(path) is { Length: > 0 } directory)
 				{
-					o.AddButton(null, Resources.OpenExplorer, (_, _) => OpenFolder(directory));
+					o.AddButton(null, Resources.OpenExplorer, (_, _) => ShellHelper.OpenFolder(directory));
 					o.WriteLine();
 				}
 				return o;
 			}).ConfigureAwait(true);
 		}
 
-		static void OpenFolder(string path)
-		{
-			try
-			{
-				if (OperatingSystem.IsWindows())
-					Process.Start(new ProcessStartInfo("explorer.exe", $"\"{path}\"") { UseShellExecute = false });
-				else if (OperatingSystem.IsMacOS())
-					Process.Start(new ProcessStartInfo("open", $"\"{path}\"") { UseShellExecute = false });
-				else
-					Process.Start(new ProcessStartInfo("xdg-open", path) { UseShellExecute = false });
-			}
-			catch
-			{
-				// Best-effort.
-			}
-		}
 	}
 }

ILSpy/Util/GraphVizGraph.cs

@@ -66,20 +66,9 @@ namespace ILSpy.Util
 			Process.Start("dot", $"\"{fileName}.gv\" -Tpng -o \"{fileName}.png\"")?.WaitForExit();
 			// Cross-platform "open file with default app": Process.Start with
 			// UseShellExecute=true works on Windows and Mac; on Linux fall back to xdg-open.
-			OpenWithDefaultApplication(fileName + ".png");
+			ShellHelper.OpenWithDefaultApplication(fileName + ".png");
 		}
 
-		static void OpenWithDefaultApplication(string path)
-		{
-			if (OperatingSystem.IsWindows() || OperatingSystem.IsMacOS())
-			{
-				Process.Start(new ProcessStartInfo(path) { UseShellExecute = true });
-			}
-			else
-			{
-				Process.Start(new ProcessStartInfo("xdg-open", path) { UseShellExecute = false });
-			}
-		}
 
 		static string Escape(string text)
 		{

ILSpy/Util/ShellHelper.cs

@@ -0,0 +1,90 @@
+// 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;
+using System.Diagnostics;
+using System.IO;
+
+namespace ILSpy.Util
+{
+	/// <summary>
+	/// Cross-platform helpers for handing a path to the OS shell: open a folder, reveal a file in
+	/// the file manager, or open a file with its default application. All calls are best-effort --
+	/// a failed launch is swallowed, since the user can navigate manually and the gesture has
+	/// already returned. Consolidates the explorer.exe / open / xdg-open switch that was copied
+	/// across the export, save, PDB, diagram and package-extraction commands.
+	/// </summary>
+	public static class ShellHelper
+	{
+		/// <summary>Opens <paramref name="path"/> (a directory) in the OS file manager.</summary>
+		public static void OpenFolder(string path) => Launch(path, selectItem: false);
+
+		/// <summary>
+		/// Reveals <paramref name="path"/> (a file) in the OS file manager, selecting it where the
+		/// platform supports it (Windows <c>/select,</c>, macOS <c>-R</c>). On Linux there is no
+		/// stable cross-distro "select file" hook, so the parent directory is opened instead.
+		/// </summary>
+		public static void RevealFile(string path) => Launch(path, selectItem: true);
+
+		/// <summary>Opens <paramref name="path"/> with its default application (image viewer,
+		/// browser, ...).</summary>
+		public static void OpenWithDefaultApplication(string path)
+		{
+			try
+			{
+				// UseShellExecute resolves the default app on Windows and macOS; Linux needs xdg-open.
+				if (OperatingSystem.IsWindows() || OperatingSystem.IsMacOS())
+					Process.Start(new ProcessStartInfo(path) { UseShellExecute = true });
+				else
+					Process.Start(new ProcessStartInfo("xdg-open", path) { UseShellExecute = false });
+			}
+			catch
+			{
+				// Best-effort: the user can open the file manually if the shell call fails.
+			}
+		}
+
+		static void Launch(string path, bool selectItem)
+		{
+			try
+			{
+				if (OperatingSystem.IsWindows())
+				{
+					var args = selectItem ? $"/select,\"{path}\"" : $"\"{path}\"";
+					Process.Start(new ProcessStartInfo("explorer.exe", args) { UseShellExecute = false });
+				}
+				else if (OperatingSystem.IsMacOS())
+				{
+					var args = selectItem ? $"-R \"{path}\"" : $"\"{path}\"";
+					Process.Start(new ProcessStartInfo("open", args) { UseShellExecute = false });
+				}
+				else
+				{
+					// Linux + others: no universal "select item" command, so revealing a file opens
+					// its parent directory.
+					var target = selectItem ? (Path.GetDirectoryName(path) ?? path) : path;
+					Process.Start(new ProcessStartInfo("xdg-open", target) { UseShellExecute = false });
+				}
+			}
+			catch
+			{
+				// Best-effort: the user can navigate manually if the shell call fails.
+			}
+		}
+	}
+}